On Sat, 31 Jul 2004, Doug Henwood wrote:
> Zogby also adjusts his sample based on historic trends and his
> judgment of "what is happening on the ground" in a particular race,
> and it is this imposition of his own judgment that disturbs many
> pollsters.
>
> He will, for example, reduce the proportion of 18- to 24-year-olds in
> his sample of self-described likely voters if he suspects on the
> basis of past voting history and the "lay of the land" that a sample
> contains too many younger people. He also, on occasion, adjusts the
> religious composition of his sample if he suspects he has over or
> under-represented one faith.
--The estimation of sampling error (margin of error) in this kind of sampling procedure assumes independent elements drawn randomly from a large population. The procedure described above clearly violates this assumption; thus the sampling error reported on the Zogby polls is a meaningless number with no basis in reality.
He really gets away with this?
Miles