Editing Barnum effect (section)

==Early research==
In 1947, psychologist Ross Stagner asked a number of personnel managers to take a personality test. After they had taken the test, Stagner, instead of responding with feedback based on their actual individual answers, presented each of them with generalized feedback that had no relation to their test answers but that was, instead, based on horoscopes, [[Graphology|graphological]] analyses, and the like. Each of the managers was then asked how accurate the assessment was. More than half described the assessment as accurate, and almost none described it as wrong.<ref name="Psychology Today">{{cite magazine |author=Adrian Furnham |title=We've Got Something for Everyone: The Barnum Effect |url=https://www.psychologytoday.com/blog/sideways-view/201411/weve-got-something-everyone-the-barnum-effect |magazine=Psychology Today |date=November 21, 2014 |access-date=February 25, 2017}}</ref><ref>{{cite journal |last=Stagner |first=Ross |date=September 1, 1958 |title=The Gullibility of Personnel Managers |journal=Personnel Psychology |volume=11 |issue=3 |pages=347–352 |doi=10.1111/j.1744-6570.1958.tb00022.x |issn=1744-6570}}</ref>

In 1948, in what has been described as a "classic experiment",<ref name="Denis Dutton">{{cite journal |last1=Dutton |first1=Denis |title=The Cold Reading Technique |url=http://www.denisdutton.com/cold_reading.htm |journal=Experientia |year=1988 |volume=44 |issue=4 |pages=326–332 |publisher=Denis Dutton |doi=10.1007/BF01961271 |pmid=3360083 |s2cid=2382430 |access-date=February 26, 2017 |archive-date=January 14, 2020 |archive-url=https://web.archive.org/web/20200114055246/http://www.denisdutton.com/cold_reading.htm |url-status=dead |url-access=subscription }}</ref> [[psychologist]] Forer gave a psychology test&nbsp;– his "Diagnostic Interest Blank"&nbsp;– to 39 of his psychology students, who were told that they would each receive a brief personality [[Vignette (psychology)|vignette]] based on their test results. One week later Forer gave each student a purportedly individualized vignette and asked each of them to rate it on how well it applied. In reality, each student received the same vignette, consisting of the following items:<ref name="Forer">{{cite journal |last=Forer |first=B. R. |author-link=Bertram Forer |date=1949 |title=The fallacy of personal validation: A classroom demonstration of gullibility |journal=Journal of Abnormal and Social Psychology |volume=44 |issue=1 |pages=118–123 |doi=10.1037/h0059240 |url=http://apsychoserver.psych.arizona.edu/JJBAReprints/PSYC621/Forer_The%20fallacy%20of%20personal%20validation_1949.pdf |pmid=18110193 |url-status=live |archive-url=https://web.archive.org/web/20160305220420/http://apsychoserver.psych.arizona.edu/JJBAReprints/PSYC621/Forer_The%20fallacy%20of%20personal%20validation_1949.pdf |archive-date=March 5, 2016 }}</ref>
{{quotation|
# 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.
# Your sexual adjustment has presented problems for you.
# 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 students rated its accuracy as 4.30 on a scale of 0 (very poor) to 5 (excellent). Only after the ratings were turned in, it was revealed that all students had received an identical vignette assembled by Forer from a newsstand astrology book.<ref name="Forer" /> 

Forer attributed the effect to [[gullibility]].<ref>{{cite web |url=http://psych.fullerton.edu/mbirnbaum/psych101/barnum_demo.htm |title=The Barnum Demonstration |website=Psych 101 Web Site for Introductory Psychology |author=Michael H. Birnbaum |publisher=CSUF Psychology Department |access-date=February 14, 2018}}</ref> The effect has been said to confirm the [[Pollyanna principle]], where individuals tend "to use or accept positive words of feedback more frequently than negative words of feedback".<ref name="Psychology Today"/>