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A Contingent Valuation of Hurricane Forecast
Improvement∗
Renato Molina1,2†, David Letson1, Brian McNoldy1, Pallab Mozumder3 and
Matthew Varkony1
1Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, Florida2Miami Herbert Business School, University of Miami, Coral Gables, Florida
3Department of Earth & Environment and Department of Economics, Florida International
University, Miami, Florida
April 2020
PRELIMINARY DRAFT
Abstract
Hurricanes are the costliest type of natural disaster in the United States. Although the damage
caused by landfalling hurricanes will never be eliminated, the number of fatalities and the
cost of preparing for and evacuating from affected locations can be reduced through improved
forecasts. We integrate atmospheric modeling and econometrics to elicit the public willingness
to pay for more accurate hurricane forecasts through a large-scale double bounded dichotomous
choice experiment. Focusing on areas recently hit by Hurricanes Florence and Michael, survey
participants are asked to value improvements in storm track, wind speed, and precipitation
forecast precision. Our results indicate respondents value further improvements in forecast
accuracy, and that they value wind speed accuracy the most. In a world where the intensity
and the frequency of hurricanes is expected to increase and research funds are limited, these
results can inform relevant agencies regarding the effectiveness of different private and public
adaptive actions, and the value of publicly funded hurricane research programs.
JEL Codes: D23, P14, P48, Q15, Q25, Q28
∗We would like to thank Andrea Schumacher and Frank Marks for incredible support and help withatmospheric modeling. We would also like to thank David Roth for facilitating access to data and preparingvisuals on the precipitation for Florence and Michael. Finally, we would also like to thank Gina Eosco andparticipants of the Weather Program Office’s Weather Economic Research Workshop for valuable feedback.This project was funded by the National Atmospheric and Oceanographic Administration through NOAAgrant NA15OAR4320064.
†Corresponding author: [email protected]
1 Introduction
Hurricanes are the costliest type of natural disaster in the United States (Weinkle et al.,
2018). While the damage caused by landfalling hurricanes will never be eliminated, the
number of fatalities and the cost of preparing for and evacuating from affected locations
can be reduced through improved forecasts. In this study, we propose and implement a
methodology to elicit preferences and estimate the willingness to pay for a better hurricane
forecast. Our results highlight that the demand for forecast improvements exists across the
ability to predict track, wind speed and precipitation, but it is also relatively elastic when
it comes to the actual rate of improvement.
To credibly achieve these measurements, this study builds on both atmospheric science
and the econometrics of stated preferences. More specifically, we create alternative scenarios
that relate to the decision-making process of the average user when faced with the threat
of a hurricane. We use a structural atmospheric model and the National Hurricane Center
(NHC) historical error statistics to construct plausible scenarios under different rates of im-
provement in the coming decade for track and wind speed, respectively. In addition, we also
propose a structural model of precipitation that allows us to construct alternative scenarios
for hurricane precipitation forecasts. We adapt these hypothetical improvements to standard
public dissemination products and construct alternative scenarios for two recent hurricanes.
Namely, Hurricanes Michael and Florence of 2018. We chose these different storms/regions
to help disentangle unobserved characteristics from other variables that condition survey
responses, but also because recently affected survey subjects would more likely be familiar
with NHC forecasts and how they might enter into adaptation decisions.
Based on these hypothetical improvements for Michael and Florence, we deploy a large-
scale randomized double-bounded dichotomous choice contingent valuation task to areas that
were affected by those hurricanes and derive their willingness to pay for error reduction in
track, wind speed, and precipitation. Our results cover more than 4500 responses and illus-
trate that improvements in the forecast are strictly positively valued among the population.
Moreover, these results are robust, even after controlling for multiple individual, household,
and geographical characteristics. These estimates suggest that the most valued attribute in
a forecast is the wind speed. While other attributes are also valued, the relative willingness
to pay is mostly associated with the experiences of different respondents. In addition, our
results also show that the respondents’ willingness to pay remains stable even after large
variations in the rate of improvement. In other words, the demand for forecast improvement
is relatively elastic, at least for fluctuations ±20% over the rate of improvement in prediction
error experienced over the last decade.
1
In a context where resources for improving hurricane forecast are limited, our results
provide several important insights that could help the public discussion on hurricane sci-
ence. First, despite the impressive improvement after the implementation of the Hurricane
Forecast Improvement Project (HFIP) in 2007, further improvements are still valued by the
general public (Gall et al., 2013). Nonetheless, our results also suggest that some of these
precision improvements may not be effectively differentiated by decision makers. This result
is consistent with Murphy (1993), who argues that skillful forecasts may not be valuable and
vice versa (i.e., value is not increasing monotonically in quality). The true value of a forecast
lies on its effectiveness at facilitating better adaptive behavior in the face of a hurricane, and
our results highlight the possibility that some of these technicals improvements may not be
perfectly internalized by the decision-makers -at least in the beginning.
Second, and while track and wind speed are the focus of HFIP (Gall et al., 2013), other
forecast attributes such as precipitation are also valued. These results highlight the tension
surrounding mandated improvements standards, and how future policies might be able to
balance costs and benefits of executive and legislative mandates on publicly funded research.
2 Background
2.1 The Economics of Hurricane Forecasts
Hurricanes threaten the status, sustainability and security of coastal communities more than
ever before (Gaddis et al., 2007). Accordingly, there is a growing demand for producing more
precise weather forecast information to make vulnerable communities better prepared and
resilient (Ewing et al., 2007). As the government responds to this demand, it becomes crucial
to understand how the public uses and values these actions. In particular, maintaining
and expanding the resources necessary to produce officially sanctioned hurricane forecasts
(Emanuel, 2005; Mozumder et al., 2015).
The literature has already explored this problem. Letson et al. (2007) provide a the-
oretical framework to analyze the economic value of hurricane forecasts and discussed the
research needs for producing reliable value estimates. Nonetheless, and despite the guidelines
from Letson et al. (2007), measuring the value of improved weather/hurricane forecasts can
be challenging. People may not have a well-defined preference for these products, and their
preferences may be influenced by their subjective risk perceptions. Moreover, people’s risk
averting behavior and the value they put on an accurate forecast are oftentimes intertwined.
To the best of our knowledge, only a handful of studies have previously attempted to
derive the value of either weather or hurricane forecasts. In particular, Lazo et al. (2008)
2
estimate that the general public in the USA values weather information provided by the
National Weather Service (NWS) at about $280/household/year. Their estimates can be
extrapolated to a value of more than $30 billion for the whole country, when considering all
households susceptible to hurricanes.
In addition, Lazo and Waldman (2011) conduct a stated preference study (choice exper-
iment) for valuing improved hurricane forecasts based on a small non-random sample. The
sample size was eighty (general public, above eighteen years, living within thirty miles of the
coast in the Miami - Fort Lauderdale Metropolitan Area). They estimate the willingness
to pay (WTP) for improvements in several forecast attributes, such as expected landfall
time, maximum wind speed, projected landfall location, and expected storm surge. Their
results suggest that the total WTP for forecast improvement is about $13.19 per household
per year. For an estimated population of 2.5 million in Miami-Dade County in 2009, they
extrapolate that the total value of the improved hurricane forecast would be about $11.6
million. Consequently, there were more than 73 million people living in hurricane-prone
areas in 2010, which would imply a total value of $340 million at a national scale for this
improved hurricane forecast.
Other studies have also explored this question outside the United States. One such study
is Ahsan et al. (2020), who estimate the household WTP for improved early warning services
(EWS) in coastal areas of Bangladesh. Based on a choice experiment conducted on 490
randomly selected households from Khulna, Satkhira, and Barguna districts, they estimate
household WTP for improved EWS at about $ 5.57/per year. The attributes they consider
include precise information on the landfall time of the cyclone1 with projected impacts, more
frequent radio forecasts, and voice messages via mobile phones. In another study, Nguyen
et al. (2013) conduct a similar choice experiment in Vietnam. They collect responses from
1014 Vietnamese households for the same attributes of a cyclone warning service. They
estimate a “one-time” payment WTP of $7.1-8.1/household. Similarly, Anaman et al. (1998)
estimate the WTP of Australian households in Queensland for access to cyclone warning
services, and their calculations suggest the mean annual WTP is about $45/household/year.
Noticeably, all of the aforementioned literature relies on stated preference studies. It is
only natural to question why. The answer is multifaceted, but the reasons can be traced to
the lack of reliable data on the actions of individuals as well as the lack of quasi-experimental
variation in the quality of hurricane forecast. Nonetheless, when revealed preference data
are inadequate to capture the behavioral responses to hurricane risk information and man-
agement issues, carefully-designed stated preference with granular household survey can be
1Essentially, cyclones, and typhoons are the same weather phenomenon. The only difference is wherethey take place geographically.
3
used to provide reliable estimates. More specifically, Whitehead (2005) shows that hypothet-
ical stated preferences can predict actual hurricane risk averting behaviors reasonably well,
which in turn implies that stated preference data regarding hurricanes are a valid proxy for
actual decisions on the ground.
Against this backdrop, we implement a contingent valuation survey based on a large
representative sample to understand public preferences for different attributes of improved
hurricane forecasts. In particular, we will focus on the areas affected by Hurricanes Florence
and Michael in 2018. These two prominent storms are described in the next section.
2.2 Hurricanes Florence and Michael
During the 2018 Atlantic hurricane season, Hurricane Florence and Hurricane Michael were
two significant landfalling hurricanes on the continental United States. Florence was a long-
track hurricane that formed on the west coast of Africa on the 30th of August, intensifying
to an upper-end Category 4 hurricane in the open ocean south of Bermuda, then weakening
to a Category 1 hurricane as it made landfall near Wilmington, North Carolina on the 14th
of September.2
The storm resulted in widespread flooding, which caused 52 fatalities and approximately
$24 billion in damage (Stewart and Berg, 2018). Michael, on the other hand, formed in the
western Caribbean Sea on the 6th of October, which was only four days prior to making
landfall. It tracked north into the Gulf of Mexico and it strengthened from a tropical storm
to a Category 5 hurricane in under sixty hours. It continued to strengthen up until landfall on
the 10th of October, when it reached its peak sustained wind speed of 161 mph. Michael made
landfall southeast of Panama City, Florida. The storm resulted in catastrophic damages to
structures and trees, and the Mexico Beach area was inundated by a 14-foot storm surge.
Michael was responsible for 59 fatalities and approximately $25 billion in damages (Beven
et al., 2018).
We display the estimated surface wind speed swaths and observed total rainfall accu-
mulation swaths for both storms in Figure 1. The wind swaths are generated using the
parametric model of Knaff et al. (2007) integrated along the observed track at five-minute
intervals, and a simple 10% reduction of surface wind speeds over land outside the radius
of maximum wind (Kaplan and DeMaria 1995). Storm intensity, track, and size parameters
are taken from the IBTrACS v4 database (Knapp et al., 2010). The rainfall swaths are
2As defined by the National Hurricane Center, the Saffir-Simpson Hurricane Wind Scale is a categoricalrating from 1 to 5 based on a hurricane’s peak sustained wind speed. The scale estimates potential prop-erty damage. Hurricanes reaching Category 3 and higher are considered major hurricanes because of theirpotential for significant loss of life and damage Simpson and Saffir (1974).
4
an interpolated blend of raingauge data compiled by David Roth at the NOAA Weather
Prediction Center.3
Figure 1: Wind and rain swaths for Hurricanes Florence and Michael. The esti-mated peak wind swaths are in the top two panels, shaded by Saffir-Simpson category; the observed rainfallaccumulation swaths are in the bottom two panels, shaded in inches. The wind swaths are generated usinga parametric model and uniform reduction over land.
3 Theory
This section illustrates a simple utility model that guides our empirical evaluation, and fol-
lows the approach proposed by Carson and Hanneman (2005) and Lazo and Waldman (2011).
Let u(x|f, h) be the utility function of an individual that enjoys a consumption bundle x in
the face of a hurricane with a given forecast accuracy, f , and probability of occurrence h.
A rational utility maximizing individual will choose bundle x, so as to maximize her utility
subject to her budget, y. Let v(p, y|f, h) denote the indirect utility of the individual under
price vector p. u(x|f, h) is increasing and quasi-concave in x, which implies v(p, y|f, h) is
decreasing in p and increasing in y.
3The archive can be found at: https://www.wpc.ncep.noaa.gov/tropical/rain/2018.html
5
Let f 0 and f 1 be two different forecast accuracy levels, such that f 0 < f 1.4 The dollar
value of the change in f , w, is then given by:
v(p, y|f 0, h) = v(p, y − w|f 1, h) (1)
Therefore, willingness to pay (WTP) for improving from f0 to f1 can be written as
w(f 0, f 1, p, y). Let m(p, f, u|f, h) be the expenditure function for the direct utility function
u(x|f, h). It follows that the expenditure function is increasing in u, nondecreasing, concave
and homogenous of degree 1 in p. Because we are implicitly assuming that improvements in
the forecast are desired, the expenditure function is also decreasing in f . The implication is
that m(p, f, u|f, h) > 0 for any f , and that w < y.
Depending on the structural assumptions on u(x|f, h), w(f 0, f 1, p, y) could be derived
in several different ways (Carson and Hanneman, 2005). Particularly for this study and
assuming competitive markets for the essential bundle of goods, x, we will assume that the
individual WTP w(f 0, f 1, p, y) can be represented by the following linear function:
wi(f0, f 1, p, y) = x′iβ + εi (2)
with x′i as a vector of observables at the individual level. ε is a zero-mean idiosyncratic
random component and it is additive to the difference in indirect utility. The data we use
to fit this relationship is described below.
4 Data
4.1 Constructing scenarios of hurricane forecast improvements
To construct the hypothetical scenarios, we use historical forecast errors from the National
Hurricane Center (NHC). NHC calculates and provides its annual average error statistics
of track and wind speed. These errors come from comparing the values in all of the real-
time forecasts against the corresponding observed “best-track” values.5 As of 2020, NHC
produces track and wind speed forecasts and error statistics for all tropical and subtropical
cyclones in the Atlantic and Eastern North Pacific basins out to 12, 24, 36, 48, 72, 96, and
120 hours. For this study, we use the 72-hour forecast errors from the Atlantic basin. Error
trends from the previous decade are then used to generate trends in the coming decade (i.e.,
4Note that our underlying assumption only covers the willingness to pay for a better forecast, and itexcludes the possibility of a willingness to accept for a worse forecast.
5See the historical forecast errors at https://www.nhc.noaa.gov/verification/pdfs/1990-present_
OFCL_ATL_annual_int_errors.pdf
6
2008-2018 and 2018-2028). Because we are concerned with the critical 72-hour lead time
before landfall (Regnier, 2008), we work with the forecast for Florence from 11 September
at 1200 UTC (landfall was 14 September at 1115 UTC) and the forecast for Michael from 7
October at 1800 UTC (landfall was 10 October at 1730 UTC).
For track errors, we use the “cone of uncertainty” (just “cone” hereafter) because of the
public’s familiarity with it since its introduction in 2002. The NHC updates the size of the
cone each year based on track errors over the past five hurricane seasons. It is designed to
contain the center (eye) of a storm 23
of the time, implying that historically there is a 13
chance that the storm will track outside the cone. Because of the sliding five-year averages,
variations in the size of the cone are quite smooth from year to year.
The observed and the three hypothetical trends of track forecast error are shown in panel
a) of Figure 2, with the most aggressive track forecast improvement as the maroon dashed
line, the status-quo rate of improvement as the red dashed line, and the reduced rate of
forecast improvement as the orange dashed line. The average trend of improvement over
the previous decade (2008-2018) is calculated to be 41.3%. When generating hypothetical
scenarios, we assume that the trend would be to continue that same rate of progress in
the coming decade (a status quo rate for the 2018-2028 period); this status quo is shown
by the dashed red line which reaches 67.2 miles in 2028. The other scenarios accelerate or
decelerate the rate of progress by 20%, producing decadal error reduction rates of 49.6%
or 33.0% (dashed maroon and orange lines, respectively). Accordingly, these varying rate
changes yield a 72-hour cone radius of 57.8 and 76.7 miles.
Wind speed errors are handled slightly differently. Rather than using a sequence of sliding
five-year averages, we calculate a linear trend through individual annual error values; the
2008-2018 trend line yields a 29.4% reduction in error. This improvement is shown in panel
b) of Figure 2 by the solid blue line. From the individual annual values denoted by light blue
dots, it can be seen that a substantial amount of inter-annual variability arises. Similar to
the treatment of the track forecast error improvements, we project into the coming decade
(2018-2028) at three varying rate changes; a 20% increase, a constant increase, and 20%
decrease relative to the previous decade’s improvement rate. This produces decadal error
reduction rates of 35.3%, 29.4%, or 23.5% (dashed maroon, red, or orange lines, respectively).
In 2018, the trend line has a value of 13.5 mph, then by 2028 the 72-hour wind speed errors
drop to 8.7, 9.5, or 10.3 mph, respectively.
Note that the hypothetical future errors are calculated using a percentage rather than a
static number because errors can only approach zero, not reach zero or become negative. So
the slope of the blue line and the slope of the red line are not equal by design. In addition
to reducing the future errors, we also adjust the forecast values closer to the observed values
7
Figure 2: Historical and hypothetical hurricane forecast errors. Panel a) shows thetrend in the size of the “cone of uncertainty” for 72-hour track forecasts, while panel b) shows the trend inerrors for wind speed. The same average percentage of improvement from 2008-2018 is extrapolated to 2028using the same rate of improvement (“Status Quo”, red dashed line), a 20% increase in that rate (“StatusQuo +20%”, maroon dashed line), and a 20% decrease in that rate (“Status Quo -20%”, orange dashed line).
by the same percentage. In other words, we expect that forecasts in future decades will be
more accurate and with less uncertainty surrounding them. As pointed out by Landsea and
Cangialosi (2018), forecasts have been generally improving over the past several decades, but
there will come a time when forecasts can no longer be improved due to the inherent limit
of predictability of chaotic systems such as the atmosphere. For the sake of this study, we
assume that limit will not be reached in the coming decade and that progress will continue.
While track and wind speed are fairly simple metrics to calculate and verify, rainfall
accumulation metrics are more complex. Rainfall is dependent on the hurricane track which
includes variables location and speed. In addition, rainfall accumulation depends on the
storm’s intensity and size, the topography of the affected area, and a number of other factors.
To generate rainfall swaths in an objective and uniform fashion, we use the parametric
hurricane rainfall model (PHRaM) of Lonfat et al. (2007). PHRaM accounts for storm size,
intensity, wind-shear-based storm asymmetry, and topographic effects. The model is run for
a given set of values including; latitude, longitude, intensity, wind shear magnitude, wind
shear direction, and radius of maximum wind. It can produce a full five-day forecast rainfall
swath beginning 72 hours before landfall. We utilize the hypothetical values of intensity and
location that were defined above, and use wind shear values from the operational Statistical
Hurricane Intensity Prediction Scheme (SHIPS) model output (DeMaria and Kaplan, 1994).
Finally, to address current and future uncertainty in the rainfall forecast, we use the
1000-member Monte Carlo ensemble that NHC creates every six hours for each active storm
8
to produce its suite of wind speed probability forecasts (DeMaria et al., 2009). PHRaM is
run on all 1000 realizations, which in turns allows us ask questions related to the probability
of over- or under-forecasting rainfall compared to a deterministic forecast. Further, we can
extend this analysis for all potential error reduction scenarios (Marks et al., 2020). In the
survey, using the forecast in 2018 as a benchmark, the respondents are shown a map with a
shaded region indicating the area where there was at least a 20% probability of the rainfall
amounts generated from the forecast storm attributes being less than the rainfall amounts
generated from the observed storm attributes (an under-forecast) by at least one inch. The
following section explains how we use NHC historical error data and rainfall predictions to
elicit the public’s willingness to pay for hurricane forecast improvements.
4.2 Survey implementation
To appropriately elicit the value of improved hurricane forecast, we implement atmospheric
model insights into a web based survey questionnaire. We target individuals recently affected
by our chosen hurricanes, Michael and Florence, so participants can compare the forecast
products they know with those derived from an improved forecast’s capability. Our sample is
divided between two communities: those affected by Florence and those affected by Michael.
More specifically, communities under FEMA advisories 56 and 15, respectively.6 That des-
ignation includes areas in Florida, Georgia, North and South Carolina. Respondents answer
the sequence of questions described in Figure 3, which seek to extract relevant information
on their backgrounds and attitudes towards forecast improvements.
Participants are initially screened by the zip code where they live. Following the intro-
duction, respondents are briefed on the nature of the survey. We include one more screening
question regarding the participants ability to provide thoughtful and honest answers in the
survey. The questions that follow, solicit participant information on residential living status
and the extent of insurance coverage for their homes. This set of questions asks respondents
to describe their familiarity with hurricane risk and the US governmental programs created
to protect against hurricane-related damages.
The next question set asks respondents to recount their experience with their respective
storm (i.e., Florence or Michael). These questions are preceded with a statement describing
the acceptable limits of hurricane experience, informing participants that their experience
is not only limited to physical impacts. Depending on an individual’s response to their
encounter with the most recent hurricane, a set of follow up questions is presented inquiring
6The official advisories for Florence and Michael are available at https://www.nhc.noaa.gov/archive/2018/FLORENCE_graphics.php and https://www.nhc.noaa.gov/archive/2018/MICHAEL_graphics.php,respectively
9
Figure 3: Survey Flow Chart. This schematic describes the structure of the survey. The rectan-gular sections represent questions pertaining to participant background. The middle of the diagram displaysour dichotomous choice design. A random attribute is matched with a random improvement rate. Eachattribute and each rate are only used once. The participants must vote in favor or against an annual taxbetween 1-50 dollars. The tax is then adjusted based on the previous answer, and the respondents are pre-sented with another yes/no vote. This design is repeated three times. Both hexagons represent the beginningand end of the survey. Respondents must enter their zip in both instances as a way of quality control.
about evacuation decisions and damages to property from the storm. The section concludes
with general questions about evacuation plans and the number of individuals living in the
residence.
After documenting the respondents’ experience with the past hurricane, the survey de-
scribes the role of federal agencies in providing hurricane information. We briefly explain
the process of fund allocation for hurricane research. In addition, we mention our motiva-
tion in collecting individual attitudes towards tax increases to support funding for hurricane
forecasting research. We ask respondents to rank, in order of importance, the value of hurri-
cane forecast information for their own decision making. These forecast components include
information on; hurricane track, wind speed, storm surge, and the level of anticipated rain-
fall. Given our atmospheric modeling possibilities, we focus on three of the four forecast
components for our contingent valuation study.
We provide respondents with a set of three random scenarios needed for the contingent
valuation. These three forecast components are presented in Figure 4. This figure represents
the status quo forecast improvements for each improvement scenario. Moving along columns
from left to right, these figures represent changes in decadal trends of 72-hour track forecast
accuracy, intensity forecast error, and accumulated precipitation. As shown in Figure 3,
the survey randomly generates a scenario combining one random forecast attribute with one
random rate of forecast change. The respondents are provided with a brief description of
the randomly selected forecast attribute. A visual is included in the description to demon-
10
Figure 4: Hypothetical Forecast Components. This figure presents the maps and chartsthat were presented to survey participants. The top row of panels (a,b,c) is included in the Florence surveyand the bottom row (d,e,f) is included for the Michael survey. Each of the three columns contain figuresrepresenting forecast improvements corresponding to the status quo improvement. Panels a) and d) show thetrack uncertainty defined by the size of the cone for 72-hour forecasts. Panels b) and e) are the average windspeed error, and are the same because average wind speed forecast error is the same regardless of location.Panels c) and f) are the rainfall under-forecast area.
strate the change in accuracy of the given forecast as a result of the randomly chosen rate
improvement. As stated earlier, the change in forecast abilities are related to the baseline
improvements from 2008 to 2018. The proposed improvements include a 20% increase, a
20% decrease, or a constant rate of improvement (relative to the prior decade) in forecasting
accuracy. Respondents are then asked to answer yes or no to a randomly-generated annual
tax increase meant to pay for these forecast improvements. To decrease ambiguity, we spec-
ify that the tax increase takes place at the household level and lasts for ten years. These
random tax increases follow a uniform distribution between $1 to $50.
A follow-up yes or no question with an increased or decreased tax, relative to the original
tax, is then presented to the respondent. As required in a dichotomous choice design, if the
respondent answered yes to the initial tax increase, then the following tax is 20% greater.
On the other hand, if the respondent’s initial answer is no, then the follow-up tax is reduced
by 20%. This random process combining a forecast attribute and rate of improvement is
repeated three times. Each survey participant observes all three of the forecast attributes
combined with a unique rate change.
The survey concludes with a sequence of questions asking respondents to explain their
11
own decision making process. Respondents are finally asked to identify their level of belief
that public officials will use the survey information to guide policy implementation.
5 Empirics
We seek to elicit the preferences of the respondents using a double bounded dichotomous
choice design (Hanemann et al., 1991). In our design, each respondent is presented with
a randomly selected hurricane forecast attribute and a randomly selected potential rate of
improvement. For each of these dimensions and their respective rates of improvement, each
individual i is presented with a first bid, b1i ∼ U[1, 50]. Depending on her answer, she would
be presented with a followup bid, b2i . If the answer in the first round is positive (i.e., she
accepts the tax burden on her household), the bid is then increased by 20%. If the answer
in the first round is negative, the bid is decreased by 20% instead.
For each forecast attribute, a respondent would then fall into one of four possible sce-
narios. Let Y ji ∈ {0, 1} denote the individual response for bid j = {1, 2}, and Y i = [Y 1
i , Y2i ]
the tuple representing her response to both questions for a given forecast attribute. Further,
suppose that for individual i, the willingness to pay for a certain rate of improvement is
given by:
WTPi(xi) = x′iβ + εi (3)
with xi as the vector including the order in which the forecast attribute is shown to the
respondent and the rate of improvement, along with all other individual observables. Fur-
thermore, let εi ∼ N(0, σ2). The four possible scenarios, as a function of the individual
survey responses, are then given by:
Pr(Y i = [1, 0]|xi) = Φ
(x′iβ − b1
i
σ
)− Φ
(x′iβ − b2
i
σ
)(4)
Similarly:
Pr(Y i = [1, 1]|xi) = Pr(x′iβ + εi > b1i ∧ x′iβ + εi > b2
i )
Because b2i > b1
i and Pr(xiβ + εi > b1i |xiβ + εi ≥ b2
i ) = 1, we can invoke Bayes rule, which
implies:
Pr(Y i = [1, 1]|xi) = Φ
(x′iβ − b2
i
σ
)(5)
12
The third scenario is then given by:
Pr(Y i = [0, 1]|xi) = Φ
(x′iβ − b2
i
σ
)− Φ
(x′iβ − b1
i
σ
)(6)
Accordingly, if both bids are rejected, we have the fourth scenario as:
Pr(Y i = [0, 0]|xi) = 1− Φ
(b2i − x′iβσ
)(7)
Finally, the log-likelihood function for parameters β and σ, would be then given by:
L(β, σ|xi) = 1Yi=[1,0] ln
[Φ
(x′iβ − b1
i
σ
)− Φ
(x′iβ − b2
i
σ
)]+ 1Yi=[1,1] ln
[Φ
(x′iβ − b2
i
σ
)]+ 1Yi=[0,1] ln
[Φ
(x′iβ − b2
i
σ
)− Φ
(x′iβ − b1
i
σ
)]+ 1Yi=[0,0] ln
[1− Φ
(b2i − x′iβσ
)](8)
The estimates for the parameters of interest, β and σ, maximize equation 8. Recalling from
equation 3 that E[WTPi|xi] = x′iβ, the estimate for the average willingness to pay is then
given by:
WTP = x′β (9)
with x as the vector of mean values for the order in which the forecast attribute is presented,
the rate of improvement, and all other observables for a given respondent. Our strategy is
then to perform this analysis for each individual hurricane forecast attribute (i.e., track, wind
speed and precipitation). Our main specification includes order and hypothetical rate of im-
provement, controls for income, dummy variables for female respondents as well as for having
experienced and evacuated during Florence or Michael, perceptions of how the respondents’
answers will be considered as well as to influence a policy change, and the respondent’s be-
liefs of a hurricane affecting them in the long-term. The results of implementing this model
are presented in the next section.
6 Results
In this section, we present the results of deploying the survey, econometrically analyzing
the responses, and the extrapolation benefits (willingness to pay) to susceptible populations.
In addition, we complement this section with a series of tables that are included in the
13
Appendix.
6.1 Summary statistics
Our elicitation device is a web-based survey. Following the design specified in Section 4,
the survey is distributed and collected using the Qualtrics platform. Our sample targets
two sub-populations: zip-codes affected by Hurricane Florence, and zip-codes affected by
Hurricane Michael. From here onwards, we refer to these two samples as Florence and
Michael, respectively. The summary statistics for the survey are shown in Table 1. In the
table, “Answers” are binary (0/1) and take values of 0 or 1 for negative and positive answers,
respectively.
Control Set 1 includes the average individual income per year by zip code (thousands of
2018 USD), binary indicators if the respondent self identifies as a female, if the respondent
self-identifies her household as having experienced the storm, as well as if the respondent
evacuated in the face of the storm. In addition, we include a categorical value from 1
to 5 representing the attitude respondents have that public authorities will take the survey
responses into consideration (Voice), and the attitude that survey answers will affect internal
changes in Department of Commerce (Action). Finally, this set includes a self-assessed
probability of the respondent being affected by a hurricane in the long-term (time horizon
of 10 years and range 10−4 − 1).
On the other hand, Control Set 2 includes the remaining observables of the survey with a
continuous age variable (#), a binary variable if the respondent declares herself as the owner
of their current residence, and a continuous variable for how long she may have inhabited
her current residence. In addition, we include variables for the self-assessed probability of
the respondent being affected by a hurricane in the short-term (5 years and range between
10−4−1). This set also includes a categorial value for the level of awareness of the respondent
regarding hurricane insurance, the Federal Emergency Management Agency (FEMA), and
the National Flood Insurance Program (NFIP). The level of awareness ranges from 0 to
4 representing no awareness to highly familiar, respectively (0-4). Finally, the remaining
variables include a binary indicator if the respondent declares to have suffered damages due
to the storm, and a continuous variable indicating how many individuals reside in her current
residence.
Table 1 illustrates several patterns. First, there are no statistically significant differences
between the unconditional mean for the referendum answers across samples. In other words,
without controlling for observables, the differences in answers of these two samples would
be statistically indistinguishable from zero. Nonetheless, these two groups are different in
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Table 1: Summary Statistics for Survey Responses
Florence Michael DifferenceMean Std.Dev. Mean Std.Dev. Mean Diff. Std. Error
Track
Track Answer 1 (0/1) 0.617 0.486 0.622 0.485 -0.005 0.015Track Answer 2 (0/1) 0.590 0.492 0.581 0.494 0.009 0.015
Wind Speed
Wind Speed Answer 1 (0/1) 0.565 0.496 0.571 0.495 -0.006 0.016Wind Speed Answer 2(0/1) 0.550 0.498 0.548 0.498 0.002 0.016
Precipitation
Precipitation Answer 1 (0/1) 0.562 0.496 0.549 0.498 0.012 0.016Precipitation Answer 2 (0/1) 0.537 0.499 0.543 0.498 -0.006 0.016
Control Set 1
Income ($ ×103) 68.681 19.507 61.672 19.252 7.009∗∗∗ 0.610Female (0/1) 0.697 0.460 0.752 0.432 -0.055∗∗∗ 0.014Experience (0/1) 0.817 0.387 0.911 0.284 -0.095∗∗∗ 0.011Evacuated (0/1) 0.187 0.390 0.175 0.380 0.012 0.012Voice (1− 5) 2.708 1.273 2.871 1.277 -0.163∗∗∗ 0.040Action (1− 5) 2.597 1.218 2.792 1.236 -0.195∗∗∗ 0.038Long-Term Risk (10−4 − 1) 0.203 0.349 0.141 0.287 0.062∗∗∗ 0.010
Control Set 2
Age (#) 46.129 17.582 40.258 15.998 5.871∗∗∗ 0.541Owner (0/1) 0.583 0.493 0.489 0.500 0.094∗∗∗ 0.016Household Tenure (#) 15.458 113.085 17.540 155.076 -2.082 4.020Short-Term Risk (10−4 − 1) 0.150 0.294 0.105 0.242 0.045∗∗∗ 0.009Hurricane Insurance Awareness (0− 4) 2.900 1.081 2.981 1.085 -0.080∗ 0.034FEMA Program Awareness (0− 4) 2.067 1.224 2.081 1.280 -0.014 0.039NFIP Insurance awareness (0− 4) 1.540 1.289 1.492 1.329 0.048 0.041Damage (0/1) 0.242 0.428 0.466 0.499 -0.224∗∗∗ 0.014Household Size (#) 2.873 1.880 3.343 3.302 -0.470∗∗∗ 0.076+ p < 0.10, ∗ p < 0.05, ∗∗ p < 0.01, ∗∗∗ p < 0.001
Notes: The unit of of observation is an individual respondent. The table shows the summary statistics for all of the variablesincluded in the analysis. Bids, order and rate are not included as they, by design, are uniformly distributed. The table is dividedas a function of the geographical sample, and then the differences between the two samples. The number of observations is 3,150for Florence and 1,500 for Michael. For each variable, the respective units are presented in parenthesis. Monetary variables arein 2018 dollar values. Statistical significance based on a two-sided t-test for difference in population means.
many ways: Florence has a higher income, 5% more participants that self-identify as female,
and about 10% less participants that experienced the storm. Respondents for Florence are
also less confident that their responses will be considered or lead to actual policy changes.
Individuals in Florence also have a higher average long-term risk perception. All of these
differences are significant at the 0.01% (two-sided t-test). Out of Control Set 1, however, it
15
appears that respondents evacuated at a similar rate (about 18% for both samples).
In addition, respondents in Florence are on average 5 years older, show a higher rate of
ownership, report higher average short-term (5-year) risk perception, and a higher average
hurricane insurance awareness. Florence also has a lower fraction of respondents reporting
having experienced damages due to the storm, and report a lower household size in average.
All of these differences are statistically significant at least at the 95% confidence level (two-
sided t-test). There are no detectable differences between the samples in terms of awareness
of FEMA and NFIP.
To put some of these figures in perspective, it is useful to map how the respondents
were affected by both storms. In Figure 5, we presents the spatial patterns for the rate
of evacuation, and the mode of the self-reported losses in the sample. Panel a) shows that
evacuations were more prevalent in coastal areas. However, inland counties in the path of the
storms experienced partial evacuation as well. In terms of losses, panel b in Figure 5 shows
that self-reported capital losses are widely distributed across the sample, but total losses
are more prevalent for coastal counties hit by Michael in the panhandle. In fact, comparing
the unconditional mean reported losses suggest that they were larger for the Michael sample
(p < 0.001 for a two-sided t-test).
Figure 5: Loss and Evacuation Maps. This map displays participant responses to evacuationand total loss questions in the survey. Map (a) depicts the percent of respondents who evacuated withina county (percent represents the survey sample). Map (b) displays total losses (categorized) for surveyrespondents that directly experienced either of the hurricanes. Those who did not directly experience thestorm were not presented with a loss question.
16
Building on these cross-sectional data, we now turn to the econometric analysis of survey
responses. The goal is to derive the willingness to pay (WTP) for improvements to hurricane
forecast accuracy across each of the three dimensions of forecasting (i.e., track, wind speed
and precipitation).
6.2 Contigent Valuation
This section reports the results for the contingent valuation method implemented to elicit the
WTP for improvements along different attributes of a hurricane forecast. We split this section
by forecast attribute. Table 2 reports the results for the maximum likelihood estimation in
the case of improvements in track forecast. The results for the full sample indicate a positive
and statistically significant unconditional mean WTP for an improved track forecast of $42.53
(Constant). Nonetheless, WTP significantly decreases if the attribute is shown later in the
survey (Order). The point estimate is a $4.78 penalty for the attribute being shown second,
and a penalty of $9.56 when it is show third, respectively. The point estimate for the rate of
improvement is positive, although small in magnitude and not statistically significant (Rate).
Including Control Set 1 in the estimation gives us some further insights regarding track
forecast improvements (Table 2). First, the effect of Order and Rate remain robust to
this specification. Second, WTP increases for respondents with higher income, for female
respondents, by having experienced the storm, and by having evacuated during the storm.
All of these estimates are significant, at least at the 95 percent confidence level. Second, WTP
increases if the respondent believes that the survey will be considered by authorities (Voice),
and if they believe it will effectively lead to policy changes (Action). Finally, WTP also
increases if the respondent has a higher long-term risk perception (likelihood of experiencing
a hurricane in the next ten years, Long-term Risk). These last three estimates are all
relatively high in magnitude and highly statistically significant.
Finally, Table 2 shows the estimates for including both Control Set 1 and Control Set 2
in the estimation. The result shows that this additional battery of controls does not alter
the relative magnitude and significance of the previous estimates. The only exception is the
estimate for long-term risk perception, which increases from $6.70 to $10.34. In other words,
it seems like Control Set 1 captures much of the variation observed in the survey.
When examining both samples separately, however, some differences arise. In the case
of Florence, Table 2 shows that while most estimates remain relatively stable and robust
when compared to the full sample, there is a loss of precision for the effect of being female
and having evacuated during the storm. In the case of Michael, it shows a further loss in
precision in the estimates for Control Set 1, and only evacuation, action, and long-term risk
17
Table 2: Regression Results for Improvements in Track Forecast
Full Sample Florence Michael
Order -4.78∗∗∗ -4.79∗∗∗ -4.88∗∗∗ -5.08∗∗∗ -5.12∗∗∗ -5.25∗∗∗ -4.13∗∗ -4.02∗∗ -3.96∗∗
(0.73) (0.72) (0.72) (0.87) (0.85) (0.86) (1.34) (1.33) (1.33)
Rate 0.65 0.65 0.82 0.70 0.49 0.50 0.54 1.14 1.71(0.73) (0.72) (0.72) (0.87) (0.86) (0.87) (1.32) (1.32) (1.32)
Control Set 1
Income 0.11∗∗∗ 0.09∗∗ 0.11∗∗ 0.09∗ 0.10 0.08(0.03) (0.03) (0.04) (0.04) (0.06) (0.06)
Female 3.32∗∗ 3.40∗ 2.80 3.11∗ 4.63 4.04(1.29) (1.32) (1.50) (1.55) (2.49) (2.55)
Experience 5.18∗∗ 4.00∗ 5.42∗∗ 4.88∗ 5.79 2.92(1.65) (1.73) (1.84) (1.92) (3.80) (3.97)
Evacuated 3.70∗ 3.21∗ 2.21 1.99 7.05∗ 6.08∗
(1.57) (1.61) (1.85) (1.92) (2.98) (3.00)
Voice 2.71∗∗∗ 2.87∗∗∗ 3.10∗∗∗ 3.26∗∗∗ 1.91 1.96(0.62) (0.63) (0.75) (0.76) (1.12) (1.12)
Action 4.46∗∗∗ 4.50∗∗∗ 4.23∗∗∗ 4.40∗∗∗ 5.01∗∗∗ 4.92∗∗∗
(0.65) (0.66) (0.79) (0.80) (1.17) (1.16)
Long-term Risk 6.70∗∗∗ 10.34∗∗∗ 5.95∗∗ 10.06∗∗ 9.23∗ 11.56∗
(1.81) (2.70) (2.04) (3.14) (3.94) (5.32)
Constant 42.53∗∗∗ 7.35 6.25 42.94∗∗∗ 8.57 5.77 41.68∗∗∗ 3.55 4.89(2.16) (3.77) (4.41) (2.58) (4.48) (5.31) (3.97) (7.19) (8.14)
Observations 4650 4644 4581 3150 3148 3117 1500 1496 1464Log-Likelihood -5264.57 -5131.73 -5045.45 -3571.41 -3478.03 -3437.84 -1692.15 -1650.17 -1600.06χ2 43.55 249.74 263.46 34.71 181.48 188.66 9.65 72.89 84.84Control Set 2 X X X
Robust standard errors in parentheses∗ p < 0.05, ∗∗ p < 0.01, ∗∗∗ p < 0.001
Notes: The unit of of observation is an individual respondent. The table is split into three panels. Each panel works with adifferent sample: all respondents (Full Sample), only those residing in areas affected by Florence (Florence), and only thoseaffected by Michael (Michael). Each column is a different estimation. Order represents the order in which the track attributewas shown to the respondent and takes values from 1 to 3. Rate is the rate at which the errors of the forecast product arereduced in the next decade. Income is the average yearly income in the respondent’s zip code. Female is a binary indicator ifthe respondent self-identifies as a female. Experience and evacuated are binary variables indicating if the respondent declared tohave experienced the storm and/or is she evacuated, respectively. Voice and Action are categorical variables taking values from1 to 5 depending on their beliefs that the survey will be considered by the authorities and if the results will lead to actual policychange, respectively. Long-tern risk is the perceived change that the respondent will experience a hurricane in the next fiveyears. Control Set 2 includes controls for age, house ownership, length of residence in current household, short-term hurricanerisk perception, awareness of insurance programs, evacuation decisions, damages experienced, and household size.
remain significant under the different specifications. These disparities are further evidence
that there are underlying differences across samples. In other words, the characteristics of a
given storm appear to have a strong influence when it comes to what is considered valuable
information ex-post. The full report of coefficient estimates is available in Table A.1 in the
18
Appendix.
We now turn to examine the results for the contingent evaluation for improvements in
wind speed forecast, which are shown in Table 3. Overall, the results suggest a similar
pattern as with improvements in track: large unconditional valuation for improvements, a
penalization for the attribute being shown later in the survey, and no measurable effect of
the rate of improvement. This pattern is consistent for both the full and the individual
samples.
Including the sets of controls, however, results in a loss of precision for the effect of female
respondents and their long-term risk perceptions in the full sample (Table 3). Despite this
problem, statistically significant estimates remain consistent and intuitive when compared
to the analysis on track forecast improvement. That is, the WTP increases for respondents
with higher income, by having experienced the storm, by having evacuated during the storm,
and by believing the survey will be considered and implemented in future policy changes.
Long-term risk beliefs are only significant in the fully specified model model, but are still
consistent with the idea that respondents who think they are more likely be hit by a hurricane
in the next ten years are also willing to pay more for a more accurate wind speed forecast.
Breaking down these estimates by sample suggest a similar pattern. The main difference
however, is that having experienced the storm has a higher valuation in the Michael sample
(Table A.2). This finding could be related to that fact that most of the impacts from Michael
were due to strong winds, but also due to the physical geography of the Florida panhandle
facilitating evacuation, since driving an hour due north improves safety in the face of the
storm. Arguably, in the case of Michael, the forecast entered into evacuation decisions more
easily. In the case of Florence, even if an individual knew that they would experience the
storm, the best decision might still be to stay home rather than risk a flash flood encounter.
In addition, both samples’ WTP increases as the respondents believe the survey will be
considered and cause policy changes by the agency. The full report of coefficient estimates
is available in Table A.2, which is also included in the Appendix.
Finally, we cover the results of the maximum likelihood estimation for improvements
in the precipitation forecast, which are shown in Table 4. Much like the two previous
sets of results, there is also a somewhat large unconditional valuation for improvements,
a penalization for the attribute being shown later in the survey, and no effect measurable
effect of the rate of improvement. This pattern is again consistent for both full and individual
samples.
Focusing on the full sample, it is important to highlight that there is a consistent decrease
in the magnitude of the estimates, when compared to the WTP for better wind speed
forecasts. Moreover, both income and long-term risk perception are no longer statistically
19
Table 3: Regression Results for Improvements in Wind Speed Forecast
Full Sample Florence Michael
Order -4.24∗∗∗ -4.11∗∗∗ -3.93∗∗∗ -4.99∗∗∗ -4.86∗∗∗ -4.64∗∗∗ -2.78∗ -2.73∗ -2.66∗
(0.76) (0.74) (0.75) (0.96) (0.93) (0.94) (1.27) (1.25) (1.26)
Rate 0.46 0.32 0.37 0.40 0.24 0.24 0.52 0.38 0.33(0.76) (0.74) (0.75) (0.95) (0.92) (0.93) (1.26) (1.23) (1.25)
Control Set 1
Income 0.10∗∗ 0.10∗∗ 0.11∗∗ 0.12∗∗ 0.06 0.04(0.03) (0.03) (0.04) (0.04) (0.05) (0.06)
Female 1.37 1.46 1.33 1.43 1.66 1.25(1.35) (1.39) (1.64) (1.69) (2.38) (2.46)
Experience 6.23∗∗∗ 5.47∗∗ 5.22∗∗ 5.19∗ 10.38∗∗ 8.12∗
(1.73) (1.82) (2.02) (2.11) (3.63) (3.83)
Evacuated 5.96∗∗∗ 5.48∗∗ 6.17∗∗ 5.74∗∗ 5.26 4.82(1.64) (1.69) (2.03) (2.11) (2.78) (2.85)
Voice 4.26∗∗∗ 4.21∗∗∗ 4.87∗∗∗ 4.71∗∗∗ 3.20∗∗ 3.15∗∗
(0.66) (0.66) (0.83) (0.84) (1.06) (1.08)
Action 4.24∗∗∗ 4.38∗∗∗ 4.53∗∗∗ 4.77∗∗∗ 3.62∗∗∗ 3.64∗∗
(0.68) (0.69) (0.87) (0.88) (1.10) (1.11)
Long-term Risk 3.03 6.33∗ 3.33 6.96∗ 2.73 4.51(1.87) (2.84) (2.21) (3.41) (3.63) (5.22)
Constant 38.30∗∗∗ 0.65 -0.71 39.91∗∗∗ 0.25 -3.64 35.35∗∗∗ 0.22 2.05(2.27) (3.98) (4.61) (2.87) (4.97) (5.89) (3.68) (6.74) (7.65)
Observations 4650 4644 4581 3150 3148 3117 1500 1496 1464Log-Likelihood -5315.78 -5163.08 -5071.72 -3534.25 -3416.75 -3365.09 -1780.16 -1741.95 -1698.36χ2 31.21 278.22 283.58 27.60 210.96 214.35 4.89 69.62 76.89Control Set 2 X X X
Robust standard errors in parentheses∗ p < 0.05, ∗∗ p < 0.01, ∗∗∗ p < 0.001
Notes: The unit of of observation is the voting decision made by an individual respondent. The table is split into three panels.Each panel works with a different sample: all respondents (Full Sample), only those residing in areas affected by Florence(Florence), and only those affected by Michael (Michael). Each column is a different estimation. Order represents the order inwhich the track attribute was shown to the respondent and takes values from 1 to 3. Rate is the rate at which the errors ofthe forecast product are reduced in the next decade. Income is the average yearly income in the respondent’s zip code. Femaleis a binary indicator if the respondent self-identifies as a female. Experience and Evacuated are binary variables indicating ifthe respondent declared to have experienced the storm and/or is she evacuated, respectively. Voice and Action are categoricalvariables taking values from 1 to 5 depending on their beliefs that the survey will be considered by the authorities and if theresults will lead to actual policy change, respectively. Long-tern risk is the perceived change that the respondent will experiencea hurricane in the next five years. Control Set 2 includes controls for age, house ownership, length of residence in currenthousehold, short-term hurricane risk perception, awareness of insurance programs, evacuation decisions, damages experienced,and household size.
significant. Breaking down the analysis by sample is consistent with this story as well.
The only coefficients that remain significant across the spectrum, are voice and action,
respectively (TableA.2). In other words, the most consistent controls associated with higher
20
Table 4: Regression Results for Improvements in Precipitation Forecast
Full Sample Florence Michael
Order -5.09∗∗∗ -5.21∗∗∗ -5.26∗∗∗ -4.81∗∗∗ -4.85∗∗∗ -4.95∗∗∗ -5.71∗∗∗ -5.96∗∗∗ -5.75∗∗∗
(0.82) (0.81) (0.81) (1.00) (0.98) (0.99) (1.44) (1.43) (1.44)
Rate 0.27 0.44 0.63 0.04 0.00 0.11 0.75 1.27 1.43(0.81) (0.79) (0.80) (0.99) (0.96) (0.97) (1.41) (1.40) (1.41)
Control Set 1
Income 0.06 0.06 0.06 0.07 0.03 0.01(0.03) (0.03) (0.04) (0.04) (0.06) (0.06)
Female 4.10∗∗ 3.68∗ 5.29∗∗ 4.73∗∗ 1.60 0.76(1.44) (1.48) (1.72) (1.77) (2.65) (2.74)
Experience 4.09∗ 4.09∗ 4.15∗ 3.99 5.90 5.86(1.84) (1.93) (2.10) (2.18) (4.07) (4.31)
Evacuated 4.22∗ 3.92∗ 3.38 2.78 5.61 5.83(1.74) (1.79) (2.10) (2.18) (3.09) (3.17)
Voice 4.25∗∗∗ 4.34∗∗∗ 5.07∗∗∗ 5.18∗∗∗ 2.74∗ 2.75∗
(0.70) (0.71) (0.87) (0.88) (1.18) (1.20)
Action 4.83∗∗∗ 4.70∗∗∗ 4.72∗∗∗ 4.51∗∗∗ 5.03∗∗∗ 4.84∗∗∗
(0.73) (0.74) (0.90) (0.92) (1.24) (1.24)
Long-term Risk 1.15 4.70 1.05 5.17 1.10 3.65(1.99) (3.01) (2.31) (3.54) (4.07) (5.80)
Constant 39.31∗∗∗ 3.55 4.90 39.35∗∗∗ 1.45 5.33 39.24∗∗∗ 7.62 4.98(2.41) (4.22) (4.90) (2.96) (5.16) (6.14) (4.15) (7.50) (8.47)
Observations 4650 4644 4581 3150 3148 3117 1500 1496 1464Log-Likelihood -5495.70 -5343.76 -5261.78 -3710.59 -3597.80 -3547.07 -1784.84 -1741.40 -1705.47χ2 38.63 265.24 272.82 23.27 197.87 204.69 15.80 72.66 79.58Control Set 1 X X X X X XControl Set 2 X X X
Robust standard errors in parentheses∗ p < 0.05, ∗∗ p < 0.01, ∗∗∗ p < 0.001
Notes: The unit of of observation is the voting decision made by an individual respondent. The table is split into three panels.Each panel works with a different sample: all respondents (Full Sample), only those residing in areas affected by Florence(Florence), and only those affected by Michael (Michael). Each column is a different estimation. Order represents the order inwhich the track attribute was shown to the respondent and takes values from 1 to 3. Rate is the rate at which the errors ofthe forecast product are reduced in the next decade. Income is the average yearly income in the respondent’s zip code. Femaleis a binary indicator if the respondent self-identifies as a female. Experience and Evacuated are binary variables indicating ifthe respondent declared to have experienced the storm and/or is she evacuated, respectively. Voice and Action are categoricalvariables taking values from 1 to 5 depending on their beliefs that the survey will be considered by the authorities and if theresults will lead to actual policy change, respectively. Long-tern risk is the perceived change that the respondent will experiencea hurricane in the next five years. Control Set 2 includes controls for age, house ownership, length of residence in currenthousehold, short-term hurricane risk perception, awareness of insurance programs, evacuation decisions, damages experienced,and household size. Sample sizes differ due to missing responses.
WTP are related to the trust that the agency will consider the survey and will trigger some
policy change. The full set of estimates is also shown in the Appendix in Table A.3.
21
Overall, these results present us with several insights. First, all rates of improvement for
all attributes are valued by the respondents. Second, respondents are insensitive (in terms of
statistical significance) to changes in the rates tested. In other words, there is a demand for
improving track, wind speed and precipitation forecast. Third, while the effect of the different
controls mostly goes in the expected direction, trusting that the respondents’ opinion will
lead to actual policy changes is the only factor that is robust across all different attributes
and samples. This pattern suggest that credible public feedback is strongly associated with
a higher WTP for forecast products. Finally, it is also worth noting that there are obvious
differences across all different attributes and samples. Again, these differences indicate that
the experiences of the respondents are likely to have a major impact on their perceived value
of different forecast products.
Accordingly, we now turn to estimate the average WTP for different forecast products
and across samples. To do so, we implement equation 9 limited to statistically significant
coefficients in the previous estimations. The average progress is circumscribed to the 72-hour
prior landfall time window, and assumes a 40% error reduction in storm track, a 29% error
reduction in wind speed, and a 42% error reduction in precipitation forecast, respectively.
These results are shown in Table 5.
Table 5: Average Willingness to Pay for Hurricane Forecast Improvement
Full Sample Florence Michael
WTP (Track) 33.01∗∗∗ 25.74∗∗∗ 26.10∗∗∗ 32.82∗∗∗ 22.55∗∗∗ 24.67∗∗∗ 33.44∗∗∗ 8.31∗ 11.39∗∗
(1.57) (3.48) (3.56) (1.88) (3.98) (4.24) (2.89) (4.18) (4.38)
WTP (Wind speed) 29.77∗∗∗ 27.87∗∗∗ 28.91∗∗∗ 29.87∗∗∗ 28.74∗∗∗ 30.86∗∗∗ 29.75∗∗∗ 21.78∗∗∗ 22.90∗∗∗
(1.64) (3.51) (3.61) (2.06) (4.37) (4.50) (2.71) (4.71) (5.02)
WTP (Precipitation) 29.17∗∗∗ 21.36∗∗∗ 16.59∗∗∗ 29.77∗∗∗ 24.18∗∗∗ 19.80∗∗∗ 27.87∗∗∗ 9.05∗ 8.97∗
(1.77) (2.88) (3.55) (2.16) (3.50) (3.09) (3.08) (3.93) (4.01)Observations 4650 4644 4581 3150 3148 3117 1500 1496 1464Control Set 1 X X X X X XControl Set 2 X X X
Standard errors in parentheses∗ p < 0.05, ∗∗ p < 0.01, ∗∗∗ p < 0.001
Notes: The unit of of observation is an individual respondent. The table has three panels of three columns each. Each panelworks with a different sample: all respondents (Full Sample), only those residing in zip codes affected by Florence (Florence),and only those affected by Michael (Michael). Control Set 1 includes control for income, female respondents, having experiencedthe storm, having evacuated for the storm, the belief that the survey findings will be considered by the relevant agencies, thebelief that the survey will lead to actual policy adjustments, and the self-assessed chance of experiencing a hurricane in thenext ten years. Control Set 2 includes controls for age, house ownership, length of residence in current household, short-termhurricane risk perception, awareness of insurance programs, evacuation decisions, damages experienced, and household size.Sample sizes differ due to missing responses.
Table 5 shows a non-zero valuation for improvements across all attributes and samples.
This result is robust in all specifications. Consider the fully specified estimation in the full
sample. Respondents are, in average, willing to pay $26.10, $28.91, and $16.59 in additional
22
household taxes per year for the next ten years for improvements in track, wind speed
and precipitation forecasts, respectively. All three estimates are significant at the 1% level.
Importantly, the attribute with the biggest WTP across the sweep of results, is wind speed.
Breaking down the estimates by sample, however, reveals that the average WTPs differs
across the two regions in the sample. In particular, Florence has a higher average WTP for
every attribute evaluated.
These differences should come as no surprise. We previously found that there are system-
atic differences in the characteristics of both samples, particularly for income levels. These
differences were present in the coefficient, and thus manifest in the WTP as well. For in-
stance, differences in coefficient for track and wind speed explain a difference of about $8
across both samples. Differences in the WTP for precipitation, however, are not explained
by income differences, but the female composition of the sample and individual responses.
Further, when comparing intra-samples and using wind speed as the reference, track and pre-
cipitation WTPs are relatively much more valued in Florence (0.79 and 0.64, respectively)
than in Michael (0.49 and 0.39, respectively).
Intuitively, this suggests an anchoring effect following each storm, which would have
elevated WTP for improved rainfall prediction for those who experienced Florence, and
elevated WTP for wind speed forecast improvements by those who experienced Michael. Our
results are consistent with a hypothesis of anchoring. To address this issue, we evaluated the
effect of including a storm fixed effect in the full sample, and found no major or significant
changes in the estimates. Below, we provide a framework to interpret these results in a
national context. Sample sizes differ due to missing responses.
6.3 Extrapolation
In the previous section we derived the average willingness to pay for improvements to the
hurricane forecast along three of its dimensions. Extrapolating these results to out-of-sample
individuals, however, requires a mechanism to account for the fact that our sample targets
communities affected by either Florence or Michael. Our approach is to perform this exercise
at the household level.
In particular, we take the fully specified WTP for an attribute in the full sample and
assume the average respondent is representative of households in the sampled regions. Im-
plicitly, we are also assuming that in average, the forecast keeps improving by ±20% relative
to the rate of improvement occurred between 2008-2018. This assumption is plausible, based
on the previous result that any and all improvements are strictly positively valued, regardless
of the actual rate of improvement.
23
As an illustration, we extrapolate the WTP for improvements in wind speed forecast.
Using the census data we then scale the WTP of $28.91 by the number of occupied household
in the counties present in the sample. This exercise is shown in panel a) of Figure 6.
Aggregating these by-county WTPs suggest a total WTP of about $67 million per year for
the surveyed region. Further, we can extend this exercise to all counties having experienced
wind speeds of at least 30 miles per hour due to a hurricane between 2006-2018 in the
continental US. Spatially, this exercise is shown in panel b) of Figure 6. The total WTP
considering these hurricane exposed counties is about $1.18 billion.
Figure 6: Sample and Extrapolated Willingness to Pay for Wind Speed Forecast.The figure shows the aggregated willingness to pay (WTP) for wind speed forecast improvement. Panel a)extrapolates the household WTP for counties present in the survey, while panel b) extrapolates WTP toevery county that has experienced at least 30 miles per hour wind due to a hurricane between 2006-2018.WTP is log-adjusted to control for counties with disproportionally large number of occupied households.
On a per-capita basis, these numbers are equivalent to a WTP of $13.96 per adult per
year in additional taxes. Extending this payment over ten years, as stated in the survey, and
discounting at 5% gives a total net present WTP of $113 per adult. Similar calculations for
the other two forecast attributes are included in Table 6. These calculations indicate that
the net present value WTP for track and precipitation forecast improvements are $102.15
and $64.94, respectively.
The projection of the WTP to the vulnerable population is straight forward. Nevertheless,
coastal and inland regions are not equally exposed to intensity and frequency of hurricanes,
which in turn implies the decision on the wind speed threshold will have sizable implications
24
Table 6: Selected Willingness to Pay for Hurricane Forecast Improvement
Average Estimate Counties in Survey Vulnerable Counties Per-capita NPV(USD/hh/year) (USD/year) (USD/year) (USD/year/person) (USD/person)
Storm Track $26.10 $60.9×106 $1,031×106 $12.60 $102.15Wind Speed $28.91 $67.4×106 $1,142×106 $13.96 $113.18Precipitation $16.59 $38.7×106 $655×106 $8.01 $64.94
Notes: All monetary units are in 2018 USD. Extrapolation based on the number of households (hh) occupied as reported in the2018 census. Vulnerable counties are those that have experienced at least 30 miles per hour wind due to a hurricane between2006 and 2018. Per-capita values only consider individuals over 18 years old as per the 2018 census, and future values arediscounted at 5% per year.
in the extrapolated total WTP. Consequently, we report these calculations for thresholds
at 20, 30, 40 and 50 miles per hour, respectively. Spatially, the WTP for improved wind
forecast in vulnerable counties under these different thresholds is shown in Figure 7. As
expected, the lower the wind speed threshold, the greater the area identified as vulnerable.
Bearing this implications in mind, the relevant WTP calculations for all of these thresholds
are shown in Table 7.
Table 7: Extrapolation of Willingness to Pay for Hurricane Forecast Improvement
> 50 mph > 40 mph > 30 mph > 20 mph
Total WTP (USD×106/year)
Storm Track $409 $617 $1,031 $1,566Wind Speed $453 $684 $1,142 $1,735Precipitation $260 $392 $655 $995
Per-capita WTP (USD/year/person)
Storm Track $12.33 $12.50 $12.60 $12.71Wind Speed $13.65 $13.85 $13.96 $14.08Precipitation $7.83 $7.95 $8.01 $8.08
NPV (USD/person)
Storm Track $99.96 $101.35 $102.16 $103.05Wind Speed $110.67 $112.29 $113.19 $114.16Precipitation $63.48 $64.46 $64.94 $65.51
Notes: All monetary units are in 2018 USD. Extrapolation based on the number of households occupied as reported in the 2018census. Vulnerable counties are those that have experienced at least 20, 30, 40, and 50 miles per hour wind due to a hurricanebetween 2006 and 2018, respectively. Per-capita values only consider individuals over 18 years old as per the 2018 census, andfuture values are discounted at 5% per year.
It is important to note, however, that although the three forecast attributes are treated
separately and ranked differently, all three of them are intertwined in reality. For example,
if hurricane research looking at internal processes, air-sea interactions, or sensitivity to wind
shear leads to an improvement to track forecasts, it should also lead to better intensity
25
Figure 7: Extrapolated Willingness to Pay for Wind Speed Forecast. The figureshows the aggregated willingness to pay (WTP) for forecast improvement. Panels a), b), c), and d) showthe extrapolated WTP to every county that has experienced at least 20, 30, 40, and 50 miles per hourwinds due to a hurricane between 2016-2018, respectively. WTP is log-adjusted to control for counties withdisproportionally large number of occupied households.
and rainfall forecasts. This suggest that joint improvements are likely to follow traditional
research efforts, and thus compound the value of improvements across different attributes.
The problem, however, is that these compounded values will not be additively separable.
Nonetheless, the purpose of this study is to understand preferences for these components as
primary attributes. Moreover, eliciting responses for each attribute separately makes it more
tractable to the respondents and is still useful when considering funding advances in these
areas. Therefore, and bearing in mind these potential confounding sources of valuation, the
26
extrapolation exercise Table 7 suggest the more conservative lower bounds to the willingness
to pay for forecast improvement are $453 million per year for wind speed, $409 million
per year for storm track, and $260 million a year for precipitation. Any efforts resulting
improvements across multiple dimensions are likely to be even more valuable than these
individual estimates.
7 Discussion
We analyze the perceived valuation of forecast improvement across space, time and forecast
attributes. We document the plausible policy argument for why decision makers may assign
value to such improvements, and then test for the existence of that value in two regions
recently affected by hurricanes. We find that improvements in forecast accuracy are strictly
positively valued, but insensitive to the rate of improvement. Among all three attributes,
improvements in wind speed forecasts are the most valued. In aggregate, our main results
calculate that maintaining the prior decade’s rate of wind speed forecast error reduction is
valued at about $1.14 billion per year in all hurricane-prone counties in the US. Storm track
and precipitation forecast improvements are valued at about $1.03 billion and $655 million
per year, respectively.
We recognize that improvements in track, intensity and rain forecasts have interlinkages
at the operational levels but the purpose of this study is to understand public references
for these components as separate key primary attributes. The hurricane risk information is
a complex product which is not exchanged frequently in a regular market set-up to allow
consumers have a well-defined preference structure. While understanding the complexities
and interlinkages are important factors to consider, given the unique nature of this product
we had to draw a balance to present these attributes in a manageable way and elicit corre-
sponding values that will be relevant for decision-makers. Because of these interlinkages, our
separate estimates are likely lower bounds for research efforts that result in a wide array of
forecast improvements. These bounds are useful for future cost-benefit analyses seeking to
establish the societal benefit of scientific and operational efforts to further improve hurricane
modeling and forecasting research.
To achieve these results, we integrate hurricane forecast error statistics with a contingent
valuation method. By targeting areas in which respondents are already familiar with the
National Hurricane Center forecast products, they are able to give a more reasoned reply
when presented with the hypothetical improvement scenarios from the atmospheric models.
Economic theory suggests that if better information allows them to take better decisions in
terms of adaptive behavior in the face of a hurricane, then there would be an associated value
27
assigned to having an improved forecast. This argument, however, requires that forecasts
actually influence adaptive behavior, such as evacuation and the purchase of emergency
supplies. Our results provide quantitative evidence that this relationship exists.
In particular, the magnitudes of our WTP estimates (roughly $16-$26 per household per
year) exceed those of Lazo and Waldman (2011), $13 per household per year or $15 after
adjusting for inflation, which may stem from our different methodological approaches. In
fact, a strength of this study is that the analysis is based on a large representative sample size.
Earlier studies focused on this topic are usually based on a smaller and non-representative
sample. For instance, the stated preference study by Lazo and Waldman (2011) values
improved hurricane forecasts in the US using a sample size of only 80 respondents from
the Miami-Fort Lauderdale Metropolitan area. Similarly, Ahsan et al. (2020) estimates
household’s willingness to pay for improved cyclone warning services in Bangladesh based
on a sample 490 households, while Nguyen et al. (2013) do so in Vietnam using responses
from 1014 households. Our approach is a large-scale randomized, double-bounded contingent
evaluation. Our sample of 4650, drawn from two regions, is both more granular and allows
us to control for several observables. Thus, the difference is not surprising.
Our analysis provides evidence of a value of improving hurricane forecasts, but several
caveats remain. First, we use observed forecast errors of track and wind speed during the
prior decade to inform what forecast errors could be a decade in the future. In particular,
a linear trend line through errors from 2008 to 2018 yields an average percent improvement
during that decade. We project that same percentage forward to 2028 as the “status quo”
scenario and then build our relative scenarios of improvement around that baseline. The
implicit assumption is that forecasts made in 2028 will not only be more accurate than those
made in 2018, but also have less uncertainty surrounding them. While the choice of a specific
decade as the baseline is arbitrary, we assert that all three scenarios are plausible for both
track and intensity, and that the results would not differ noticeably if some other length of
time was used to construct the error reduction values.
The precipitation model is more complicated and involves many more assumptions, ac-
cordingly. Track and intensity metrics can be adjusted independent of each other; however,
rainfall is inherently tied to both of them. Further, the National Hurricane Center does not
make forecasts of rainfall swaths for hurricanes as part of its six-hourly advisory packages,
and therefore, there are no official annual average errors of rainfall forecasts. To create
self-consistent rainfall forecasts from the two hurricanes (Florence and Michael) and four
scenarios (2018 and three for 2028), we use a parametric precipitation model that accounts
for the hurricane’s intensity, size, and track as well as the environmental vertical wind shear
and topographic effects (Lonfat et al., 2007). Of course, a parametric model is imperfect
28
because it is built on empirical relationships and is not a full-physics four-dimensional nu-
merical weather prediction model, but it has the advantage of treating each hurricane and
its limited set of attributes in an identical fashion.
Rather than just nudging the parametric precipitation model with slightly different track
and intensity values for each of the scenarios, we explore probabilistic forecasts using the
National Hurricane Center’s 1000-member Monte-Carlo ensemble. The spread of realizations
within the ensemble takes into consideration the observed error characteristics of intensity,
track, and size. In addition to the real-time ensembles created in 2018, we also acquire
ensembles that used the track and intensity values from the hypothetical future scenarios.
This approach allows us to run the parametric rainfall model on each member of each of the
ensembles, calculate probabilistic information, and evaluate the likelihood of over- or under-
forecasting rainfall by a specified amount relative to what a “deterministic” operational
rainfall forecast would have been. While these preparations are indeed modeling and time
intensive, we deem them necessary to approach the actual forecast products that individuals
would see under different rates of improvement.
In addition and since contingent valuation relies on stated values for what people would
pay instead of estimating how much they actually do pay, it can be biased. One possibility is
strategic bias, which occurs when people deliberately misstate their WTP in order to improve
their net benefits from any anticipated policy change. To control for strategic bias, we
include questions in our survey about whether respondents believed their replies might have
any influence on policy. Another possibility is embedding, which occurs when respondents
state that they are willing to pay the same amount for goods that differ in quality or different
amounts for the same good (Carson et al., 1995). To control for this bias, we randomized
the order in which the attributes were shown to the respondents, and we find sufficient
variation in our WTP estimates across attributes to dismiss concerns about embedding. A
third concern is hypothetical bias, which occurs when respondents are unfamiliar with the
good or service being valued. Because our sample targeted those who had recently come
under a tropical storm warning, our respondents are familiar with hurricane forecasts, thus
minimizing the chance for hypothetical bias.
Despite these caveats, the results in the analysis are clear and consistent, with noticeable
implications for policy making. Namely, the public values further improvement, even after
the remarkable progress observed since the start of the Hurricane Forecast Improvement
Project in 2007. This important result is encouraging, and highlights the relevance of the
ongoing efforts to make the forecast even more accurate. Nonetheless, our results also raise
a question for the adequacy of the mandated standards that focus on track and wind speed.
While justifiable in political discourse, it is unclear if such goals would pass a cost-benefit
29
analysis for optimal allocation of public resources. This analysis sheds a light on this problem
and provides figures that can be implemented in such evaluation.
Amongst all three attributes, improvements in wind speed forecasts are consistently and
robustly valued higher. This result is perhaps related to the way in which respondents process
different sources of forecast information. On the one hand, wind speed is directly related
to the well-known Saffir-Simpson category of a storm, which is both single-dimensional and
directly related to the damages associated with a given hurricane. Arguably, this measure
allows an individual to rapidly assess the potential danger of a storm and engage in adaptive
behavior accordingly. If true, the decision maker’s relative ease in thinking about wind
speed is an availability effect and is important even if wind speed is not objectively the
most threatening hurricane attribute to human life. Moreover, categories are often used in
the media as well, so individuals are more familiar with that index. Track and precipitation
forecast on the other hand, are not as effective in describing the potential damage of a storm.
In addition, individuals may not even understand how to interpret these forecasts in the first
place. Our results provide partial evidence for this potential linkage.
Another noteworthy result is the attitude respondents display when it comes to their
voices reaching policy makers. The survey being considered by the agency, as well as the
likelihood of actual policy adjustments had a positive and a statistically robust effect on vir-
tually all of our analyses. In our context, this is plausible evidence of a “signal mechanism.”
In other words, the more credible the communication vehicle, the more the incentive to com-
municate a signal to encourage agencies to provide the improvement without an actual tax
burden on their end. This result would be consistent with previous evidence in contingent
valuation studies (Carson et al., 1995). Unfortunately, we are unable to completely resolve
this caveat with this, or any survey mechanism, and advise to consider this pattern carefully
when interpreting our results.
Finally, we believe one of the main contributions of this paper is the demonstration
of the potential for further interdisciplinary collaborations in hurricane research, but in
other fields as well. Our study differentiates itself from previous attempts to measure the
value of improving hurricane forecasts by integrating the key insights of both atmospheric
science and the stated preferences literature. To our knowledge, this is the first time such
effort has been implemented for a large-scale survey. The robust findings gives us enough
confidence that the estimated values can be worth considering in analyzing policy options
for future hurricane research fund allocation. We are confident that this multi-disciplinary
(i.e., atmospheric science - economics) approach was necessary for this study, but other
policy-relevant question will greatly benefit from other integrative approaches.
30
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33
A Estimation Tables
This section reports the full estimation tables for the results reported in Section 6.
Table A.1: Full Regression Results for Improvements in Track Forecast
Full Sample Florence Michael
BetaOrder -4.78∗∗∗ -4.79∗∗∗ -4.88∗∗∗ -5.08∗∗∗ -5.12∗∗∗ -5.25∗∗∗ -4.13∗∗ -4.02∗∗ -3.96∗∗
(0.73) (0.72) (0.72) (0.87) (0.85) (0.86) (1.34) (1.33) (1.33)
Rate 0.65 0.65 0.82 0.70 0.49 0.50 0.54 1.14 1.71(0.73) (0.72) (0.72) (0.87) (0.86) (0.87) (1.32) (1.32) (1.32)
Income 0.11∗∗∗ 0.09∗∗ 0.11∗∗ 0.09∗ 0.10 0.08(0.03) (0.03) (0.04) (0.04) (0.06) (0.06)
Female 3.32∗∗ 3.40∗ 2.80 3.11∗ 4.63 4.04(1.29) (1.32) (1.50) (1.55) (2.49) (2.55)
Experience 5.18∗∗ 4.00∗ 5.42∗∗ 4.88∗ 5.79 2.92(1.65) (1.73) (1.84) (1.92) (3.80) (3.97)
Evacuated 3.70∗ 3.21∗ 2.21 1.99 7.05∗ 6.08∗
(1.57) (1.61) (1.85) (1.92) (2.98) (3.00)
Voice 2.71∗∗∗ 2.87∗∗∗ 3.10∗∗∗ 3.26∗∗∗ 1.91 1.96(0.62) (0.63) (0.75) (0.76) (1.12) (1.12)
Action 4.46∗∗∗ 4.50∗∗∗ 4.23∗∗∗ 4.40∗∗∗ 5.01∗∗∗ 4.92∗∗∗
(0.65) (0.66) (0.79) (0.80) (1.17) (1.16)
Long-term Risk 6.70∗∗∗ 10.34∗∗∗ 5.95∗∗ 10.06∗∗ 9.23∗ 11.56∗
Perception (1.81) (2.70) (2.04) (3.14) (3.94) (5.32)
Age 0.01 0.06 -0.08(0.04) (0.05) (0.07)
Owner 2.78∗ 1.43 5.37∗
(1.30) (1.57) (2.35)
Tenure -0.01∗ -0.01 -0.01(0.00) (0.01) (0.01)
Short-risk -5.61 -6.32 -2.28Perception (3.15) (3.63) (6.32)
Hurricane Ins. -0.28 -0.42 0.13Awareness (0.64) (0.77) (1.16)
FEMA 1.01 0.73 1.56Awareness (0.68) (0.80) (1.25)
NFIP -0.32 -0.45 0.01Awareness (0.61) (0.73) (1.13)
Damaged 1.76 0.94 3.70(1.35) (1.75) (2.31)
Household -0.24 0.09 -0.73Size (0.29) (0.38) (0.52)
Constant 42.53∗∗∗ 7.35 6.25 42.94∗∗∗ 8.57 5.77 41.68∗∗∗ 3.55 4.89(2.16) (3.77) (4.41) (2.58) (4.48) (5.31) (3.97) (7.19) (8.14)
SigmaConstant 33.07∗∗∗ 32.16∗∗∗ 32.04∗∗∗ 32.36∗∗∗ 31.35∗∗∗ 31.38∗∗∗ 34.62∗∗∗ 33.89∗∗∗ 33.22∗∗∗
(0.88) (0.85) (0.85) (1.03) (0.99) (1.00) (1.66) (1.63) (1.60)Observations 4650 4644 4581 3150 3148 3117 1500 1496 1464Log-Likelihood -5264.57 -5131.73 -5045.45 -3571.41 -3478.03 -3437.84 -1692.15 -1650.17 -1600.06χ2 43.55 249.74 263.46 34.71 181.48 188.66 9.65 72.89 84.84
Standard errors in parentheses+ p < 0.10, ∗ p < 0.05, ∗∗ p < 0.01, ∗∗∗ p < 0.001
Notes: The unit of observation is the voting decision made by an individual respondent. The table is split into three panels. Each panel workswith a different sample: all respondents (Full Sample), only those residing in areas affected by Florence (Florence), and only those affected by
Michael (Michael). Each panel reports all elements of β and σ. Sample sizes differ due to missing responses.
34
Table A.2: Full Regression Results for Improvements in Wind Speed Forecast
Full Sample Florence MichaelOrder -4.24∗∗∗ -4.11∗∗∗ -3.93∗∗∗ -4.99∗∗∗ -4.86∗∗∗ -4.64∗∗∗ -2.78∗ -2.73∗ -2.66∗
(0.76) (0.74) (0.75) (0.96) (0.93) (0.94) (1.27) (1.25) (1.26)
Rate 0.46 0.32 0.37 0.40 0.24 0.24 0.52 0.38 0.33(0.76) (0.74) (0.75) (0.95) (0.92) (0.93) (1.26) (1.23) (1.25)
Income 0.10∗∗ 0.10∗∗ 0.11∗∗ 0.12∗∗ 0.06 0.04(0.03) (0.03) (0.04) (0.04) (0.05) (0.06)
Female 1.37 1.46 1.33 1.43 1.66 1.25(1.35) (1.39) (1.64) (1.69) (2.38) (2.46)
Experience 6.23∗∗∗ 5.47∗∗ 5.22∗∗ 5.19∗ 10.38∗∗ 8.12∗
(1.73) (1.82) (2.02) (2.11) (3.63) (3.83)
Evacuated 5.96∗∗∗ 5.48∗∗ 6.17∗∗ 5.74∗∗ 5.26 4.82(1.64) (1.69) (2.03) (2.11) (2.78) (2.85)
Voice 4.26∗∗∗ 4.21∗∗∗ 4.87∗∗∗ 4.71∗∗∗ 3.20∗∗ 3.15∗∗
(0.66) (0.66) (0.83) (0.84) (1.06) (1.08)
Action 4.24∗∗∗ 4.38∗∗∗ 4.53∗∗∗ 4.77∗∗∗ 3.62∗∗∗ 3.64∗∗
(0.68) (0.69) (0.87) (0.88) (1.10) (1.11)
Long-term Risk 3.03 6.33∗ 3.33 6.96∗ 2.73 4.51Perception (1.87) (2.84) (2.21) (3.41) (3.63) (5.22)
Age -0.00 0.04 -0.05(0.04) (0.05) (0.07)
Owner 1.55 -0.60 5.43∗
(1.37) (1.73) (2.26)
Tenure -0.01 0.00 -0.01(0.00) (0.01) (0.01)
Short-term Risk -4.98 -5.58 -2.61Perception (3.32) (3.99) (6.10)
Hurricane Ins. -0.84 -0.86 -0.53Awareness (0.67) (0.84) (1.12)
FEMA 0.83 0.94 0.39Awareness (0.71) (0.88) (1.19)
NFIP 0.17 -0.18 0.92Awareness (0.64) (0.80) (1.08)
Damaged 2.28 1.97 2.57(1.42) (1.91) (2.21)
Household 0.15 0.67 -0.05Size (0.24) (0.43) (0.30)
Constant 38.30∗∗∗ 0.65 -0.71 39.91∗∗∗ 0.25 -3.64 35.35∗∗∗ 0.22 2.05(2.27) (3.98) (4.61) (2.87) (4.97) (5.89) (3.68) (6.74) (7.65)
SigmaConstant 35.07∗∗∗ 33.72∗∗∗ 33.75∗∗∗ 35.80∗∗∗ 34.22∗∗∗ 34.33∗∗∗ 33.71∗∗∗ 32.67∗∗∗ 32.50∗∗∗
(0.96) (0.92) (0.93) (1.23) (1.16) (1.18) (1.55) (1.50) (1.51)Observations 4650 4644 4581 3150 3148 3117 1500 1496 1464Log-Likelihood -5315.78 -5163.08 -5071.72 -3534.25 -3416.75 -3365.09 -1780.16 -1741.95 -1698.36χ2 31.21 278.22 283.58 27.60 210.96 214.35 4.89 69.62 76.89
Standard errors in parentheses∗ p < 0.05, ∗∗ p < 0.01, ∗∗∗ p < 0.001
Notes: The unit of observation is the voting decision made by an individual respondent. The table is split into three panels. Each panel workswith a different sample: all respondents (Full Sample), only those residing in areas affected by Florence (Florence), and only those affected by
Michael (Michael). Each panel reports all elements of β and σ. Sample sizes differ due to missing responses.
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Table A.3: Full Regression Results for Improvements in Precipitation Forecast
Full Sample Florence Michael
BetaOrder -5.09∗∗∗ -5.21∗∗∗ -5.26∗∗∗ -4.81∗∗∗ -4.85∗∗∗ -4.95∗∗∗ -5.71∗∗∗ -5.96∗∗∗ -5.75∗∗∗
(0.82) (0.81) (0.81) (1.00) (0.98) (0.99) (1.44) (1.43) (1.44)
Rate 0.27 0.44 0.63 0.04 0.00 0.11 0.75 1.27 1.43(0.81) (0.79) (0.80) (0.99) (0.96) (0.97) (1.41) (1.40) (1.41)
Income 0.06 0.06 0.06 0.07 0.03 0.01(0.03) (0.03) (0.04) (0.04) (0.06) (0.06)
Female 4.10∗∗ 3.68∗ 5.29∗∗ 4.73∗∗ 1.60 0.76(1.44) (1.48) (1.72) (1.77) (2.65) (2.74)
Experience 4.09∗ 4.09∗ 4.15∗ 3.99 5.90 5.86(1.84) (1.93) (2.10) (2.18) (4.07) (4.31)
Evacuated 4.22∗ 3.92∗ 3.38 2.78 5.61 5.83(1.74) (1.79) (2.10) (2.18) (3.09) (3.17)
Voice 4.25∗∗∗ 4.34∗∗∗ 5.07∗∗∗ 5.18∗∗∗ 2.74∗ 2.75∗
(0.70) (0.71) (0.87) (0.88) (1.18) (1.20)
Action 4.83∗∗∗ 4.70∗∗∗ 4.72∗∗∗ 4.51∗∗∗ 5.03∗∗∗ 4.84∗∗∗
(0.73) (0.74) (0.90) (0.92) (1.24) (1.24)
Long-term Risk 1.15 4.70 1.05 5.17 1.10 3.65Perception (1.99) (3.01) (2.31) (3.54) (4.07) (5.80)
Age -0.02 -0.05 0.06(0.04) (0.05) (0.08)
Owner -0.35 -0.73 0.67(1.45) (1.79) (2.50)
Tenure -0.00 0.00 -0.01(0.01) (0.01) (0.01)
Short-term risk -5.13 -6.97 -1.07Preception (3.54) (4.15) (6.79)
Hurricane Ins. -1.44∗ -1.15 -1.46Awareness (0.72) (0.89) (1.25)
FEMA 1.36 1.44 0.95Awareness (0.76) (0.92) (1.34)
NFIP 0.16 -0.59 1.74Awareness (0.69) (0.83) (1.21)
Damaged 1.03 2.79 -0.47(1.51) (1.99) (2.46)
Household 0.25 0.10 0.43Size (0.26) (0.43) (0.34)
Constant 39.31∗∗∗ 3.55 4.90 39.35∗∗∗ 1.45 5.33 39.24∗∗∗ 7.62 4.98(2.41) (4.22) (4.90) (2.96) (5.16) (6.14) (4.15) (7.50) (8.47)
SigmaConstant 37.38∗∗∗ 36.19∗∗∗ 36.21∗∗∗ 37.43∗∗∗ 36.02∗∗∗ 36.07∗∗∗ 37.24∗∗∗ 36.40∗∗∗ 36.22∗∗∗
(1.04) (1.01) (1.01) (1.28) (1.22) (1.23) (1.81) (1.77) (1.77)Observations 4650 4644 4581 3150 3148 3117 1500 1496 1464Log-Likelihood -5495.70 -5343.76 -5261.78 -3710.59 -3597.80 -3547.07 -1784.84 -1741.40 -1705.47χ2 38.63 265.24 272.82 23.27 197.87 204.69 15.80 72.66 79.58
Standard errors in parentheses+ p < 0.10, ∗ p < 0.05, ∗∗ p < 0.01, ∗∗∗ p < 0.001
Notes: The unit of observation is the voting decision made by an individual respondent. The table is split into three panels. Each panel workswith a different sample: all respondents (Full Sample), only those residing in areas affected by Florence (Florence), and only those affected by
Michael (Michael). Each panel reports all elements of β and σ. Sample sizes differ due to missing responses.
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B Survey Sample
In this section we provide examples of the survey questions used to elicit participants’ willing-ness to pay for proposed hurricane forecast improvements. We use the survey for HurricaneFlorence as demonstration; however, the process is exactly the same for Hurricane Michael.As described in the Survey Implementation section, the unique forecast-improvement com-binations are randomly generated for each participant. In addition, the order of forecastspresentation is randomized for each participant. Each of the following subsections representsone of the three forecast attributes that are used in the survey.
The valuation section is preceded with the following statement, “Please consider theadvisory referendum below. The expected cost to your household may seem high but considerthat hurricane research is costly, as it has to fund both human and physical capital. Whenconsidering how to vote, please bear in mind that there may be other things that you wouldrather spend your money on. Think about your monthly budget and how much, if anything,you are willing to pay before casting your vote. Click the box labeled “I vote Yes” if you arein favor of covering the proposed cost; otherwise, vote “I vote No” if you are against.”
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B.1 Track Forecast
This section describes the combinations for the track forecast attribute. Each participant isfirst provided with a description and image of the current track forecast:
“This image describes the progress in hurricane track forecast. Consider Hurricane Flo-rence. The dotted line describes what would have been the 72-hour predicted landfall regionif we had the same accuracy as in 2008. Over the last decade, forecasts have improved andreduced the track error by about 4.9% annually, and thus allowed us to narrow down thepotential landfall region to the solid line circle. The landfall regions are circles because ofprediction error: while we say the storm will be at a specific location in 72 hours (predictedlandfall), it is equally likely that the storm will be anywhere else in the circle.
Figure B.1: Hurricane Track Forecast
These improvements also mean that the time window for landfall for the 72-hour forecast,using Florence’s actual forward speed as a reference, went form 170 hours in 2008, to about103 hours in 2018. This is equivalent to an improvement of 40% in error reduction overten years.”
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Survey respondents are then presented with one of the three following rate improvementscenarios; status quo, 20% increase, or 20% decrease. The description of these changes is asfollows:
“Proposed changes are expected to reduce the error of track forecast even further. Thisrate of improvement would mean that the 72-hour predicted landfall for Florence, would looklike the figure:
Figure B.2: Hurricane Track Forecast Improvements
1) This level of progress means that the time window for landfall for the 72-hour forecast, us-ing Florence’s actual forward speed as a reference, would go from about 103 hours in 2018,to about [62 hours, 54 hours, 80 hours] in 2028. This is equivalent to an improvementof about [40%, 48%, 32%] in error reduction over the next ten years.
The proposed changes would provide a service to all the U.S. population susceptible to hur-ricanes, and it will increase the taxes your household currently pays. Knowing that it wouldcost your household an extra $(random bid value) each year in additional taxes, howwould you vote?”
The survey respondents answer yes/no to the first bid. Then depending on their re-sponse they are asked a follow up question that either increases or decreases the bid valueby 20%.
2) “If the changes instead cost your household an extra (1.2/0.8) * bid each year in addi-tional taxes, how would you vote?”
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B.2 Wind Speed Forecast
This section describes the combinations for the wind speed forecast attribute. Each partici-pant is first provided with a description and image of the current wind speed forecast:
“This image describes the progress in error reduction for hurricane wind speed forecastover the last decade for a 72-hour forecast. The X-axis represents how far into the futurethe forecast predicts wind speed, while the Y-axis shows the average error associated withthat prediction. The dotted line represents the accuracy in 2008, while the solid linerepresents the accuracy in 2018. Note that that errors increase because predictions fartherinto the future are less precise; in other words, they have larger errors. The closer the linesare to zero, the better the forecast.”
Figure B.3: Hurricane Wind Speed Forecast
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Survey respondents are then presented with one of the three following rate improvementscenarios; status quo, 20% increase, or 20% decrease. The description of these changes is asfollows:
“Proposed changes are expected to reduce the wind speed forecast error even further. Thisrate of improvement would mean that the 72-hour predicted wind speed would have the fol-lowing margins of error:
Figure B.4: Hurricane Wind Speed Forecast Improvements
1) This level of progress means that the error margin for the 72-hour forecast, using Florenceas a reference, would go from about +/- 13 mph in 2018, to about [+/- 9.5, +/- 8.7,+/- 10.4] in 2028. This is equivalent to an improvement of about [29%, 35%, 24%] inerror reduction over the next ten years.
The proposed changes would provide a service to all the U.S. population susceptible to hur-ricanes, and it will increase the taxes your household currently pays. Knowing that it wouldcost your household an extra $(random bid value) each year in additional taxes, howwould you vote?”
The survey respondents answer yes/no to the first bid. Then depending on their re-sponse they are asked a follow up question that either increases or decreases the bid valueby 20%.
2) “If the changes instead cost your household an extra (1.2/0.8) * bid each year in addi-tional taxes, how would you vote?”
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B.3 Rainfall Forecast
This section describes the combinations for the rainfall forecast attribute. Each participantis first provided with a description and image of current rainfall forecasts:
“This image describes the accuracy of a rainfall forecast. Consider Hurricane Florence.The shaded area describes the area susceptible to an underforecast by at least one inch ofrain. In other words, the area that could receive one inch or more of rain than what themodel would predict 72 hours before landfall. Over the last decade, forecasts have improvedand reduced the rain forecast error by about 4.9% annually, and thus allowed us to narrowdown the actual rain significantly. This is equivalent to an improvement of about 40% inerror reduction over ten years.”
Figure B.5: Hurricane Rainfall Forecast
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Survey respondents are then presented with one of the three following rate improvementscenarios; status quo, 20% increase, or 20% decrease. The description of these changes is asfollows:
“Proposed changes are expected to reduce the error in rain forecast even further. Thisimprovement would mean that the 72-hour area susceptible to underforecast for Florence,would look like the figure:”
Figure B.6: Hurricane Rainfall Forecast Improvements
1) “This level of progress means that the area receiving at least one inch of rain over whatwas expected, using Florence as a reference, would go from about 50,300 squared milesin 2018, to about [41,200, 38,100, 43,900 squared miles in 2028. This is equivalent toan improvement of about [18%, 25%, 12% in error reduction over the next ten years.
The proposed changes would provide a service to all the U.S. population susceptible to hur-ricanes, and it will increase the taxes your household currently pays. Knowing that it wouldcost your household an extra $(random bid value) each year in additional taxes, howwould you vote?”
The survey respondents answer yes/no to the first bid. Then depending on their re-sponse they are asked a follow up question that either increases or decreases the bid valueby 20%.
2) “If the changes instead cost your household an extra (1.2/0.8) * bid each year in addi-tional taxes, how would you vote?”
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