Public opinion polls in the Nashville mayoral contest (and other multi-candidate races) should be analyzed with care because of the high potential for error, according to Vanderbilt Distinguished Professor of Political Science John Geer.
“The chance that any single poll in the Nashville mayor’s race could be misinterpreted is dramatic, and the possibility that an erroneous poll could sway the outcome is something that we all want to avoid,” Geer said.
He said that the reasons to be cautious are numerous:
- Polls are becoming less reliable due to the use of cell phones and unwillingness of many people to be surveyed. Hence, any one poll must be treated with caution.
- Polls about local elections are even more problematic because the researcher needs to identify the likely voters in a low turnout election.
- Local elections tend to have voters with not strongly formed views, introducing more potential for error in polling.
In the Nashville mayor’s race, the top two candidates move on to a run off if no one receives 50 percent of the vote. Some polls have shown Bob Clement to be the frontrunner by a wide margin, but there is a closer spread among the other candidates in these polls. Geer said that it is very likely that these candidates will be closely bunched, making the margins reported in the polls very unreliable.
Geer, therefore, is concerned that whoever comes in second in a poll for the Nashville mayor’s race could receive an unfair bump if undecided voters perceive that candidate most likely to be in the runoff.
“Unless there is at least 6 to 7 percent margin of difference between second and third place in the race, I would not put a tremendous amount of faith in a single poll,” Geer said.
Geer teaches and writes about campaigns, elections, presidential transitions and public opinion. His books include From Tea Leaves to Opinion Polls: Politicians, Information and Leadership (Columbia University Press).
Editor’s note: Geer can be reached at 802-563-2326 or by email: john.g.geer@vanderbilt.edu.
Media Contact: Ann Marie Deer Owens, 615-322-NEWS
annmarie.owens@vanderbilt.edu