Maps, Cartography, and Presenting Data Class 6 GISG 110

Objectives Maps and Cartography Map and design objectives Factors controlling the design process Communication in maps Types of map outputs (formal, working) Types of maps (reference, thematic) Composition Issues in cartographic design and solutions Multivariate mapping and map series Presenting Data Creating maps in ArcMap Printing and plotting maps

Maps and Cartography - not the same Output from GIS Cartography The art, science, and techniques of making maps

Map and design objectives Map objectives Share information Highlight relationship Illustrate analysis results Communicate effectively, efficiently, clearly Design objectives Manipulate the graphic characteristics Fulfill the intended purpose

Factors controlling design process Purpose: Objective, what is being mapped Reality: Orientation (east-west map, landscape) Available Data: Raster or vector Map scale: Controls how many data can appear, symbol size and overlap Audience: Summary information or details, bigger symbols for people farther away? Conditions of use: Outside, inside, close up, far? Technical limits: Medium – digital or hardcopy All contribute to final design

Communication in maps Successful communication in maps involves the relationship between Cartographer/GIS Specialist Map Map user Mental image of reality (no two are alike)

Communication in maps Cartographer/GIS specialist Compiles data from several sources Selects only data necessary to fulfill map objective Takes selected data, classifies into fewer categories, simplifies it, and selects proper symbology for displaying information on the map

Communication in maps Map user Takes map, reads symbology, analyzes relationships, and interprets information depicted Through conclusion or inference Acquire mental image of area that they may not have seen before Conclusions or inferences based solely on symbology presented in map

Communication in maps The communication channel Cartographer and user will never see the exact same mental images Up to cartographer to come as close as possible to the users mental image when portraying data Ask right questions to make communication easier and produce better maps

Communication in maps Making a good map What is the motive, intent, or goal of the map? Who will read the map? Where will the map be used? What data is available for the composition of the map? What resources are available in terms of both time and equipment? Answers will control the design process (and determine cost)

Types of outputs Formal Presentation level map, intended for distribution or publication Should possess good map composition Working Possibly missing map elements Used for markup and editing Not intended for distribution Should be stamped with “DRAFT”

Types of maps General or Reference Show locational or positional types of data Variety of features and used by many disciplines Thematic Show specific geographic themes Choropleths and isopleths Qualitative and quantitative

Choropleth and isopleth maps Constructed from values describing properties of non-overlapping areas (e.g., census tracts) Isopleth map Used to visualize phenomena that area conceptualized as fields, and measure on interval or ratio scales (e.g., precipitation)

Choropleth and isopleth maps Death rate by Health Service Area Total precipitation for 1996

Thematic maps - Qualitative Depict data such as different soil types and other features with equal important at a nominal scale

Qualitative maps Displays qualitative values as features or categories Where something is or isn’t Patterns and trends Features Categories

Thematic maps - Quantitative Show differences in quantitative characteristics Using interval or ratio scale to show population or variation in temperature or humidity

Quantitative maps Display quantitative values as quantities or charts When you want to show how much Measures: count, ratio, rank Quantities (e.g., graduated symbols) Charts

Classifying quantitative values review Equal interval Natural breaks Quantile Standard deviation

Thematic maps Qualitative and Quantitative Both show distribution of an attribute, and (generally) depict a single attribute or relationship

Hardcopy and digital maps Paper map Digital map Fixed scale Zoom allows maps to be viewed at range of scales Fixed extent Seamless medium for viewing space, pan to new areas Static view of the world GIS animation Flat and limited in perspectives 3-D visualization with interactive pan and zoom View of world essentially complete Data layers turned on and off to examine data combinations Single, map producer-centric, view of world Create own, user-centric map in interactive way

Map composition Creating maps with interrelated elements and good visual balance Map body Inset/overview map Title Legend (or table of contents) Scale Direction indicator (north arrow) Map metadata (sources, date, author)

Issues in cartographic design Colors, shade patterns, and text Perception of colors and symbols Eyes have limitations (stop at twelve colors and 7-8 shades) Legibility of features and text Smallest symbol that can be read at certain distance Visual contrast and hierarchy Variation in size or graytone value Helps reader to focus on important areas first Visual balance Careful of symbols and visual weight

Range of visual resources Attribute mapping Cartographers reduce world to points, lines, areas Bertin’s The Semiology of Graphics (1983), inventories resources using the categories of size, shape, value, texture or pattern, hue, orientation, and shape

Use of visual resources Each resource can be used Individually to draw attention to map features Simultaneously to Stress important information Improve legibility

Effective map making As you develop a design for a map, think carefully about every element Does it play an essential function? Could it be simplified? Does it require elaboration? Is it of critical importance to reader comprehension, or only of background interest? Everything that appears on a map should be there for a defensible reason relating to message and audience

Less is more Consider ways to simplify your design and make it more legible Too much detail or too complex a layout can confuse readers Do not avoid experiments, but test them carefully with potential readers

Concepts Multivariate mapping Map series

Multivariate Mapping Show two or more variables for comparative purposes E.g., rainfall and malaria risk Requires experienced and/or artistic cartographer/GIS Specialist Can be difficult to show

Map series and templates Collections of similar maps (e.g., atlas) Costly, inefficient to change Map templates are cost effective Atlas, map series, or map books require considerable financial and human resource investments to create and maintain Templates can be manual or automated to produce Contain same map elements and layer symbology Share projection and general layout

Map limitations Maps can lie accidentally or on purpose E.g., Incorrect use of symbols convey wrong message by highlighting one feature at expense of other Single realization of a spatial process E.g., A map of soil textures is derived by interpolating soil sample texture measurements. Repeated sampling shows natural variation in texture measurements (not a single map) Often created using complex rules, symbology, conventions Difficult to understand and interpret by untrained viewer Multivariate thematic mapping where classification schemes and color symbology difficult to comprehend

Review – Maps and Cartography Name five factors that control cartographic design. General or _____ maps show location or positional types of data. Both quantitative and qualitative thematic maps show distribution of an attribute, and (generally) depict a _____ attribute or relationship. Quantitative thematic maps depict data with equal importance at a nominal scale. (T/F) Human eyes have limitations, which stop at _____ colors and _____ shades. Legibility of features and text refers to the smallest symbol that can be read at certain distance. (T/F) Multivariate mapping shows _____ variables for comparative purposes. In Bertins book, The Semiology of Graphics, what does semiology mean? Maps can lie accidentally or on purpose. How? Mapping is the art, science, and techniques of making maps (T/F). Name five factors that control cartographic design. PURPOSE, REALITY, AVAILABLE DATA, MAP SCALE, AUDIENCE, CONDITIONS OF USE, TECHNICAL LIMITS Both quantitative and qualitative thematic maps show distribution of an attribute, and (generally) depict a _____ attribute or relationship. SINGLE General or _____ maps show location or positional types of data. REFERENCE Quantitative thematic maps depict data with equal importance at a nominal scale. (T/F) False – Qualitative Human eyes have limitations, which stop at _____ colors and _____ shades. Twelve, and 7-8 Legibility of features and text refers to the smallest symbol that can be read at certain distance. (T/F) True Multivariate mapping shows _____ variables for comparative purposes. TWO or MORE In Bertins book, The Semiology of Graphics, what does semiology mean? Study of signs? Symbology? Simplifying? Sorting? Maps can lie accidentally or on purpose. How? Incorrect use of symbols convey wrong message by highlighting one feature at expense of other Mapping is the art, science, and techniques of making maps (T/F). False - Cartography

Presenting Data

Objectives Presenting Data Creating maps in ArcMap Printing and plotting maps

Creating maps in ArcMap Design in Layout view Data frames organize layers Map elements are added to a virtual page Maps stored as MXD files Data location Layer properties

Setting up the page Remember the purpose Will the map be viewed up close or at a distance? What is the best page size? Landscape or portrait? What printer will be used? What are printer size limitations? File  Page and Print Setup

Inserting map elements Map body Title Legend North arrow Scale bar Other text

Legend Properties dialog Five windows to set up Legend 1 2 3 4 5

Adding a north arrow and scale bar Graphical scale bar Fractional scale Verbal scale bar Change unit, increments, color, font Change angle, size, color

Inserting textual information Text box prompt Title Data source, date, projection Date of map and data Disclosures and acknowledgments Author Double-click text

Layout tools Zoom and pan the layout page Zoom is different than Data view Zoom tool Scale remains same in Layout view Additional layout settings from Tools  Options Add charts and reports

Grids and rulers Determine the size of map elements Use guides to arrange elements Use grids to position elements at specific points Use snapping for precision and efficiency

Creating and using map templates Gives all maps in a series the same look ArcMap templates (show how to create and access) Create your own File  Save As

Printing and plotting maps File  Print Choose a Printer Engine (ArcPress, PostScript, Windows)

Review – Presenting Data Maps are designed in the ______ view. How do the zoom tools on the Layout toolbar differ from those on the Data view Tools toolbar? Why would you create or use a map template? What map elements can be added to a map layout? Map templates gives all maps in a series a unique look. (T/F) Maps are designed in the ______ view. LAYOUT How do the zoom tools on the Layout toolbar differ from those on the Data view Tools toolbar? SCALE REMAINS SAME IN LAYOUT VIEW Why would you create or use a map template? GIVES ALL MAPS IN A SERIES A UNIFORM LOOK What map elements can be added to a map layout? TITLE, MAP BODY, LEGEND, NORTH ARROW, SCALE BAR, OTHER TEXT Map templates gives all maps in a series a unique look. (T/F) False – same look

Remainder of Class Break SANDAG publications/writing about maps Quick Demonstration: Inserting maps and graphics in PowerPoint Lab: ESRI Chapter 18 Making maps from templates ESRI Chapter 19 Making maps for presentation