Last modified by Maptitude for Redistricting Support - 7 months ago
239 Views
2 min read

How can I create a theme that shows the predominant race/ethnicity in each feature?

Maptitude for Redistricting 2020 includes two new fields for each area layer with Public Law 94-171 data: Plurality and Plurality Label. The Plurality field contains a coded value that corresponds to the predominant race/ethnicity for the feature and its penetration. The Plurality Label field contains a multiple line label that lists the top three race/ethnicities and their percentages.

Race and ethnicity coding is shown in the following table:

Race/Ethnicity Code
Any Part American Indian I
Any Part Asian A
Any Part Black B
Any Part Hawaiian H
Any Part Hispanic L
White W

Percentage ranges are also coded according to this table:

Percentage Range Code
0%-30% 1
30%-50% 2
50%-70% 3
70%-90% 4
90%-100% 5

Using this coding, we can infer that feature with the code W4 has 70%-90% White population, while a feature with the code L3 has 50%-70% Any Part Hispanic population.

Maptitude for Redistricting 2020 also includes a Settings file with a color theme for plurality as well as a themes file that includes plurality for the Redistricting toolbox.

Using the Settings File

The settings file, Redistricting Settings.stg, can be found in the directory with the redistricting data for your state. This location is usually C:\XX 20YY Data Final, where XX is the state abbreviation and YY is the year.

  1. Open a redistricting map or plan in Maptitude for Redistricting.
  2. Right-click on the selection layer for which you want to apply a theme and choose Make working layer. **You should not use the Plurality theme for the Districts layer since Plurality is a special field that does not exist on the Districts layer.**
  3. Choose Map>Thematic Mapping>Color...
  4. Click Load.
  5. Choose the From Settings File radio button.
  6. Browse for Redistricting Settings.stg and click Open.
  7. Choose Plurality from the Name pick list and click OK.
  8. Click OK.
Maptitude for Redistricting applies the color theme to your map.

Using the Themes File

  1. Ensure that Maptitude for Redistricting is closed and copy rdthemes.bin from your redistricting data folder and paste to C:\Documents Caliper. **Note: This step only needs to be executed once.**
  2. Open Maptitude for Redsitricting.
  3. Open a plan.
  4. The precalculated themes can be selected from the Theme dropdown in the Redistricting Toolbox.