Wednesday, September 19, 2012

Cognitive Bias: the Barnum Effect

Ever run into an ad that reads something like this (real current website of a real company, name blurred)

Generic statements that promise things like "people from all walks of life... enjoy the benefits of the ... opportunity", and "you don't need any special skills or experience" reads just like any ad, right?

"It's a natural process to become a successful [redacted] distributor. Anyone can succeed in this business." Wow, guess that means you!

You've been subject to the "Barnum effect", in that you attribute a bit more "oomph" to the generic statement (you can do it!) than you should. People trying to persuade you to do something knows this intimately.

Barnum effect is a variant of "subjective validation". Basically, you took the generic advice (like those found in fortune cookies, or astrology forecasts) and found some deeper personal meaning. It's called "Barnum Effect" because P.T. Barnum, of the circus fame, has a special line: "we have something for everybody!"  Barnum is well known for his psychological manipulative skills (i.e. showmanship) and psychologist Paul Meehl seem to have named the effect after P.T. Barnum.  Though another psychologist, Robert Fourer, made the same observation in 1948, so it's also known as the Fourer Effect.

How do you spot Barnum effect being used on you or anybody else?

First, consider the alternative: is the advice / observation generic enough so it would apply to just about ANYBODY, not just the reader?

Second, is the advice more of a compliment, that it makes you feel better about yourself or your chances? That you're being "buttered up" for something?

Third, what do they really want? In this case, it's to sign up as a distributor (i.e. pay them for some of their products, and promise to sell more).

In other words, basic skepticism is all you need.

Once you account for its effects, you can then make adjustments to your expectations.
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  1. how do we know when its a problem or not?

    1. You just have to be skeptical about all claims, even when people are praising you. We tend to overestimate ourselves and underestimate our opponents, and Barnum effect is generally referring to generic praise that could apply to just about anybody, not necessarily you.