MapInfo Redistricting Window Rob Tozier 14 th Annual GeoElections User Conference

MapInfo Redistricting Window 14 th Annual GeoElections User Conference As you can see our block table needs to be updated with the new Congressional district numbers.

MapInfo Redistricting Window 14 th Annual GeoElections User Conference First edit the parameters of our VTDBLK1. GeoElections > Parameters > Select Districts and then Select Edit

MapInfo Redistricting Window 14 th Annual GeoElections User Conference Edit/Rename the existing column for Congress to Congressional_2012. Add a new district called Congress CNG Width 4. This will contain our new data from the equivalency file.

MapInfo Redistricting Window 14 th Annual GeoElections User Conference Step 2: Table Maintenance > Table Structure and select our the current VTDBLK1. Rename the CNG column to CNG_2012. Add a column to the block table called CNG, this is the column that will be updated with the data from our equivalency file.

MapInfo Redistricting Window 14 th Annual GeoElections User Conference Step 3: In order to update our CNG column we need to match a field in both our VTDBLK1 and our DOJ Equivalency File. We can match on the first 15 characters in the code, but have to remove the split suffix. We can update the Code field with the first 15 characters of this field. Left$(Code,15)

MapInfo Redistricting Window 14 th Annual GeoElections User Conference Step 4: Open the equivalency file and run Table > Update Column. Update the VTDBLK1 CNG column getting the values from the equivalency file joining where Code matches Code, obtaining the value of the Congressional District. You can see the CNG field is now populated. Results

MapInfo Redistricting Window 14 th Annual GeoElections User Conference Step 5: With the CNG field updated, we need to restore the Code field to document the splits that were temporarily removed. Table > Update Column Table to update VTDBLK1 column to update Code. Getting the values from Name. Results

MapInfo Redistricting Window 14 th Annual GeoElections User Conference Step 6: Run MapMaker to create a 2015 Congressional District Map to use as a layer for reprecincting your county. Results

MapInfo Redistricting Window 14 th Annual GeoElections User Conference Step 7: Open your VTDBLK1 and your newly created Congressional_Distri cts_2015 in a new mapper window. Select Window > New Redistricting Window.

MapInfo Redistricting Window 14 th Annual GeoElections User Conference The source table will be VTDBLK1 using the district field Precinct. Add the Sum(VOTER_POP) to the list of fields to browse and click ok.

MapInfo Redistricting Window 14 th Annual GeoElections User Conference Now that the redistricting window is open organize your workspace accordingly. Place the District browser to the right, size the view just for what you need to see. Do a style override on your Congressional_Districts_20 15 so it is visible and place it as the top layer.

MapInfo Redistricting Window 14 th Annual GeoElections User Conference In order to assign a block to a precinct there are 4 steps. Step 1. Select a block in the precinct you want to assign new blocks to. Step 2. Select Set Target District Step 3. Select new block(s) to add to existing precinct. Step4. Click Assign Selected Blocks

MapInfo Redistricting Window 14 th Annual GeoElections User Conference The District browser keeps track of the count of blocks in each district/precinct and the sum of the voter pop when you add and remove blocks from each district/precinct. Results Precinct M013 Count 12 Sum(VOTER_PC 1028 Precinct M013 Count 13 Sum(VOTER_PC 1192