Working with custom variables

The District Statistics dialog box displays demographic information per each district, precinct, or territory in your plan. Esri Redistricting Online comes with out-of-the-box statistics that are commonly used by the redistricting community.

With Esri Redistricting Online, you can create custom variables that calculate statistics relevant to your task. You can also save, load, edit, and delete the custom variables depending on your business needs.

The following topics are explained in detail:

• Creating a custom variable
• Saving a custom variable to file
• Editing a custom variable
• Loading a custom variable
• Deleting a custom variable

Note:

The custom variables use demographic values taken from the U.S. Census data. For more information on demographic values, see Understanding demographic variables. Here, you will find tables that list the different demographic values you will see in the application and a description for each.

Creating a custom variable

You can define custom variables to calculate demographic statistics relevant to your task. These custom variables let you make informed decisions when creating redistricting plans.

Steps:

1. On the Create ribbon, click Demographics.
2. On the Demographics dialog box, click Custom Variable.

   The Variable Calculator dialog box opens.

3. Click to select a value from Available Fields and the mathematical tools to generate a statement.

   The variables are categorized into folders whose names correspond with the Set column in the Demographics dialog box. You will see folders with the following names, for example, Universe, Standard VAP, Standard, and OMB.

4. Enter a variable name.

   The variable name is the name of the custom variable. Only letters, numbers, and underscores are allowed in the variable name. The first letter must be a letter, not a numeric value.

   Note:

   The variable name is automatically converted into all capital letters upon a save.

5. Enter a Long Name.

   The Long Name is displayed as a column header in any reports that you generate.

6. Select the display precision:
   • Use the up/down arrows to increase or decrease the precision.
   • Type a numeric value for the precision, and hit ENTER.

   The display precision allows you to determine the number of digits displayed after the decimal. The higher the display precision, the more accurate the variable calculation.

7. Check the cumulative value option to include cumulative values in the expression. When the Cumulative Value option is checked and you select an available field, the field will calculate that value in relation to the whole plan (Optional).

   Cumulative values include total calculations for the whole plan. When using the cumulative value, the expression is contained in dollar signs $. For example, $TOTAL$ is the expression for the total population in the plan.

   Noncumulative values focus on the geography level (for example, district, precinct, or territory). When using noncumulative values, the expression is contained in brackets [ ]. For example, [TOTAL] is the expression for the total district population.

   In the following sample noncumulative value expression, the result is a percent. In this case, the total number of White Non-hispanics in the district is divided by the total district population: [WHITENH]/[TOTAL].

   In the following sample cumulative value expression, the result is a percent. In this case, the total of White Non-hispanics in the district is divided by the total plan population: [WHITENH]/$TOTAL$.

   Note:

   Check Cumulative Value and select the field to include plan values in the expression. Uncheck Cumulative Value when you want to select fields at the geography level.

8. Click OK.

   The custom variable is added to the Demographics dialog box. The Field Name displays the variable name you defined above. The demographic set displays Custom to let you know this is a custom value. By default, only the Sum option is enabled for custom variables.

   Note:

   Once a custom variable is created, the variable is saved to your user account. Other Esri Redistricting Online users do not have access to view your custom variables. If you want to share a custom variable with other users, you can save the custom variable to file. Other users can then load the custom variable file to use in their Esri Redistricting Online sessions.

Saving a custom variable to file

While custom variables are automatically stored with your Esri Redistricting Online user account, you can save all custom variables to a file. You can share this file with group members, stakeholders, and other users for use in their own Esri Redistricting Online sessions.

Note:

The steps in this section assume that custom variables have been created. For detailed steps on how to create a custom variable, see Creating a custom variable.

Steps:

1. Create a custom variable. See Creating a custom variable.
2. Click Save.
3. Select a location to store the *.custom file and click Save.

   You can change the name of the custom file; however, ensure you keep the *.custom file type.

   The *.custom file is stored locally. The *.custom file contains all custom variables that are saved to your Esri Redistricting Online account. You can then share this *.custom file with other users, or for your records.

Editing a custom variable

Custom variables can be edited to fit with your changing business needs.

Steps:

1. On the Create ribbon, click Demographics.
2. On the Demographics dialog box, click Custom Variable.

   The Variable Calculator dialog box opens.

3. Click to select a variable from the drop-down menu.
4. Click Edit.

   The Edit Variable dialog box opens to confirm the variable you are about to edit.

5. Click OK.

   The custom variable is loaded in the Variable Calculator dialog box.

6. Modify the custom variable expression as needed.
   • Click to select a value from Available Fields and the mathematical tools to modify the custom variable expression.
   • You can also opt to manually edit the custom variable expression in the text box.
   • You can also modify the variable name, long name, variable description, and display precision.

   The variables are categorized into folders whose names correspond with the Set column in the Demographics dialog box. You will see folders with the following names, for example, Universe, Standard VAP, Standard, and OMB.

7. Click OK.

   The custom variable is updated.

Loading a custom variable file

Custom variables can be saved to a *.custom file for sharing and dissemmination between group members and users. You can load a custom variable file to add new custom variables to your Esri Redistricting Online account. The new variables in the *.custom file will be added to existing custom variables.

Note:

The steps in this section assume that custom variables have been created and a *.custom file has been saved locally. For detailed steps on how to create and save a custom variable, see Creating a custom variable or Saving a custom variable to file.

Caution:

If a custom variable exists in your session and you load a *.custom file that contains variables of the same name, the variables stored in the *.custom file will overwrite any custom variables upon loading.

Steps:

1. On the Create ribbon, click Demographics.
2. On the Demographics dialog box, click Custom Variable.

   The Variable Calculator dialog box opens.

3. Click Load.
4. Navigate to and select the *.custom file and click Open.

   The *.custom file is read by Esri Redistricting Online and all custom variables are loaded into the Variable Calculator dialog box and are displayed in the Demographics dialog box.

   Note:

   You will see no visible change if the *.custom file contains the same custom variables that already exist with your Esri Redistricting Online account.

   To use the newly loaded custom variables, you will need to turn on the variable in the Demographics dialog box.

Deleting a custom variable

Custom variables can be deleted if they are no longer relevant to your task.

Steps:

1. On the Create ribbon, click Demographics.
2. On the Demographics dialog box, click Custom Variable.

   The Variable Calculator dialog box opens.

3. Click to select a variable from the drop-down menu.
4. Click Delete.

   The Delete Variable dialog box opens to confirm the deletion.

5. Click OK.

   The custom variable is removed from the Demographics dialog box and the District Statistics dialog box, if the variable was visible at the time of deletion.

6. On the Variable Calculator dialog box, click OK to close.