I am new to using QGIS. I have two polygon layers:
- Voronoi of Access Points
- Census block maps with population
I want to get number of people covered by each Access Point (Assuming uniform distribution of people within the blocks). I have tried two different approaches, both failing to get me the correct answer.
- Use join by location...sum of people covered by APs is 3x of people in the area.
Multiple step approach
- Calculate area of each block
- Intersect block layer with voronoi, to clip blocks on AP boundary
- Recalculate the area of clipped block layer
- Calculated proportional population based on new clipped area and original area
- Use join by location....sum of people covered by APs is 2x of people in the area.
In Join by location, I am using summary option for sum of all intersecting features.
In Mapinfo I am able to use proportional sum to get the number of people under each AP's coverage. I'll really appreciate if someone can point me in the right direction.
Thanks, Manish