Have you ever heard of the Barnum effect? You have probably experienced it at some point in your life. The Barnum effect, also known as the Forer effect or Forer’s fallacy, is a term intended to describe the apparent accuracy of a personality description that is applied to a large group. 

It can be seen as exposing confirmation bias in people who apply such descriptions to themselves since accurate descriptions would imply that they are excellent judges of character. This article will discuss the Barnum effect and how to manage it.

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What is the Barnum Effect?

The Barnum effect also referred to as the Forer effect, is defined as a high level of agreement among individuals who give personality tests and interpret their results. This effect is named after the American showman and popularizer of the word “psychology”, Phineas T. Barnum.  

The Barnum effect has been shown in psychological assessments such as the Myers-Briggs Type Indicator, Jungian tests, and astrological readings. The Barnum effect is an assertion that “a great part of the effect comes from the attention which is paid to [a medium]”. 

The term was coined by psychologist Bertram R. Forer in a demonstration he performed in 1949. Forer asked participants to construct personality profiles for each member of a group, using only personality-related questions, and without revealing the purpose of the study. 

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The actual aim of the study was simply for Forer to compile some personality profiles on his students. All participants produced similar (and generally positive) personality profiles for each person, despite their only source being the same set of questions.

For example, have you ever used the phrase: “That’s so true for everyone!” You didn’t actually mean every single person, did you? It’s what we describe as playing on the Barnum effect, after showman P.T. Barnum who said “there’s a sucker born every minute.” The point is that it doesn’t matter if you’re trying to sell products or services, if it seems like it’s universally true, people assume they’ll be the one in a unique position to prove its validity.

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The Discovery of the Barnum Effect

The Barnum Effect was discovered by psychologist and author Dr. Forer in 1948 when he asked his students to fill out a personality test and then told them he would give them a personality analysis based on the results of their tests. After giving each student one, he asked them to rate it on a scale of 0-5 (0 being accurate and 5 being inaccurate).

On average, the students rated their analysis as 4.26 (out of 5). However, what they didn’t know was that each student received the exact same report. The report consisted of generic statements that could apply to anyone such as “You have a need for other people to like and admire you, and yet you tend to be critical of yourself.”

However, the Barnum effect term was coined by a psychologist named Paul Meehl in the 1950s. He had a theory that people would accept personality descriptions of themselves as true, even if those descriptions were vague, and could apply equally well to almost anyone.

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In order to test his theory, Meehl created three different types of personality descriptions that he gave to a group of college students:

• An extremely detailed description based on a questionnaire
• A vague description that could apply to almost anyone
• A random list of words with no particular meaning

Meehl found that the students rated the detailed profiles as more accurate than the vague ones and both of those as more accurate than the random lists. This effect has been studied extensively since then, and researchers have found that it can be applied to many types of psychological assessments. 

For example, people will believe that a horoscope is specific to them if it has enough general details in it. They will also rate personality tests highly if they are given enough choices and if those choices are general enough that they don’t feel like they’re being boxed into just one answer type. Researchers have also found that many people exhibit what they call “illusions of control.” Essentially, people think they can make things

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Barnum Statements

This effect, named for the infamous showman P. T. Barnum, refers to descriptions that seem very personal, but that is actually so vague that they could describe almost anyone! A common example of this phenomenon is found in fortune cookies. 

The fortune you get may be very specific and personal, but have you ever stopped to consider how many other people received the same one? The Barnum Statements are so effective because they’re based on flattery and they are designed to make you feel like they were written just for you.

Have you ever looked at your horoscope and thought: oh, no, that’s so not me? Maybe you’ve thought about your zodiac sign and been like, “That’s totally me” the Barnum effect is what causes those reactions.

The feeling that a statement is particularly applicable to you. And it works like this: the more positive a statement is, the more likely you are to accept it as true for you personally. So if you read out your horoscope and it says “Your life will be full of wonderful surprises today”, you are much more likely to believe it than if it said, “Your day will be full of terrible challenges”.

How to Manage the Barnum Effect

The best way to manage the Barnum Effect is to know it exists and be aware of it. This awareness helps you control your response to the situation. 

As you become more familiar with the Barnum Effect, you’ll realize that most people are vulnerable to it, and won’t judge you for falling victim. Also, you can use this knowledge of human psychology to better understand your customers and make your communications more effective.

Read: Simpson’s Paradox & How to Avoid it in Experimental Research

What Causes the Barnum Effect?

There are two main reasons for the Barnum effect and they are:

1. People want to believe that the things they hear about themselves are true, so they’re more likely to believe them.
2. People also tend to fill in the blanks when they don’t have enough information, so they’re more likely to interpret vague statements as being true for themselves.

Working Principles of Barnum Effect

1. Pollyanna Principle

Pollyanna Principle refers to people’s tendency to interpret ambiguous information in a positive light. It was named after Pollyanna, a character from Eleanor Porter’s 1913 novel who always looked on the bright side of things. Just as with the Barnum Effect, people may interpret vague descriptions in such a way that they become applicable to themselves. The theory behind this tendency is that people want to believe good things about themselves.

For example, if someone reads that they have an “enthusiastic and friendly personality,” they will likely agree with the statement because it’s positive and sounds like a good thing to feel about yourself.

This concept was illustrated by P.T. Barnum, who once said “We’ve got something for everyone.” This quote refers to how there is something for everyone at his circus and it also refers to how there is something for everyone in the idea of the Barnum effect.

2. Preference for Relatability

People like to see traits in themselves that they have seen in other people. If a trait has been observed in others, it is likely that the reader has that same trait. When people encounter information that feels relevant to their lives, they are more likely to believe it’s true.

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This is especially true when the information seems specific and personalized. For example, “You have a problem with authority” sounds much more applicable than simply “You have a problem.” This is why horoscopes are so popular: they are highly personalized and make statements

3. Preference for Likeability

Since people like to see themselves in a positive light, they prefer to see traits that are desirable and avoid seeing traits that are undesirable.

Barnum Statements Examples & Implications

• On personality tests and surveys

“You are a very logical person. You tend to think things through before acting. You enjoy having a structure in your life, and you like knowing exactly what’s going to happen next and when. You’re not particularly adventurous and you prefer keeping things nice and predictable.”

On the surface, this statement may seem like it applies specifically to you but it doesn’t actually say anything about you at all. It could apply to anyone who fits that description.

Personality tests like the Myers-Briggs Type Indicator (MBTI) are designed to categorize people according to their traits on a spectrum, from introverted/extroverted to thinking/feeling, among other factors. The test is designed so that most people score in the middle on all traits.

That means that when a person reads their results and finds out they are an INFJ or ENFP or any of the 16 possible combinations, they think that is an accurate description of who they are. However, since most people have a middle score on each trait, the results could actually apply to most anyone.

• On social media

Social media has become a place where people can post information about themselves that makes them appear attractive to others. Statements such as “You are a very colorful person, you can be highly critical of yourself, you feel that others are watching you and judging you all the time, you tend to avoid conflict.”

People are likely to believe the information posted about them because it speaks to their ideal self-image. This tendency can be used in marketing by companies when describing their products and services, which are then perceived as being more attractive than they actually are.

On social media websites like Facebook or Twitter, you may often be asked to fill out the information about yourself when creating an account so that they can personalize advertisements and content suggestions based on what they think you will like. 

While this information may not be as specific as your birthdate or home address, it’s still enough for advertisers to target you with ads that seem like they’re meant just for you.

Read: Survey Errors To Avoid: Types, Sources, Examples, Mitigation

• On intelligence tests

For example, on intelligence tests and online quizzes, people are sometimes asked to rate the accuracy of a statement like this one: “You often find yourself feeling misunderstood by others.” Almost everyone rates this as true, and it’s hard to imagine anyone rating it as false, because who doesn’t feel misunderstood from time to time? This is an example of the Barnum effect in action.

• On astrology

In astrology, for example, people tend to believe that the vague predictions in horoscopes are accurate because it’s easy to identify with ambiguous statements about who you are and how you behave. Because of the Barnum Effect, astrology and other forms of pseudo-psychology tend to be popular even though there’s no real evidence of any psychic ability. Many people are willing to simply accept that these methods work because they want them to work and because they accept personal descriptions as proof that these things are true.

• On palm reading and horoscopes

In palm reading, vague statements about your past and future such as “you have been through difficult times” still seem like they apply specifically to you because they’re so universal and broad. Also, Barnum statements are most commonly used by fortune-tellers and palm readers, who can make a prediction seem personal and meaningful to any individual, regardless of whether the statement is actually true or not.

For example, if a palm reader says “You’re very independent” or “You have an old soul,” these statements could apply to anyone. However, they may be interpreted by an individual as meaning something specific about him or herself.

Examples of the Barnum Effect

Some examples of the Barnum effect include horoscopes, fortune-telling, personality tests, and “cold readings,” which are when someone makes vague statements about a person and finds ways to credit their accuracy when the person agrees.

1. A horoscope will include a prediction for each sign of the zodiac that can apply to anyone who reads it; however, people tend to believe it is specific advice based on their individual sign.
2. Fortune cookies have become a tradition at Chinese restaurants in the United States, but they aren’t actually used in China. The messages inside are very broad and simple, but they can apply to anyone who reads them for example, “You will meet someone new soon,” “Your life will be full of good things,” or “You have a great future ahead of you.”
3. Personality tests such as the infamous Myers-Briggs test are also often subject to the Barnum effect because they are written in such general terms that they can apply to just about anyone however, people tend to believe that the results are specific and accurate for them.

How to Avoid the Barnum Effect

To avoid the Barnum effect, you should be skeptical when you read generic statements. If you hear something that is vague but positive, think about how it could apply to many different people.

Also, try to determine what information isn’t being shared. If a statement appears to be tailored for you but doesn’t give any specifics about your life or personality, there’s a good chance it’s not as accurate as it seems.

Think critically about what someone says. Don’t just say “Oh yeah!” or “That’s true!” Try to identify whether they’re making an accurate statement or using loaded language. Also, ask questions if something doesn’t make sense to you

Conclusion

One of the most common ways that people get duped by the Barnum effect is by believing things that are presented as personalized but are actually vague and applicable to a large number of people. You can help avoid the Barnum effect by making sure that your interpretations of others’ behavior are specific and supported by evidence.