Data Display and Cartography Chapter 8 – Chang Week 5
Map Elements Title Body – most important Legend North Arrow Scale Acknowledgement Neatline/Map border Others (options): Projection, grids, insert, data quality information.
Exercise Add the following elements to your county map –Title –Legend –Scale Bar –Acknowledgement –North Arrow –Neatline/Border
Map Symbols Points Lines Polygons Exercise – Open your ArcMap/ArcView project with your county census tract polygons. Add GPS points to the map. Download Street file from TIGER website ( –select TN –Select County name, then click Submit Selection –Select Line Features – Road and click Proceed to Download. –Click Download File –You should get a zipped file starting with lkA47xxx.zip. Start unzipping this file to get your road layer (again, it contains three files for a shape) –Move these three files to your folder (you’d better have a folder named “Data” under your personal folder) Add this road layer to your county map
Size, Color and Patterns Adjust size of point symbols (grouped, not individually for the event points data) D-C on tgr47141trt00 (in ArcMap) to bring up the “Layer Properties” window. Select Unique Values under Categories and click “Add All Values” button from the window. You will have to choose a Value Field, such as tgr47000demtrt.P This will you the choices of individual colors for each polygons.
Color Hue – colors – wavelength Value – lightness/darkness of a color, black to white. Usually, darker colors are more important features. Chroma (saturation) – richness/brilliance of a color. A fully saturated color is pure, whereas a low saturation approaches gray. Rules : Hue is for qualitative data. Chroma and Value are for quantitative data. Quantitative mapping received much more attention than qualitative mapping
Color Schemes Single Hue Scheme – varies value and chroma to show sequential order Hue and Value – from light value of one hue to a darker value of a different hue. Examples are yellow to dark blue (or dark red). Better for recognition of general map information Diverging or double-ended scheme: use graduated colors betw two dominant colors, eg from dark blue-> light blue->light red -> dark red. Good for negative - > positive values, and other maps too. Part Spectral Scheme – use adjacent colors of the visible spectrum to show variations in magnitude, such as from Yellow to Orange to Red, Y – G – B. Full Spectral Scheme – use all colors in the visible spectrum. Used in elevation, not recommended for other maps (no logical sequences)
Types of Maps – Thematic Maps Dot Map (your GPS points) Choropleth Map (population in each tract) Graduated Symbols (based on field values) Pie Chart map Flow Map Isarithmic map (contour) Dasymetric map
Typography Serif (with serif), Sans Serif (without serif)- serifs are small, finishing touches at the ends of line strokes, which tend to make it easier to read running text in newspapers and books. Sans Serif : good for maps with complex map symbols and remain legible even in small sizes Type weight (bold/regular/light), Type width, font, size (in points),
Labeling Examples: use USA + City Identify maps with 1) confusing legend 2) too many boxes or other typographic errors in Internet.