Until now the Meta-Analysis has used all polls in the Pollster.com database. However, a source of many outliers is Zogby Interactive, which uses Internet-based polling. Recently we dropped them. The EV estimator will be calculated without their data.

The Zogby Interactive approach potentially gets around biases that may occur in landline-based surveys, the polling industry standard. For example, millions now have cell phones but no landlines. On the down side, Zogby Interactive is still working out the kinks in this method. For example, they reported some distinctly odd results during primary season. For now I’m dropping them.

At some point in the near future we will probably recalculate the history without their data. For now, I’ll leave it alone.