Must Read WSJ Article

Legacy blog posts Weighting by Party

In a crush of work yesterday, I somehow missed a terrific article by Sharon Begley in the morning’s Wall Street Journal, “Public-Opinion Polls Diverge Because They Are Still Partly an Art.” Sound familiar? Attention reporters: Begley’s piece is absolutely, positively a must read. If you have time for only one polling methodology article, this is the one.

It’s tempting to quote it all – and I’ll certainly quote more in the coming weeks – but for now, here’s how Begley disposes of the party ID weighting debate:

Gallup does not adjust for party self-identification, and neither do many other major polls. Zogby International, however, treats party affiliation, as given by voters in exit polls in 2000 and other recent elections, much like age or sex, increasing the weight of whichever party is undersampled.

But every scientist I asked has grave qualms about that. Party affiliation can change in four years, or even overnight, as Prof. [Cliff] Zukin [professor of public policy at Rutgers University] found in a 2003 study: When people lean toward, say, a Republican, they then tell poll takers they are Republican. If more self-identified Republicans make the cut of “likely voters,” then that reflects that more of the former are likely to vote. [emphasis added]

The Journal has kindly made this article available free of charge. As they say, read it all.

Mark Blumenthal

Mark Blumenthal is political pollster with deep and varied experience across survey research, campaigns, and media. The original "Mystery Pollster" and co-creator of Pollster.com, he explains complex concepts to a multitude of audiences and how data informs politics and decision-making. A researcher and consultant who crafts effective questions and identifies innovative solutions to deliver results. An award winning political journalist who brings insights and crafts compelling narratives from chaotic data.