Social Desirability Bias: How Psych Can Salvage Econo-Cynicism
By Bryan Caplan
The strongest evidence against the economic way of thinking is the way that people describe their own behavior. People rarely announce, “I’m looking out for number one.” Businesses rarely advertise, “Our own profit is our top priority.” Students rarely declare, “I just look for easy A’s.” Workers’ resumes rarely identify their career goal as, “Money!” To hear a CEO trumpet, “I’m retiring to have more time with my material possessions,” you must turn to The Onion.
Economists have a long-standing defense mechanism against this mountain of evidence: Behaviorism. Milton Friedman told us you can’t believe what people say. Many of us still believe him. But this position isn’t just self-refuting; it’s absurdly dogmatic. Virtually every person alive professes noble aims, so economists invoke the methodological principle that “Words count for nothing”? If that’s our best response to ubiquitous empirical evidence, the world is right to dismiss us as a cult.
Fortunately, there is a far more compelling response… with one big catch: Economists have to outsource their intellectual defense to psychologists. Like economists, psychologists are deeply skeptical about mere words. They too hold a cynical view of human nature. To defend it, though, they don’t rely on half-baked philosophy of science. Instead, they carefully measure and compare the divergence between what people say and what they do.
Social desirability bias is the tendency of respondents to
answer questions in a manner that will be viewed favorably by others. It
can take the form of over-reporting “good behavior” or under-reporting
“bad,” or undesirable behavior. The tendency poses a serious problem
with conducting research with self-reports, especially questionnaires.
This bias interferes with the interpretation of average tendencies as
well as individual differences.
Topics where socially desirable responding (SDR) is of special
concern are self-reports of abilities, personality, sexual behavior, and
Other topics that are sensitive to social desirability bias:
- Personal income and earnings, often inflated when low and deflated when high.
- Feelings of low self-worth and/or powerlessness, often denied.
- Excretory functions, often approached uncomfortably, if discussed at all.
- Compliance with medicinal dosing schedules, often inflated.
- Religion, often either avoided or uncomfortably approached.
- Patriotism, either inflated or, if denied, done so with a fear of other party’s judgement.
- Bigotry and intolerance, often denied, even if it exists within the responder.
- Intellectual achievements, often inflated.
- Physical appearance, either inflated or deflated
- Acts of real or imagined physical violence, often denied.
- Indicators of charity or “benevolence,” often inflated.
- Illegal acts, often denied.
Why is the psychologists’ approach so superior to the economists’? Simple. Economists reject all-pervasive testimony on lame methodological grounds. Psychologists, in contrast, aggressively cross-examine this all-pervasive testimony, and empirically expose its all-pervasive perjury. Despite what they say, people really are selfish, businesses really are greedy, students really are lazy, and workers really are materialistic. Econo-cynicism has a firm basis in psychological fact.
Of course, a “firm basis in fact” is hardly the same as “unvarnished truth.” Some deviations from narrow self-interest handily survive cross-examination. Voting really is largely unselfish, workers really do obsess about nominal pay, and managers sincerely hate firing anyone. The point, though, is that the economic way of thinking is on much stronger empirical ground than economists themselves have managed to demonstrate. Though we’ve often belittled psychology, it’s ably served us for decades. Perhaps if economists give psychologists some much-deserved credit for Social Desirability Bias, they’ll be more eager to vouch for the value of what we do.