Many times, the best way to find out something about a group of people is to simply ask them. However, that isn’t always a surefire source for truth. The gap between what we do and what we say we do is wide enough to support entire industries.
For instance, the people who publicly tell you they back a particular candidate might vote for someone else behind the privacy curtain. We all like to be thought of as smart, progressive, dependable, creative, sexy, good listeners and caring. The temptation to bend the truth on a question is strong, even when we don’t know the questioner. We are just as prone to lie to the Gallup or Nielsen caller as we are to the woman across the street who can’t keep a secret.