Dueling Polls

With only 13 days until the general recall election, the only thing competing for voters’ attention as much as TV ads are polls. Who’s up, who’s down. There’s another “who” involved. Namely, who did the poll? In the last week we’ve seen two polls done by two different polling operations produce two very different results.

The first poll was done by respected Professor Charles Franklin, the pollster and Political Scientist on loan from the UW-Madison to the Marquette University Law School. His survey gave Governor Walker a six-point lead over Milwaukee Mayor Tom Barrett: 50-44 among likely voters with just 3% saying they’re undecided.

The second poll, released by the Barrett campaign yesterday, shows Walker up by only 3%, not 6%. That poll was gathered by Washington-based Greenberg Quinlan Rosner between May 19-May 21, more recently than the Marquette Survey. Since that poll was commissioned by the Barrett campaign itself, its findings are questionable by definition, right? We asked Professor Franklin.

“Greenberg Quinlan Rosner (GQR) is a well respected Democratic firm with a reputation for credible polling,” Franklin said. ”I take their work very seriously and respect their pollsters”

Franklin went on to say that while all polls are showing Walker ahead at this time, the thing to consider is how those leads are impacted by the surveys’ plus-or-minus value.

“Since April 15, polls from five different pollsters have Walker leads of 5,1,5,6,9, 5 and now 3 in the GQR. So GQR is within that range, if a little more favorable to Barrett, said Franklin. “Certainly a lead of 3 is within the margin of error of the three 5s and one 6 point lead. And it is certainly possible that the margin has tightened over the week since PPP and MULaw put it at 5 or 6 points.”

It seems that Professor Franklin’s biggest lesson is to avoid looking at polls independent of one another. Looking at them in sum reveals deeper meaning.

“Of recent polls, MU Law has had the smallest Walker lead among likely voters, 1 point, and a 6 point lead. Average those and you get 3.5 points. PPP has two polls, both a 5 point Walker advantage. In that light, GQR is not out of line with those average results.”

“Ultimately a difference of 2 or 3 points in the polls means little, given margins of error of 4-5 points in each of these polls. And in the end it is the voters on June 5 who will settle the matter.”