How accurate are polls?

We can’t state anything with certainty, because anything can happen. What we can do is measure a moment in time and then keep measuring moments and project what may happen.

Do you think the media misuses polls or takes them out of context?

Sometimes they do, or they make the same mistakes that consumers do. Like, you can’t mix and match different pollsters. So if Company A has McCain up by seven points and Company B has him down by three, you can’t say that he’s up by four. Another mistake is not accounting for a margin of error. If Company A has Obama up by two and Company B has McCain up by one, they’re actually saying the same thing, because a margin of error exists. In general, consumers should look at many different polls and observe the overall trends.

On Election Day 2004, you said that John Kerry would win. Can we trust you?

That was a bit of hubris on my part. A couple of states such as Ohio were too close to call, so I made an assessment based on pre-election polls and exit polls. But that experience led me to drop the prediction part of the business and stick to polling.

http://www.parade.com/hot-topics/0808/how-to-look-at-a-poll