Blocks with zero population in California about census-2020

[rootsmusic]

I don't know if you've already checked VEST's data, which RDH is beginning to validate. You can run RDH's Jupyter notebook for VEST's Hawaii data. By the way, you can volunteer, apply for a job or a paid fellowship with RDH.

[christopherkenny]

Yeah, zero population blocks are blocks that have no people living in them by the 2020 Census count +- noise. I don't think there's actually any hidden meaning there.

As for blocks that have election data but zero population, that's introduced by the estimation across geographies. Some blocks crosswalk into new blocks that now we measures as having zero population. This is a simple estimation strategy without constraints on that. Perhaps there's an additional step to be taken to zero out zero population blocks and make sure that those votes are otherwise allocated. Thoughts @CoryMcCartan?

I think we intended the blocks to be a stepping stone for 2020 geographies, but CA, OR, and HI do not appear to have Census Bureau VTDs, so we just report the estimated data at the block level with no aggregation.

[CoryMcCartan]

I think this is mostly population changes + DAS noise

[kuriwaki]

I see. I didn't realize there were so many blocks with 0 population (USCB said 2 million blocks with 0 pop in 2010!). It would be great to somehow aggregate those three states to precincts but that's for another issue.