According to a new poll, Anthony Weiner is trailing City Council Speaker Christine Quinn by nine points in the New York Democratic mayoral primary. But on Monday, he was up three. What gives?
We spoke by phone with Andrew Gelman to find out. Gelman is a professor of statistics and political science at Columbia University who has contributed to The Times' FiveThirtyEight blog in the past.
First, the details on the polls.
|Monday's poll||Today's poll|
|Results||Weiner, up by three (25 to 22%)||Quinn, up by nine (27 to 18%)|
|Margin of error||3.6 percent||4 percent|
|Polling firm||Quinnipiac University||Siena Research Institute|
|Sample size||738 registered Democrats||1,010 registered Democrats|
|Polling dates||Monday, July 8 — Sunday, July 14||Tuesday, July 9 — Monday, July 15|
While he wasn't familiar with these particular polls, Gelman explained a few possibilities. The first: "Public opinions can change." Even if the poll was conducted over largely the same time period, "a primary election campaign for mayor can be very volatile," he explained. "You have many candidates and don't want to waste your vote," meaning that people may be more likely to be willing to change their minds, especially since New York City Democratic primaries don't exactly include a broad range of political philosophies.