Why Do Election Polls Vary So Much?

October 30, 2012 - 7:00am

Election Day is a week away and it seems everywhere you look, there's a new poll on TV, online, or the radio. But they don't all say the same thing. Host Michel Martin takes a look at why the polls vary, and what they tell us. She talks with Stanford University professor Simon Jackman. He teaches political science and statistics.