Sunday, July 13, 2008

Why Do You Lie? The Perils of Self-Reporting

I read with interest this informative article by Stephen J. Dubner in Freakonomics / NY Times Blog about how he is always surprised at how easily, and cheaply, we humans lie.

I guess, may be if there is a penalty for telling lies, we would behave properly. While we teach children "Telling lies no papa", we ourselves are quite capable of telling lies and do tell lies, if it suits us. May be that's what this research indicates wherein people say they possess certain things, when they actually don't possess them and similarly deny possessing certain things, when they actually do possess them. Probably, the benefit of telling lies, either material or otherwise, outwieghs the costs involved, enticing people to tell lies, even as they teach their children "Telling lies no papa".

Some highlights from the Freakonomics / NY Times blogpost -

  • Have you ever been in a conversation about, say, a particular book and been tempted to say you’ve read it even though you haven’t? I am guessing the answer is yes. But why would anyone bother to lie in such a low-stakes situation? The book lie is what you might call a lie of reputation: you are concerned with what other people think of you. Of the many reasons that people lie, I have always thought that the lie of reputation is the most interesting — as opposed to a lie to gain advantage, to avoid trouble, to get out of an obligation, etc.
  • A new paper by the economists Cesar Martinelli and Susan W. Parker offers some fascinating insights into lies of reputation. It is called “Deception and Misreporting in a Social Program,” and will be published soon in the Journal of the European Economics Association.
  • It turned out that a lot of people underreported certain items that they thought might exclude them from getting benefits. These include cars, trucks, video recorders, satellite TV, phone, washing machine etc. That’s not very surprising: you might expect people to lie to gain the advantage of a welfare benefit. But here’s the surprise - some items which applicants said they had but in fact did not and these include toilet, tap water, gas stove, concrete floor, refrigerator etc. So 4 out of 10 applicants without a toilet said they had one. Why?
  • Martinelli and Parker chalk it up to embarrassment, plain and simple. People who were desperately poor were also apparently desperate to not admit to a welfare clerk that they lived without a toilet or running water or even a concrete floor. This is one of the most amazing lies of reputation I can imagine.
  • The Martinelli-Parker paper may have broad implications for not only poverty programs but any kind of project where the data are self-reported. Think about the typical survey on drug use, sexual behavior, personal hygiene, voting preference, environmental behavior, etc.
  • Here’s what we once wrote, for instance, in an article about the lack of hand hygiene in hospitals - In one Australian medical study, doctors self-reported their hand-washing rate at 73 percent, whereas when these same doctors were observed, their actual rate was a paltry 9 percent.
  • But as often as we or anyone else writes about the perils of self-reporting, the Martinelli-Parker paper really gives the whole topic a foundation to stand on. Not only does it deliver a surprising insight into why we lie, but it is also a sobering reminder to naturally distrust self-reported data — at least until some scientists enable us to peer into one another’s minds and see what’s really going on there.