With the proliferation of public and private polling this election season, one needs a scorecard to keep them all straight — both in terms of predictions and accountability. Last night’s big winner in terms of accuracy — at least in North Carolina — was Zogby. He predicted a 14% Obama win in the Tar Heel state, which turned out to be right on target. His polls also nailed the Pennsylvania race. Zogby was a little off in Indiana. He was one of only a few pollsters to predict a narrow Obama win. And while Clinton did end up winning in the Hoosier state, the margin was much narrower (and closer to the Zogby numbers) than many pre-election polls predicted. American University political scientist Brian Schaffner posts this interesting chart that evaluates the accuracy of many public polls in yesterday’s two primaries. Turns out Survey USA was the big loser, according to Schaffner. They predicted a Clinton blow out in Indiana and only a 5% Obama win in North Carolina. Schaffner’s chart shows how final predictions from pollsters ARG, PPP, and Insider Advantage worked out in both states. And as he reminds us, all of the pollsters need a dose of humility and perspective. “Of course, lest any pollster get a big head, these pollsters have been in the opposite positions (Zogby as the big loser and Survey USA as the big winner) in earlier primaries this year.”
