Nate Silver's analysis is fatally flawed ?

[kentuck]

http://www.huffingtonpost.com/michael-p-mcdonald/does-early-voting-show-re_b_773236.html

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Nate Silver, political statistician extraordinaire, has posted an analysis of early voting partisan registration statistics, in states that report them, drawing upon a story by Molly Ball in Politco. I'll cut to the chase. Here is what Nate concludes in his analysis, which is largely consistent with Molly's headline that early voting shows "Signs of GOP Passion":

So, the various estimates of early voting data each show an edge for Republicans: their voters have been slightly more inclined that Democrats in most states thus far. Under the most favorable set of assumptions for them, their advantage is around 9 points; by the least favorable set of assumptions, it is more like a 4-point edge.

Unfortunately, Nate's analysis is fatally flawed. Molly provides the key damning evidence against Nate -- and against her own headline.

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In other words, in 2006 Democrats and Republicans were even in party registration among California's early voters. In 2010, so far registered Democrats have a plus 4 advantage over Republicans. Democrats are doing better among California early voters than in 2006 -- the year that Democrats took control of both chambers of Congress -- and this is evidence for GOP passion? For Nate, the answer is, "Yes." He reaches the conclusion that because there are far more registered Democrats in the state than Republicans, the 2010 early voting percentages will translate into a plus 9 advantage for Republicans over their baseline support in the state when the vote is tallied.

.........more

[Dawson Leery]

1. Nate must be using tea party "logic" shall we say, on this matter:

In other words, in 2006 Democrats and Republicans were even in party registration among California's early voters. In 2010, so far registered Democrats have a plus 4 advantage over Republicans. Democrats are doing better among California early voters than in 2006 -- the year that Democrats took control of both chambers of Congress -- and this is evidence for GOP passion? For Nate, the answer is, "Yes." He reaches the conclusion that because there are far more registered Democrats in the state than Republicans, the 2010 early voting percentages will translate into a plus 9 advantage for Republicans over their baseline support in the state when the vote is tallied.
:crazy:

[KansasVoter]

2. Until Nate is proven wrong Election day I trust him!

[TheWraith]

3. Silver's estimates trend conservative.

He predicted Obama to get 349 electoral votes, and Obama actually got 365. He's also underrated Dem chances in most of the special elections.

[tritsofme]

4. Nate Silver's response here:

http://fivethirtyeight.blogs.nytimes.com/2010/10/25/a-second-pass-at-early-voting-totals-now-with-extra-skepticism">A Second Pass at Early Voting Totals: Now With Extra Skepticism
By NATE SILVER

I’ve gotten a lot of pushback on my post from Sunday night about early voting figures. Michael P. McDonald of The Huffington Post, for instance — whose work I referred to in my article – calls it “fatally flawed” and suggests I have erred by comparing early voting totals in each state to party registration figures. Instead, he thinks, the proper comparison is to early voting figures from past years.

My article consisted of essentially two different parts. About 600 words were devoted to critiquing the notion that the early voting data – particularly in the way that some other analysts are using it — tells us much of anything at all. The other 600 words (the part that Mr. McDonald criticizes) were devoted to a comparison of the early voting figures against voter registration data in each state, which I suggested revealed a small “enthusiasm gap” in favor of Republicans.

If you take just one point from yesterday’s article, I’d really prefer it be the former, more skeptical one. A lot of the analyses of early voting figures are quite flawed. I’ll take some blame here for having selected a poor headline, which did not emphasize this point enough.
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