Reply #15: actually the national is built on 4 regional polls [View All]

[chorti]

The national poll is simply built on the four regional polls. They are simply added together (weighted by region) to form the national poll. The regional polls use some of the same precincts as the state polls, but not all precincts used in the state polls are used in the regional poll. The regional polls are built to get an accurate regional (and, therefore, national) demographic. The national poll had about 13,000 respondents, which is just the sum of the four regional samples.

All told, in the 51 state/district exit polls, about 100,000 were polled. Because we have an electoral college system, the exit poll is meant to get a very representative sample from each state. But the aggregate of the state polls may give a rather different result than the national poll because they are drawn from two different samples. You can contrust an alternate national voting demographic by creating a national weighted average from the 51 state exit polls. Anyone want to take that on?