Blame a pair of SMU profs for those squiggly lines on your TV during the Presidential debates

CNN has used this graph during the Presidential debates and the vice-presidential encounter to show the world how a group of 30 "undecided" voters are reacting in real time to what the candidates are saying. Now I've learned that CNN's focus group was managed by two professors of communications at SMU, Rita Kirk and Dan Schill. Here's an excerpt from a story in American Prospect that tries to explain the whole process:

Kirk instructs participants to adjust their dials based on whether they have "a favorable or unfavorable response" at any given moment, but leaves determining what that means to the individual.

Some response are fairly consistent. "Audiences don't like it when candidates fight with each other," Kirk says. And, in a bit of news surely heartening to Jim Lehrer, "audiences want people to follow the rules, so any time you see rule-breaking they dial it down." Facts are preferred to rhetoric, and while audiences don't typically like personal anecdotes, says Kirk, if "they believe it's a natural expression, they react very favorably." Joe Biden's misty-eyed moment at the end of the vice-presidential debate was a big hit.

These are heartening findings, but there's no way to know if they represent participants' true reactions or what they think they should feel -- as Kirk acknowledges, a significant body of research shows negative ads work even though voters, independents especially, claim to hate them.

What's more, the process of dialing itself changes how the participants experience the debate. "[Participants] say they pay more attention, because they are focusing on the words," says Kirk.

Later in the story, it quotes one Cliff Zukin, director of the public-policy program at Rutgers University and former head of the American Association for Public Opinion Research, as saying the methodology of the SMU profs is all a bunch of hooey: "It has no scientific validity -- it's not a sample of anything that has generalized validity."

But then these are professors of communications, not of research or statistics. Whaddya expect?