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The public’s risk perception of technology

• NCSU Workshop on• Communicating Health and Safety Risks on• Emerging Technologies in the 21st Century

• McKimmon Center, North Carolina State University• Raleigh, NC August 28-29, 2008

Professor Lennart SjöbergCenter for Risk Research

Stockholm School of EconomicsSweden

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Outline• The Psychometric Model of risk perception

• Trust

• Risk targets

• Demand for risk mitigation

• Affect (attitude) and emotions

• Experts and the public

• Social validation

• The attitude towards nanotechnology

• Conclusions

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Why research on risk perception?

• Risk is a very common issue in policy deliberations

• This is true both for decision makers, experts and the public

• Several risk related issues have created great economic and political turbulence

• There is therefore a need to know more about how people perceive and react to risks

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Traditional view of risk perception (the Psychometric Paradigm)

• There are only a few generally applicable factors which determine perceived risk.

• ‘Novelty’ and ‘dread’ are the major factors with regard to a hazard

• Demand for risk mitigation is governed by the size of the risk – greater risk leads to increased demand

• Experts are ‘objective’ and not influenced by ‘subjective’ risk factors such as ‘novelty’ and ‘dread’

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Traditional view of risk perception (continued)

• Trust in experts and institutions is very important. If it can established, trust will reassure the public and make them believe in and accept the experts' ‘objective’ risk assessment

• The social dilemma of risk management concerns different views of experts and the public – hence research is concentrated on these two groups

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The ‘classical’ illustration of the Psychometric Model

Voluntary, immediate, known, controllable, old

Involuntary, delayed, unknown, uncontrollable, new

Not certain to be fatal, common, chronic

Certain to be fatal, dread, catastropic

Food colouringFood preservatives

Spray cans

AntibioticsContraceptives X-rays

Vaccination

Nuclearpower

Pesticides

Commercialaviation

Surgery

Motor vehiclesConstruction

Smoking

General aviation

HandgunsMotorcycles

Police workFire fighting

HuntingSwimming

Mountain climbing

RailroadsElectric power

Home appliancesFootball

Power mowers

Skiing

AlcoholicbeveragesBicycles

2.00

1.50

1.00

0.50

-0.50

-1.00

0.50 1.00-1.00 -0.50

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Are ‘dread’ and ‘novelty’ really driving factors behind risk perception?

• Explained variance between individuals of original model is typically only 20%, often less

• This is mostly due to the ‘dread’ factor

• ‘Novelty’ has no or very little explanatory power at all, with regard to individual differences

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What is ”dread”?

• The word suggests that the factor is a measure of an emotional reaction

• Many people writing about it seem to have interpreted it that way

• However, all items in the ”dread” factor, with one exception, do not measure emotional reactions but severity of consequences

• When ”dread” is related to pereived risk, it is due to these items, not the singular emotion item

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Factors needed to improve models of risk perception

• ‘Interfering with nature’ is a very important additional factor

• Social trust is important, but epistemic trust, trust in Science, is even more so

• Reactions to new technology are not driven by ‘novelty’ per se but by other factors, such as perceived benefit, or whether the technology brings about unique advantages and is hard to replace

• Attitude or ”affect” plays an important role

• Risk sensitivity is an aspect of individual differences which is quite important – some people rate risks as large, others rate them as small

• In addition, various hazards, some new (such as terrorism), require their own specific factors

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Factors beyond social trust

• Typically social trust (in experts or organisations) has only a weak effect on perceived risk – correlations of 0.3 or less

• Trust in science, as distinct from social trust, has a stronger effect – epistemic trust

• Another important factor is perceived antagonism

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Effect of social trust is mediated byepistemic trust (model of nuclear waste risk)

Perceivedrisk

Epistemictrust

Risksensitivity

Socialtrust

Antagonism

R2=0.56R2=0.37

GFI=0.95, AGFI=0.93, RMSEA=0.030

-0.23

0.28

-0.50

0.12

-0.19

0.38 -0.510.35

-0.22R2=0.41

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Conclusion about trust

• Epistemic trust seems to be more important than social trust

• The effect of social trust is mediated by epistemic trust

• In other words: trust in people and institutions is important to the extent that it promotes belief in the substance of their message

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Risk target: Whose ‘risk’ – more specifically?

• Personal and general risk differ both as to level and rank order

• General risk is important for lifestyle (smoking etc.,)

• Personal for environmental risks, and technology hazards

• Research shows that such risk ratings with a non-specified target are close to general risk

• But, general risk is not the most relevant in policy contexts

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Plot of mean general vs. mean personal risk, data from the public.

Mean personal risk

0 1 2 3 4 5 6

Mea

n ge

nera

l ris

k

0

1

2

3

4

5

6

y = x

Regression line

General risks rated as much larger thanpersonal risks

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Different dynamics of personal and general risk

• General risk is related to policy for hazards perceived to be under one’s personal control

• Personal risk is related to policy for hazards not under one’s personal control

• Examples: alcohol and nuclear power

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Focus on risk – traditional approach

• People are asked to rate the ‘risk’

• It is assumed that perceived risk, as defined in this way, is the factor driving risk-related behaviour – such as demand for risk reduction

• But the assumption is usually implicit

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Risk mitigation – the problem

• What drives demand for risk reduction?

• Is perceived risk the important factor?

• If not, what factor is most important ?

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Example

• Consider the risk for a Swedish citizen, age 30–45, to1. get a severe cold during the next 12 months

2. become infected with the HIV virus during the same time period

• Which risk is the largest?

• From which risk is it more important to be protected?

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Risk perception studies show that

• Risk and probability are closely related

• Severity and demand for risk reduction are closely related

• Risk and demand for risk reduction are only moderately related (“probability neglect”)

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Implications

• In risk communication it should be clear that the public wants to hear about severity of consequences, not so much about probabilities:

• Probability is hard to understand• Precise estimates of very small probabilities must rely on

many assumptions and are seldom very credible

• In risk perception research, it is necessary to broaden the scope – just studying ‘risk’ is not sufficient

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Emotions and affect

• “Affect” is a word with several distinct meanings: emotions or values (attitudes)

• It is necessary to clarify which one is investigated – they are psychologically quite different

• Both are related to risk perception

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Attitude (affect), trust, risk sensitivity

and attitude towards nuclear power (1991 study)

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Emotions – study of emotional reactions to a nuclear waste repository

• Several emotions were rated, not only one

• Negative and positive emotions were rated

• About 800 respondents from two communities where site studies are now carried out

• Two candidate municipalities, one control and a national sample

• Response rate 50%

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Model of the attitude to a nuclear waste repository

Attitude to the

repository

Risk to the municipality

Epistemic trust

Negative emotions

Positive emotions

Socialtrust

Attitude to nuclear power

- 0.21

0.26

0.06 0.13

- 0.160.18

Model of attitude to the repository explaining 65% of the variance

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-0.12-0.61Worry

0.04-0.29Shame

0.03-0.25Guilt

0.210.57Satisfaction

-0.12-0.58Sadness

0.170.28Interest

-0.06-0.65Fear

-0.10-0.55Contempt

-0.08-0.62Anger

The anticipated emotional reaction of others to nuclear

power

Own emotional reaction to nuclear power

Emotion

Correlations between emotional reactions and the attitude to nuclear power

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Mean emotional reactions attributed to others versus own reactions

Own emotional reaction

Oth

ers’

em

oti

on

al r

eact

ion

1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.2 3.43.0

1.5

3.5

3.0

2.5

2.0

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A methodological point

• Instructions to rate “dread” do not specify WHOSE dread

• This probably leads to the interpretation to rate the emotional reactions of OTHERS

• In turn, data therefore reflect only a weak link between emotional reactions and perceived risk

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Conclusions about emotions

• Specific and current emotional reactions do seem to explain much of attitudes and policy behaviour, attitude (affect) somewhat less

• Compare these strong effects with the almost zero importance of anticipated ‘dread’ of others

• Both positive and negative emotions are important

• Note that ‘worry’ contributes beyond the effect of ‘fear’

• Anger seems to be more important than fear in policy contexts

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Experts versus the public

• Original work claimed that experts make ‘correct’ and ‘objective’ risk judgements used a very small group of ‘experts’ with questionable competence

• Later work with substantive experts has shown that they have similar structure of risk perception, but lower level

• Risk perception is related to experts’ field of responsibility – not to knowledge

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Personal risk of genetically modified food, experts and public

0 1 2 3 4 5 6 7

Pe

rce

nt

of

resp

on

de

nts

0

10

20

30

40

50

ExpertsPublic

No risk Very large risk

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Over-all attitude to the use and development of genetically modified food

Response category

0 1 2 3 4 5 6 7 8

Per

cen

t of r

esp

ond

ent

s

0

10

20

30

40

50

Experts Public

Use and develop Phase out, prohibit

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Experts and the public – personal and general food risks

Fat foods Cooking Bacteria Additives Pesticides Env.toxins

Me

an

ris

k ra

ting

0

1

2

3

4

Public, personal risk Experts, personal risk

Fat foods Cooking Bacteria Additives Pesticides Env.toxins

0

1

2

3

4

Public, general riskExperts, general risk

Personal risk General risk

34-1.0 -0.5 0.0 0.5 1.0 1.5 2.0

Serious traffic accident

Inadequate medical care

Unsound diet

Smoking

Alcohol consumption

Radon - lung cancer

Inadequate food

Vehicle exhausts

Inadequate housing

Hit by lightning

Unemployment

Industrial pollution

Background radiation

Ozon layer

Climate change

Swedish nuclear power

Nuclear waste in transport

High-level nuclear waste

Waste disposal facility

Foreign nuclear power

Public - expertsPublic - engineers

Experts>public Public>experts

Difference Public - experts or engineers

Note

“Rhetorical contrast”

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1 2 3 4 5

Mea

n r

atin

gs

by

mal

e ex

per

ts

0

1

2

3

4

5

Mean ratings by men, members of the public

A

1 2 3 4 5 6M

ean

rat

ing

s b

y fe

mal

e ex

per

ts

0

1

2

3

4

5

Mean ratings by women, members of the public

B

Ratings of risk dimensions of nuclear waste

by the public, and male and female experts

Expert-public difference for both genders

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0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0

Mea

n r

atin

gs

by

mal

e ex

per

ts

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

Mean ratings by female experts

No gender

difference

among experts

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-0.1 0.0 0.1 0.2 0.3 0.4

Reg

ress

ion

co

effi

cien

ts,

eng

inee

rs-0.1

0.0

0.1

0.2

0.3

0.4

Regression coefficients, public

B

0.0 0.1 0.2 0.3 0.4

Reg

ress

ion

co

effi

cien

t, e

xper

ts

-0.1

0.0

0.1

0.2

0.3

0.4

Regression coefficient, public

A

Regression coefficients in model of perceived nuclear waste risk, results from analyzing data from experts (A) and engineers (B) plotted against results from analyzing data from the public.

Very similar models for experts and the public

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Correlations between risk perception ratings and the psychometric factors (genetically modified food) for the public and experts

-0.30-0.52-0.42-0.38Social trust (Likert items)

-0.08-0.27-0.31-0.24Epistemological trust

0.080.470.540.50Severity of consequences

0.380.610.560.51Immoral risk

0.080.470.530.47Interfering with nature

-0.060.310.510.44New risk

0.010.190.430.40Dread

ExpertsPublicExpertsPublicExplanatory variable

General riskPersonal risk

Experts’ risk ratings unrelated to “subjective factors,

But only for Dread and Novelty and for general risk

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Conclusion – public and experts

• Experts judge personal risk in a manner similar to the public

• However, their judgements of general risk seem to be less correlated with the ‘subjective’ factors

• Other studies have shown that personal risk is most important in policy related to technology and the environment

• Experts judge risks to be smaller when they are within their general area of responsibility

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Why do group differences arise?

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Frequency of interaction about the issue of nuclear power

NeverSeldom

Not very often

Rather oftenVery often

Mea

n at

titud

e t

o nu

cle

ar p

owe

r

-2.0

-1.5

-1.0

-0.5

0.0

0.5

1.0

Friends negativeFriends positiveFriends divided

The importance of social interaction and social validation

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Could social validation explain part of the gender differences in attitude?

• 32% of the male respondents talked mostly to other men about nuclear power (NP), 10% women did so

• 2% of the male respondents talked mostly to women about NP, 12% of the women did so

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Those who talked mostly with men

were more positive towards

nuclear power

Who did you mostly talk with about nuclear power?

Mostly w

ith m

en

Equally ofte

n with

both m

en and women

Mostly w

ith w

omen

Att

itude

to

war

ds

nucl

ear

po

wer

-0.4

-0.3

-0.2

-0.1

0.0

0.1

0.2

0.3

MenWomen

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Conclusion about social validation

• Strong effects can be seen, people use the beliefs of friends and colleagues as a source of validation

• This factor tends to make vocational, geographical and gender based groups diverge

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What does our research imply for risk communication?• Emotions are important to take into account

• but not only strong fear

• Concern about ‘Interfering with Nature’ is a major factor• but not novelty of a risk

• People’s understanding and trust in science is very important• social trust is less important

• ‘Risk’ and ‘probability’ are marginal to people• they respond to notions about anticipated consequences and

whether a technology has unique advantages

• Experts are not that different from the public in how they react to hazards outside their field of responsibility

• Social validation is a promising theme for future research

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The attitude towards nanotechnology

• Nationally representative data, N=934, response rate 54%, postal survey

• Data were corrected in the beginning of 2008

• 20 technologies rated as to acceptability (use much more – much less or not at all)

• Nanotechnology defined: “technology which works in an extremely small scale (atoms, molecules)”

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Approval ratings of 20 technologies

Mean approval rating

1 2 3 4 5 6 7

Pesticides

Genetically modified food

Computer games

Commercail aviation

Private automobiles

TV

Person identification number

Microwave ovens

Cellullar telephones

Blood pressure medicine

X-ray investigations

Car ferries

E-mail

Nuclear power

Automobile satelllite navigavtion

Internet

Nanotechnology

Heart transplants

High speed trains

Wind power

MenWomen

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Acceptance of nanotechnology and level of education

Grammar sch

ool

Vocatio

nal training

High school 2

years

High school >

2years

College

Graduate school

Me

an a

ppro

val r

atin

g of

nan

otec

hno

logy

2.5

3.0

3.5

4.0

4.5

5.0

5.5

Use more

Use less

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Acceptance of nanotechnology and age

Age

18-24 25-34 35-44 45-54 55-64 65-74

Mea

n ap

prov

al r

atin

g of

nan

otec

hnol

ogy

4.0

4.2

4.4

4.6

4.8

5.0

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Correlations between values and attitude towards nanotechnology

-0.123Cultural theory: Egalitarian attitude

0.100Cultural theory: Hierarchical attitude

0.100Cultural theory: Individualism

-0.117Schwartz: discipline

0.047Schwartz: prosocial behavior

0.169Schwartz: achievement

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Factor analysis of the 20 acceptability ratings

gave 2 dominating factors

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Conclusions about the attitude towards nanotechnology

• The evaluation was positive – but so far we had relatively little public debate about nanotechnology

• Women were less positive towards nanotechnology than were men – this is not true of all technologies

• People with a high level of education were more positive, older people more negative

• Nanotechnology was included in a cluster och new and advanced technologies

• The nanotechnology attitude was unrelated to basic values

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Risk and nanotechnology: further work

• probabilities vs consequences

• social vs epistemic trust

• Interfering with Nature

• the role of affect, attitudes and emotions

• specific aspects not found for other hazards

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For more information…

• See my homepage

http://www.dynam-it.com/lennart/

• Several papers and reports can be downloaded from that site

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Thank you for your attention!

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