Spatial Weighted Average

[ghuttofriman]

Hi all! I have a poverty rate by zip code field and a polygon field. Any ideas on how to calculate the weighted average of the poverty rate based on the amount of the polygon that touches each zip code (poverty rate)? TIA!

[FinnCharlton · Accepted solution]

Hi @ghuttofriman ,

1. You'll need to find a shape file for each zip code, this thread might help https://gis.stackexchange.com/questions/2682/seeking-sources-for-us-zip-code-boundaries 
2. Import all shape files.
3. Append the polygon onto each row with a zip code shape.
4. Use the spatial process tool to create a new shape file on each row - just the intersection of the two.
5. Calculate the area of each intersection.
6. Then calculate the weighted average. Multiply each poverty rate by its intersection area. Add the values from all rows together. Divide by the sum of all intersection areas.

Hope this helps!

[ghuttofriman]

Thank you so much! Followed this solution except I used zip codes from the allocate input tool and then used a spatial match instead of the append to match my polygons with the zip code polygons and used the weighted average tool at the end. Appreciate it.