You wrote:
Party affiliation is not a static, unchanging demographic attribute like sex, race, or even religion (which can change, but not readily).
jvwjr addressed that here:
One of my assumptions that some might disagree with is that I feel that the political party affiliation sample composition should remain fairly consistent. Some believe that from month-to-month people re-identify with another party depending on how a particular candidate is faring in the polls. If that were so, then there would not have been any "Reagan Democrats" in the 1980s, they would have converted and become "Reagan Republicans". They may have voted for Ronald Reagan, but they still voted for Democrat congressional candidates, so to me they remain Democrats. I believe that party affiliation changes are slow, not detected nor truly documented by monthly fluctuations by polling organizations.
So his treatment of party affiliation is the result of a deliberate assumption rather than an oversight. In fact, if I've understood correctly, he considers this assumption to be a correction to Newsweek's results.
Dear Yardstick,
I agree that long-term party affiliation changes slowly over time.
But I think that a small but significant percentage of respondents will temporarily change their party self-identification in the wake of a party's convention.
By election time, it will have likely shifted back, but for a few days, some number of folks who normally self-identify as Democrat or Independent may identify as Republican.
I know that the ultra liberal fellow who works for me came in after the Republican Convention just about ready to vote for W. At that moment, I think he'd have been a little ashamed to self-identify as a Democrat.
But in a week, I'm sure he'll be back to being a yellow dog Democrat ready to drink Kerry Kool-Aid.
I think this is why pollsters' random samples see increases in the affiliation of the party that just held its convention. It isn't a long-term change, but it does affect the sample in the short term.
sitetest