The psychologist who conducted the survey is now at Ohio State University.
The table was set up at a shopping mall well in advance of the November election. Potential voters were asked to listen to recorded statements about the Republican and the Democrat in the race and then press one of five buttons, which represented a range of opinions from "strongly agree" to "strongly disagree."
What the volunteers did not know was that psychologists were measuring something besides their opinions: After each statement about the candidates, a microprocessor started a clock that silently counted off the seconds until the volunteers hit one of the buttons.
Every answer from every volunteer, in other words, measured the time delay in coming up with that opinion.
Beginning the day after the election, psychologists telephoned the volunteers to ask how they had voted. People who had answered quickly were nearly twice as likely to have actually voted for the candidate they said they were going to support, compared with those who were slow in coming up with their answers.
The experiment, conducted ahead of the 1984 presidential election by Russ Fazio, a psychologist now at Ohio State University, was a sober reminder that people's statements about their political choices do not always predict how they end up voting.
What was found
A wide variety of subsequent experiments show that measuring time delays when people respond to opinion surveys can tell a political campaign something far more important than what people think at that moment -- it can tell them what a voter is likely to do Election Day.
"For every second longer they take to respond about who they are going to vote for, the probability they are going to turn out and cast a vote for that party drops by 8 percent," said John Bassili, a psychologist who has studied how response time predicts voting behavior.
"If they pause for five seconds, the chance they will vote for whom they say they are going to vote for is reduced by 40 percent," said Bassili, who works at the University of Toronto at Scarborough.
Pollsters, of course, regularly ask people nowadays not only what they believe but how strongly they believe it. But experiments show that time delays are a better predictor of the strength of people's opinions than the explicit statements people make about themselves.
Fazio and Bassili, who are interested in what such results say about human decision-making, do not know how widely such techniques are being used ahead of the midterm elections. Both telephone surveys and computer polls make it relatively simple to measure time delays.
Here is why your speed in answering is tied to the certainty of your views: Voters with strong political views readily identify themselves as liberals or conservatives. When asked their views on a subject -- say, gun control or abortion, or which candidate they support in an election -- they view the question through their political self-image and produce a ready answer.
Though the idea of being a knee-jerk liberal or conservative may be unfashionable, such group affiliations serve as an efficient shortcut for the brain to manage complex information.
People without strong political affiliations have to think more when asked their views. They may reach the same conclusion as the group that was quick, but the fact that they had to weigh multiple issues means that as new information comes along, they are more likely to change their minds, explained Robert Huckfeldt, a political scientist at the University of California at Davis.