presented by:

Tim HaithcoatUniversity of Missouri

Columbia

with materials of:Dennis Fizsimons, SW Texas State University

George McCleary, Jr., University of Kansas

DesigningBetter Maps

2

Design is a ChoiceDesign is a Choice

The theory of the visual display ofquantitative information consists ofprinciples that generate design optionsand that guide choices among options.

The principles should not be appliedrigidly or in a peevish spirit; they are notlogically or mathematically certain; and itis better to violate any principle than toplace graceless or inelegant marks onpaper.

3

Design is a ChoiceDesign is a Choice

Most principles of design shouldbe greeted with some skepticism,for work authority can dominateour vision, and we may come tosee only through the lens of wordauthority rather than with our owneyes.

4

Design is a ChoiceDesign is a Choice

What is to be sought in designs for thedisplay of information is the clearportrayal of complexity.

Not the complication of the simple, ratherthe task of the designer is to give visualaccess to the subtle and the difficult --that is, the revelation of the complex.

5

GeneralizationGeneralizationSelection

Classification

Simplification

Exaggeration

Symbolization

Induction

ClassificationClassification

Unclassed Classed

SimplificationSimplification

less more

ExaggerationExaggeration

less more

SymbolizationSymbolization

Abstract Representational

InductionInduction

Positive Negative

.

. . .

.

. . .

after: Jacques Bertin. Graphics and Graphic Information Processing. New York: Walter de Gruyter, 1981.

Shape

Visual VariablesSp

atia

l Dim

ensi

on

Point0-D

Line1-D

Area2-D or

more

Direction

Textureor

Pattern

Coloror

Hue Size Value

R

G

Y

Y

Y

Y

R

G

GR

Qualitative Quantitative

Visual Variables TypographyVisual Variables Typography

Size

Value

Direction

Texture

Form

Color

Foreground

Background

Modified from: Borden Dent, Cartography - Thematic Map Design, 3rd ed. p. 264.

IncreasingVisual

Hierarchy

Scale/Scale/ResolutionResolution

200% 150% 100% 75% 50%

15

Map Type & Symbolization Map Type & Symbolization (1 of 3)(1 of 3)

Symbol

Point

Point

Characteristics

flow of distribution & relative spatialdensity (high/medium/ low relativedensity)

“interval” construction - “ordinal” reading

Related & limiting variables used inconstruction

Specific point or areal unit -- actuallocation, centroid or weighted center

Good for:

– high/low values in close proximity

– Symbolizing totals

– Aggregate data for several locations orareas

Map Type

Dot Map

Graduated

Symbols

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Map Type & Symbolization Map Type & Symbolization (2 of 3)(2 of 3)

Symbol

Line

Line/

Surface

Volume

Characteristics

Width of line represents data along route

Segmented or uniform

Isometric - points/isoplethic - areas

Form of distribution & gradients mostimportant

Distribution treated as surface of a volume

Surface “contours” - ridges, troughs, peaks,etc. - arrangement or direction of magnitudes

Commensurable - data values can be derived

Planimetric - correct horizontal position(within accuracy limits of map)

For continuous data only

Map Type

Flow/

Network

Isarithmic

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Map Type & Symbolization Map Type & Symbolization (3 of 3)(3 of 3)

Symbol

Area

Area

Characteristics

Data by areal units - “enumeration units”

Relative location most important

Totals seldom mapped; usually derivedvalues or “averages” (mean, median, mode)

Ratios/densities - account for area

Ratios, percentages, proportions -eliminate area

For discontinuous data only (or datatreated as such)

Data by areal units

Continuous (connected) or discontinuous(separated)

Data scaled proportionately as unit’s area

Map Type

Choropleth

Cartogram

CommonCommonQuantitativeQuantitativeMap TypesMap Types

Choropleth Isoline

Dot Map GraduatedSymbol

Nominal

Ordinal

Interval

Ratio

Mea

sure

men

t Lev

elSpatial Dimension

Post Office

Church

Airport

Point0-Dimension

Line1-Dimension

Area2-Dimensions or more

City

Town

Village

1000

500

200

Population

10 - 15

5 - 9.9

.1 - 4.9

% Unemployed

Continental Divide

Railroad

Highway

Trail

Highway

Interstate

2 Lanes

4 Lanes

6 Lanes

1000

500

100

Vehicles (per hour)

BrownJonesSmithWilson

HighMediumLowVery Low

1945194719501954

>400200-40050-199<50

Persons perSquare mile

Ownership

Crop Yield

Date of Annexation

Population Density

23

The Map Design Process:The Map Design Process:

PlanningPlanningWhat information do you need to convey?Is a map the best way to communicate thisinformation?What problem or question needs to be addressed?What information needs to be included?Is data readily available?Who is the audience?Is there a given style for this type of map?Will the map be part of a series?Sketch out several layout designsReality: money, materials, equipment, labor, & timeHow will I proceed?

24

The Map Decision Triangle

Time

Quality

Cost

25

The Map Design Process:The Map Design Process:

ComposingComposingWhat map elements need to be visually dominant?What will be the final size of the map?How will the map be reproduced?Does the title or caption clearly identify the mappurpose?Does each map element directly contribute to yourpurpose?Are sufficient base data present to support thespatial distribution?Do I need to define any map elements in a legend?Does the map communicate pattern(s)?Is the map too complex? Too Simple?

26

The Map Design Process:The Map Design Process:

Editing & Proofreading Editing & Proofreading (1 of 2)(1 of 2)

Has the quality of the data been overstated?

Have sources of statistical or “borrowed” databeen cited?

Are there any typographic, grammar, or spellingerrors?

Are there any geographical errors?

Is the map legible and readable?

Has anything been omitted?

Have I communicated the information? How do Iknow?

27

The Map Design Process:The Map Design Process:

Editing & Proofreading Editing & Proofreading (2 of 2)(2 of 2)

Does the visual hierarchy reflect levels ofimportance?

Do all of the map elements work as a whole?

Can anything be omitted?

Am I willing to let this map stand as a measureof my ability and accomplishment?

28

Map Critique Checklist Map Critique Checklist (1 of 2)(1 of 2)

The overall look ofthe mapSubjective, oremotional, reactionsto the map(authoritativeness,pleasingness,…)Content of the mapPotential usesAppropriateness of amap for the purposeProjection

Accuracy, precisionGeneral mappingmethodPoint symbolsLine symbolsColor - aesthetics,suitability forrepresenting contentOther area symbolsType style, size,placementDetails

29

Map Critique Checklist Map Critique Checklist (2 of 2)(2 of 2)

Suitability for theaudienceExecution & printingqualityLayoutScale of mapClarity of scaleindicators - literal &graphicLegend clarityTitle clarity &adequacy

Quality of the paperMap size, format,foldingContext of the map(series, individual;accompanied or notby text,…)Use of the map inpractice (e.g. roadmap/street map cannot be“tested” strictly in anarmchair)

Overall effectiveness

30

Factors Affecting Factors Affecting Choropleth Choropleth MapsMaps

Data quality– Appropriate size, shape & number of

enumeration units– Scale of resolution– Availability -- alternatives (surrogate

variables)– Data preprocessing -- rate, ratio, or percentage

(derived values)

Number of classes– Classed or unclassed– 2,3,4,5,6,7,8,9 or n classes

31

Factors AffectingFactors Affecting Choropleth Choropleth Maps Maps(continued)(continued)

Method of Classification– Subjective/natural breaks

– Optimization, standard deviation, equalintervals, quantiles, etc..

Legend Design– Actual values, rounded values, continuous

range values

32

Factors AffectingFactors Affecting Choropleth Choropleth Maps Maps(continued)(continued)

Symbolization– Value shadings:

• Graded sequence - percentage (100% black - 0% white)

• Graded sequence (no 100% or 0%)

• Graded sequence which reflects actual data values(class means)

– Color/hue: natural versus arbitrary– Value shading of a hue or multiple hues

Texture of value shadings:– Resolution - fine to course– Dots versus lines