Monday, May 5, 2014

The Forer Effect and the Flaw of Subjective Validation

I have been on a bit of a "What Star Wars / Harry Potter / Lord of the Rings / Character Are You?" jag lately. And I have attempted to justify this under the "Know Thyself" leadership imperative.

In a spirit of fairness and objectivity, I want to balance my recent foray into popular psychology with a look into the cognitive biases that make clinical psychologists look askew at astrology, numerology, tarot, graphology, feng shui, I Ching, psychics, hypnosis, faith healers, and even the "What color are you?" versions of the good old MBTI.

The term, "cognitive bias" refers to the inherent thinking errors that humans make in processing information. There are many, many forms of cognitive bias. Just kidding, there are exactly 88 named types of cognitive bias, What? You don't believe me? Look it up HERE. The one type of cognitive bias we are going to focus on is called Subjective Validation bias, which is--whoops! Not on the list. OK, there are 89 named types if cognitive bias....

I will explore this theme with the help of selected guest authors. Citations are provided in the references below.

Subjective Validation

Subjective validation, sometimes called personal validation effect, is a cognitive bias by which a person will consider a statement or another piece of information to be correct if it has any personal meaning or significance to them. In other words, a person whose opinion is affected by subjective validation will perceive two unrelated events (i.e., a coincidence) to be related because their personal belief demands that they be related.

Subjective Validation refers to a process by which people accept some claim or phenomenon as valid based solely upon a few personal experiences or subjective perceptions. In practice, this error is cited when a person perceives two independent events as having some sort of deeper, hidden relationship because of that person’s prior beliefs, expectations or hypotheses about the world.

In other words, this is why people so readily believe their horoscope.

The Forer Effect

The Forer effect (also called the Barnum effect after P. T. Barnum's observation that "we've got something for everyone") is the observation that individuals will give high accuracy ratings to descriptions of their personality that supposedly are tailored specifically for them, but are in fact vague and general enough to apply to a wide range of people. This effect can provide a partial explanation for the widespread acceptance of some beliefs and practices, such as astrology, fortune telling, graphology, and some types of personality test.

In 1948, psychologist Bertram R. Forer gave a personality test to his students. He told his students they were each receiving a unique personality analysis that was based on the test's results and to rate their analysis on a scale of 0 (very poor) to 5 (excellent) on how well it applied to themselves. In reality, each received the same analysis:

You have a great need for other people to like and admire you. You have a tendency to be critical of yourself. You have a great deal of unused capacity which you have not turned to your advantage. While you have some personality weaknesses, you are generally able to compensate for them. Disciplined and self-controlled outside, you tend to be worrisome and insecure inside. At times you have serious doubts as to whether you have made the right decision or done the right thing. You prefer a certain amount of change and variety and become dissatisfied when hemmed in by restrictions and limitations. You pride yourself as an independent thinker and do not accept others' statements without satisfactory proof. You have found it unwise to be too frank in revealing yourself to others. At times you are extroverted, affable, sociable, while at other times you are introverted, wary, reserved. Some of your aspirations tend to be pretty unrealistic. Security is one of your major goals in life.

On average, the rating was 4.26 of 5--over 85%. Only after the ratings were turned in was it revealed that each student had received identical copies assembled by Forer from various horoscopes. As can be seen from the profile, there are a number of statements that could apply equally to anyone.

In another study examining the Forer effect, students took the MMPI personality assessment and researchers evaluated their responses. The researchers wrote accurate evaluations of the students’ personalities, but gave the students both the accurate assessment and a fake assessment using vague generalities. Students were then asked to choose which personality assessment they believe was their own, actual assessment. More than half of the students (59%) chose the fake assessment as opposed to the real one.

The Barnum Effect
by Prof M. Birnbaum, Fullerton College

The Forer effect is also known as the "Barnum effect." This term was coined in 1956 by American psychologist Paul Meehl in his essay "Wanted – A Good Cookbook." He relates the vague personality descriptions used in certain "pseudo-successful" psychological tests to those given by entertainer and businessman P. T. Barnum, who was a notorious hoaxer.

The Barnum effect is named after P.T. Barnum, the showman who declared "there¹s a sucker born every minute." He found many ways to separate "suckers," as he called gullible people, from their money.

The Barnum effect in psychology refers to the gullibility of people when reading descriptions of themselves. By personality, we mean the ways in which people are different and unique. However, it is possible to give everyone the same description and people nevertheless rate the description as very very accurate.

Whenever I ran this in class, one student would invariably raise his or her hand and declare: "Well, I was right to rate it as very very accurate because you gave everyone MY description!" And the rest of the class would laugh because they all felt the same way.

This shows how easy it is to be fooled by psychics, quack psychotherapists, fake faith healers, and others who use this technique to make people think that they really know and understand them when in fact it is just a "Spiel" or "game, played as a prank." Magicians use a method called, "The Art of Cold Reading" to give people the impression of a very accurate psychic reading. This same method is used by quack psychics and others to separate the gullible from their money.

This same Barnum demonstration has been played on introductory psychology students for over 50 years (Forer, 1949), and for some reason, it never ends up in the public conscience, thanks to the systematic misrepresentation of psychology in the popular media. It even works with personnel managers, who should know this effect by training (Stagner, 1958). It is in our textbook by Kalat, and it should be described in all other Introductory Psychology books.

You might occasionally find a TV program featuring magicians who are exposing fakes, but you will rarely see a psychologist attacking the phony "radio and TV" psychologists who listen to a person for 30 seconds and then proceed to give them a phony diagnosis followed by a public dressing down on the air. Real psychologists are horrified by this practice, but there is money to be made by radio personalities, so that game goes on and on.

Now I run the test by a computerized personality test, and even have it programmed so that the skeptical person can take the test over and over, trying different answers to see what happens. Some of my students have learned to be skeptical and check it, but an amazing number continue to rate the description as very very accurate.

There are two kinds of magicians, the honorable kind and the unethical kind. The ethical magician admits that he or she uses tricks to create illusions. The unethical magicians use the same devices to claim to have magic powers. Magicians do not reveal how tricks performed by ethical magicians are done, in order to preserve the mystery. However magicians make an exception when unethical magicians use their methods to defraud and deceive. Harry Houdini, Amazing Randi, Penn and Teller, are examples of real magicians who reveal secrets to expose phonies, quacks and frauds who claim to have psychic powers, mind over matter, or to communicate with the dead.

The moral of the Barnum Demonstration: Self-validation is no validation. Do not be fooled by a psychic, quack psychotherapist, or a phony faith healer who uses this trick on you! Be skeptical and ask for proof. Keep your money in your wallet, your wallet in your pocket, and your hand on your wallet.

For me, the bottom line is this: I will still continue exploring my fascination with popular psychology. However, I will do so "with a grain of salt." Because we all know that

  • salt represents the value of skepticism, 
  • spilling the salt invites evil, and 
  • tossing a pinch of the spilled salt over the left shoulder temporarily blinds the evil spirit lurking there.

"A consciousness in which there lives the idea that spilling salt will be followed by some evil, obviously allied as it is to the consciousness of the savage, filled with beliefs in omens and charms, gives a home to other beliefs like those of the savage." --Herbert Spencer, 1875

"Know thyself, 
but believe thou not
everything thou readest!" 


Birnbaum, M., The Barnum Effect,

Forer, B. R. (1949). The fallacy of personal validation: A classroom demonstration of gullibility. Journal of Abnormal and Social Psychology, 44, 118-123.

Rational Wiki, List of Cognitive Biases,

SpencerHerbert The Study of Sociology (Appleton, 1875), ch. 1, "Our Need of it" , p. 5.

Stagner, R. (1958). The gullibility of personnel managers. Personnel Psychology, 11, 347-352.

Wikipedia, Subjective Validation,

Wikipedia, The Forer Effect,