An Obama Effect?
With an African-American candidate on the presidential ticket for the first time in history, there has been a lot of talk about “the Bradley effect” (or the Dinkins effect, or the Wilder effect). Obama’s numbers are inflated, the thinking goes, because a large number of white respondents will tell pollsters they are going to vote for a black candidate, then turn around and vote for his or her opponent on Election Day. In light of these dynamics, should we take the current polling numbers at face value?
A few weeks ago John described recent work by Dan Hopkins on this topic (a paper that I’ll return to later this week). But the accuracy of the polls is something I’ve thought about for a while. Ten years ago, I wrote a paper entitled “The Two Faces of Public Opinion” which advanced an argument consistent with the Bradley effect. I argued that public opinion polls may overstate support for racially liberal policies (in this case, government efforts to integrate schools). My analysis revealed that those individuals who harbor anti-integrationist sentiments, but worried about social concerns, were likely to hide their socially unacceptable opinions behind a “don’t know” response. In a similar vein, pre-election polls in electoral contests which involve candidates of different races offer a situation where individuals might be loath to express their true candidate preferences for fear of appearing racist. Some individuals who are apprehensive about voting for black candidates may declare themselves undecided rather than come out and say that they oppose a black candidate.
I examined data from a 1989 New York City Mayoral election. There, the black candidate David Dinkins held a fourteen- to eighteen-point advantage over his white opponent Rudolph Giuliani in polls taken only days before the election, but ended up winning the race by less than two percentage points. Correcting the polls using statistical techniques that accounted for the “don’t know” improved the predictive power of those polls. Clearly, some people who said they didn’t know how they were going to vote in fact did know – they just didn’t want to tell us.
Given these results, should we discount Obama’s polling performance accordingly? I think not, for reasons I will elaborate over the next couple days. Put simply, the popular interpretation of the Bradley effect is overly simplistic. Only in those circumstances where voters face significant cross pressures will they have incentive to dissemble to pollsters. In the New York City election, for example, Dinkins ran as a Democrat in an overwhelmingly Democratic city. In the current contest I do not think that voters will be subject to pressures great enough to fundamentally distort the polls.
Tomorrow, I’ll talk more about the history of polling in bi-racial elections.
Comments
When Reagan campaigned in 1980, he was not perceived as too old, primarily because of his appearance and his speaking abilities (including acting skills). McCain is different: he looks old, does not speak well and lacks charm and wit (his zingers to the contrary). I picture Tim Conway’s old man routine on TV when I see McCain on TV, especially with his stilted hand and arm movements. He is repetitive, even with mistakes. So maybe there is a counter to the Bradley effect: The Tim Conway effect.
Posted by: Shag from Brookline | August 20, 2008 02:54 PM
Clearly, some people who said they didn’t know how they were going to vote in fact did know – they just didn’t want to tell us.
and how is that different than any other poll ever?
Posted by: BillCinSD | August 20, 2008 06:35 PM
This speaks directly to a thesis posited by James H. Kuklinski, Michael Cobb and Martin Gilens in their 1997 paper “Racial Attitudes and the ‘New South’.”
Kusklinski et. al. argued that a concept they called social desirability was at work when racial prejudice was prevelant in attidudes expressed by white, Southern males, in particular. Ultimately, there has been little progress in racial attitudes in the South, insofar as these attidudes are no longer expressed in social situations due to fear of a backlash from their peers. Rather, white, southern males simply don’t express their attitudes outloud or lie about their attitudes to others.
While Kuklinski et. al. found that these attitudes were concentrated primarly in the South, they found that these social desirability effects did exist in the non-South, as well, though it was to a lesser degree.
This thesis has been running around in my head for days when I read about the Obama polling numbers. It concerns me.
Posted by: Kati | August 20, 2008 07:14 PM
Think of it - political science was conceived as the effort to predict political outcomes. Polling was an important tool for the “scientist.” However, it turns out that people are not as predictable as the motions of planets. So, the science of politics now must expend enormous energy trying to correct for the unpredictability of polling. In the end, it’s really only a big guess with virtually no predictive ability. And yet, no one will acknowledge the nakedness of the emperor, much less laugh at his ridiculous pretensions….
Posted by: Anti-Climacus | August 23, 2008 01:11 AM