Talk:Barnum effect

Later Studies
I noticed a later section of the article that gave information on later studies. However, it was not immediately obvious which studies produced these conclusions. Anyone with an expertise on the subject care to add the references? &mdash; Ambush Commander (Talk) 20:38, 14 December 2005 (UTC)

Barnum or Forer?
As the term "Barnum effect" seems to be much more popular than "Forer effect" (e.g., 20.000 vs 600 results in Google and only 90 for the personal validation fallacy), we should perhaps consider changing the title of the article. In all cases, there should be more consistency in the use of the term throughout wikipedia. For example, the List of cognitive biases refers to Barner whereas Selective thinking refers to Forer. Dragice 09:59, 15 December 2005 (UTC)


 * Agreed. Daniel 13:38, 25 October 2006 (UTC)


 * If the article had more information, I'd agree. I teach my students about the Barnum effect. However, this article doesn't have much information. It's largely taken up by Forer's description. It needs more information, like outside sources referencing the Barnum effect, before we bother moving it. Doczilla 15:32, 25 October 2006 (UTC)


 * Six years later, the article alleges that "The Forer effect is more frequently referred to as The Barnum Effect." - even if it doesn't have much to say about Barnum, if it's agreed to be the WP:COMMONNAME for the effect, the article title should reflect that. --McGeddon (talk) 10:03, 3 December 2012 (UTC)
 * I'd be weakly opposed to moving the article to Barnum effect. We should make a determined effort to use particularly Reliable Sources when determining what name to use. I suspect that we'll find a balance of usage, between "forer effect", "barnum effect", "barnum statements", and fallacy of "personal validation" or "subjective validation". In the text of the article, we should make this clear, and give details as to the origin and overtones of each "name". Number of googlehits is insufficient, for this decision. –Quiddity (talk) 21:13, 4 December 2012 (UTC)

And why Barnum? The first paragraph says it is becuase he said they have something for everyone a later paragraph says that it is becuase ( the more logical and one I always heard) he said there was a sucker born every minute. Which is it? As written the article contradicts itself. 75.177.47.137 (talk) 05:53, 29 October 2009 (UTC)
 * It's not a contradiction if he was just famous for saying things like this in general.--173.238.223.80 (talk) 19:18, 3 October 2010 (UTC)

I would also ask why choose "Barnum effect" as the title of the article, if the effect in question was first decribed in science by Bertram Forer? Should we not honor Bertram Forer for his work on this subject? Theophilius (talk) 19:31, 23 September 2016 (UTC)


 * Wikipedia's naming policy is neutral and should not be influenced by a desire, however noble or well-intentioned, to honor an individual for their work. For better and for worse the "Barnum Effect" is by far the more common description, and thus, WP:COMMONNAME dictates we adhere to that - as has already been noted above. That's why earlier proposals to move the page failed. -- Katan gais (talk) 20:43, 23 September 2016 (UTC)

P. T. Barnum - a hoaxer, not a scam artist
Changed the reference to P. T. Barnum from "a notorious scam artist" to "a notorious hoaxer" - the former was simply untrue. If anyone needs further reading, see here. — Preceding unsigned comment added by 85.64.44.106 (talk) 14:18, 30 November 2012 (UTC)

Relation to Fortune Cookie Fortunes
Potentially slightly off topic but, er, these Forer Demonstration list things sound a lot like fortune cookie fortunes from the 1960s and perhaps even today -- the reason being readily apparent. Would anyone like to trace the relationship in the main article or the one for fortune cookies? FurnaldHall (talk) 08:31, 26 May 2016 (UTC)

Pronunciation
Is the first syllable long or short?
 * short. JoeSmack Talk 18:00, 9 July 2006 (UTC)

Wording regarding horoscopes
I changed the wording of the text under the "Horoscopes" heading for clarity. The sentence, I presume, is referring to horoscope interpretations often done in printed publications like newspapers and the like. The horoscope article, on the other hand, focuses almost entirely on the diagram of the same name. It seems, therefore, inconsistent to say that there are perceived predictive powers in newspaper horoscopes when the linked article is about something entirely different, which is why I felt it better to distinguish between the two. Sam 22:09, 3 January 2007 (UTC)
 * So does that make sense? Sam 17:41, 4 January 2007 (UTC)


 * Well... in common usage, "horoscope" refers to those bits in newspapers in which astrological predictions are made. In other words, what the sentence is saying is: 'horoscopes are popular in the media because people are fooled by the Forer effect'. In view of this, "interpretations" doesn't fit well IMO. I take your point about wikilinking to horoscope though - perhaps we should leave it unlinked? Or link to Wikitionary? Mi kk er (...) 02:13, 5 January 2007 (UTC)

Right, but I don't think we should assume our audience does not include specialists who will cast a doubtful eye at such a generalization. A horoscope (that is, the diagram) is the very basis of what is considered "real" astrology (as opposed to the simple "horoscopes" in newspapers) and as such, I think a distinction should be made. One is a diagram that does not inherently claim anything: it merely is a map of celestial bodies and other points. The "horoscope" in common usage is the one claiming to have predictive power. Sam 17:50, 5 January 2007 (UTC)
 * I realize this is a lot of wind for such a small thing. If no one else has any thoughts I'll just drop it. Sam 17:17, 15 January 2007 (UTC)

I recall...
Rather than write in something that I can't immediately validate. I do however recall reading about "Cold Reading" (which makes "good" use of the Forer Effect) where it says that people are generally more likely to accept negative criticism as accurate in relation to how authoritive the presentor is.

That is, if it's just some random person, they're significantly more likely to discredit negative information immediately. But if you say that it's a computer program designed by a team of Ph.D.s that is infallible, they're much more likely to accept negative information.

So, I'm thinking of wording the "as long as most of the information is positive" in the variables for effectiveness to something similar to "as long as there is a high amount of positive information or perceived authority in the process." --Puellanivis 00:24, 15 March 2007 (UTC)

What were Forer's students rating?
As it's written now, there's no evidence that Forer's students exhibited the Forer effect. If they were merely asked to rate how well the 'analysis' applied to them, OF COURSE they gave it a high rating -- it really is an excellent description of what it means to be a human being. But there's no evidence in the article that any of the students was duped into thinking that the statement was specifically TAILORED for him/her as opposed to others. Doops | talk 05:00, 26 March 2007 (UTC)

In the article it says the teacher gave a personality test beforehand and then gave them the exact same description, so they were duped. Tissueissue 23:55, 16 April 2007 (UTC) Tissueissue

indi Hmm, I was thinking the same thing as Doops. If the test was conducted the way its explained here, it realy doesnt prove anything. Most people would rate that analysis 4 or 5 but it doesnt say whether they thought it singled them out from other people? --Apis O-tang 01:46, 23 July 2007 (UTC)


 * I was wondering the same thing. Technically Forer asked them to rate their results for accuracy, but just how specific he was about what that means we can't know. What about the original study- has anybody here read it? (There seem to be no online copies, which is understandable considering the year the thing was published, and whatnot). -AceMyth 04:41, 28 August 2007 (UTC)

The full text is here. The questions asked after giving the personality sketch to each student were:
 * A. Rate on a scale of zero (poor) to five (perfect) how effective the DIB is in revealing personality.
 * B. Rate on a scale of zero to five the degree to which the personality description reveals basic characteristics of your personality.
 * C. Then turn the paper again and check each statement as true or false about yourself or use a question mark if you cannot tell.

See tables 1 and 2 on page 9 for the results. Question C is clearly just about accuracy, but questions A and B are about the effectiveness of the method that was supposed to have produced the individual sketch to "reveal personality". If you read the whole paper and particularly the conclusions, it definitely avoids making the conflation suggested above -- although I agree that the current WP article is in danger of doing that. --David-Sarah Hopwood ⚥ (talk) 03:24, 6 December 2009 (UTC)

--FORER HOAX--

- - - I'm very sorry to have to demonstrate that that test was a complete hoax but i have to do it, so let me quickly explain some very little tricks that were used to drive it at the wished result and you will see with your own eyes why all this so accepted test was already a fake in the beginning.

To demonstrate this i just have to ask you to understand some basic astrological assumption like : to every one of the (12) sign, is given a specific print, regarging the way to act, personal expectation, and way to look other people.These prints are already known in the astrological community,but also a few between other people. So let's start : (reporting from the test)

1)"You have a great need for other people to like and admire you." Typical kind of people for astrology: Lion. Proud.Need of attention. 2)"You have a tendency to be critical of yourself." Typical kind for astrology: Virgo. U can find it almost -everywhere-. 3)"While you have some personality weaknesses, you are generally able to compensate for them." ---> Lybra. need explanations? 4)"Your sexual adjustment has presented problems for you." ---> Scorpio. always refer to very hot-blooded people. 5)"Disciplined and self-controlled outside, you tend to be worrisome and insecure inside."---> usually refer to Capricorn type. 6)"You prefer a certain amount of change and variety and become dissatisfied when hemmed in by restrictions and limitations"---> need of freedom? Sagitter type, you can find it almost everywhere on the net. 7)"You pride yourself as an independent thinker and do not accept others' statements without satisfactory proof."--->Acquarius.Genius for definition. 8)"Some of your aspirations tend to be pretty unrealistic"---> the Cancer.The dreamer par excellence.Or pisces. 9)"Security is one of your major goals in life."---> Anyone says Taurus? 10)"At times you are extroverted, affable, sociable, while at other times you are introverted, wary, reserved"---> Gemini type? 11)"You have found it unwise to be too frank in revealing yourself to others". Pisces,or Cancer. 12)"Have a great deal of unused capacity which you have not turned to your advantage".--->The sacrifice of Aries.(Argonauts etc.)

So.

If you put, 12 kind of (already known..)personality, to a group of people, where everyone have a personal astrological chart, made by 11-12 planets, that at the time of birth were -at least- in some different astrological signs,(rarely they are ALL in one sign), OF COURSE YOU GET IT ! I WONDER THEY NOT SCORE 4.9 OUT OF 5 !

And as usual, if a person, between some topics, find maybe one or two that match with his personality, he will give a nice score, just for the feeling that "wow they really match me!" , isnt' it??

So this experiment does not demonstrate nothing at all ! It use astrology (WELL KNOWN!)-->assumption, to demonstrate that astrology doesn't work ??? open your eyes guys !

Ty so much. — Preceding unsigned comment added by 79.1.123.10 (talk) 00:59, 25 February 2012 (UTC)

Oh dear... 72.201.209.141 (talk) 06:27, 29 October 2012 (UTC)

Aunt Fanny Effect
I added "Aunt Fanny effect" to the list of names it is known by. I also created a page with that title and redirected it to this one.  Amit @  Talk  15:18, 22 December 2007 (UTC)

When adding a redirect, please always make sure to mention the corresponding terms in the article, and to explain the connection. Note in particular that the one concept need not match the other---or may even be antonymous. 88.77.144.69 (talk) 22:27, 23 November 2009 (UTC)

The autotest
I messaged the author of that site a few months ago, but it doesn't seem that he's gotten around to fixing it yet.

As it is, the autotest is deeply flawed, as it gives 1 point for very poor - meaning that even if you rank every statement as completely untrue, it will still claim that it was "20% correct". I suggested moving the points down by 1 for each rank, and he did agree with that, but again, it doesn't seem like he's gotten to fixing it.

I believe there should be some kind of note explaining to readers that the test is not truly representative of the experiment because of this flaw. Not even Mr. Lister's Koromon survived intact. 21:40, 12 February 2008 (UTC)

Tengen Toppa Gurren Lagann
This link is in the See Also section, but seems to have nothing to do with this page. Can anyone else see a reason to keep the link? MagiMaster (talk) 22:25, 13 July 2008 (UTC)

Religious Counselling?
Isn't religious counselling generally done on a one-on-one basis, where the local religious leader gets to know the members of his "flock" and help them individually? Regardless of whether religious counselling is actually helpful, I don't see how religious counselling utilizes the Barnum effect.--173.238.223.80 (talk) 19:18, 3 October 2010 (UTC)

Something's wrong...
It seems to me on first glance that Forer effect and Subjective validation should be merged. Forer's own term for what we're calling the Forer effect is the Fallacy of subjective validation. The definition of subjective validation in its own article contradicts the definition in this article. Do the sources really say that subjective validation is more general than the Forer effect? If so, the subjective validation article needs a fundamental change. If not, then there needs to be a merge. MartinPoulter (talk) 17:51, 13 October 2012 (UTC)


 * I agree something is wrong. I am still not sure what the difference is between subjective validation and confirmation bias. Reading the introduction to the latter, and also the one to wishful thinking makes me think it's a synonym for the first. Add to that the entries on self-deception, cognitive bias and, especially, illusory correlation and I think that, even if the concepts are, indeed, distinct, the difference is way too subtle.


 * I think subjective validation itself should be merged with confirmation bias. This article, however, can probably stand on its own, however short. 177.18.189.71 (talk) 17:15, 19 October 2012 (UTC)


 * These are all different facets of the same phenomenon. However: Confirmation bias (as a term) does not specifically apply to personal meaning or significance (as does subjective validation), and can apply to opinions on general matters as well. The Forer effect, in term, is a specific example of subjective validation, as are many psychological effects of a higher cognitive function. — Preceding unsigned comment added by 85.64.44.106 (talk) 14:30, 30 November 2012 (UTC)

To Do List for Editing
Studies to be examined regarding the Forer [Barnum] Effect:

-Claridge, G., Clark, K., Powney, E., & Hassan, E. (2008). Schizotypy and the barnum effect. Personality and Individual Differences, 44(2), 436-444. doi: http://dx.doi.org/10.1016/j.paid.2007.09.006

-Mason, O. J., & Budge, K. (2011). Schizotypy, self-referential thinking and the barnum effect. Journal of Behavior Therapy and Experimental Psychiatry, 42(2), 145-148. doi: http://dx.doi.org/10.1016/j.jbtep.2010.11.003

-MacDonald, D. J., & Standing, L. G. (2002). Does self-serving bias cancel the barnum effect? Social Behavior and Personality, 30(6), 625-630. doi: http://dx.doi.org/10.2224/sbp.2002.30.6.625

-Snyder, C. R., Shenkel, R. J., & Lowery, C. R. (1977). Acceptance of personality interpretations: The "barnum effect" and beyond. Journal of Consulting and Clinical Psychology, 45(1), 104-114. doi:http://dx.doi.org/10.1037/0022-006X.45.1.104

-Poškus, M. S. (2014). A new way of looking at the barnum effect and its links to personality traits in groups receiving different types of personality feedback. Psichologija, 50, 95–105. Retrieved from http://www.vu.lt/leidyba//dokumentai/zurnalai/PSICHOLOGIJA/Psichologija%202014%2050/95-1050.pdf (the theoretical model from the article is allready uploaded, but I can't make corrections to the Forer effect page, because I'm assumed to be biased) Mykolas Poskus (talk) 19:31, 21 January 2015 (UTC)

Each of the above studies will be examined to assess psychologists beliefs about the Barnum Effect today. I suggest, as has been suggested elsewhere, we add this analysis under a new heading titled "recent research."

Proposed New Headings or Points to be Examined:

ORIGIN - If this article is to be moved to "Barnum Effect" - this pdf (page 266) shows the first time that the phenomenon was referred to as the "Barnum Effect" -http://psycnet.apa.org/index.cfm?fa=fulltext.journal&jcode=amp&vol=11&issue=6&page=263&format=PDF

CROSS CULTURAL STUDIES - -Rogers, P., & Soule, J. (2009). Cross-cultural differences in the acceptance of barnum profiles supposedly derived from western versus chinese astrology. Journal of Cross-Cultural Psychology, 40(3), 381-399. doi:http://dx.doi.org/10.1177/0022022109332843

CONNECTION TO ASTROLOGY - Astrology is briefly mentioned in the intro and might be worth expanding upon. Research shows that people who believe in astrology are more likely to encounter the Barnum effect -Glick, P., Gottesman, D., & Jolton, J. (1989). The fault is not in the stars: Susceptibility of skeptics and believers in astrology to the barnum effect. Personality and Social Psychology Bulletin, 15(4), 572-583. doi:http://dx.doi.org/10.1177/0146167289154010 -Rogers, P., & Soule, J. (2009). Cross-cultural differences in the acceptance of barnum profiles supposedly derived from western versus chinese astrology. Journal of Cross-Cultural Psychology, 40(3), 381-399. doi:http://dx.doi.org/10.1177/0022022109332843 -Fichten, C. S., & Sunerton, B. (1983). Popular horoscopes and the "barnum effect.". Journal of Psychology: Interdisciplinary and Applied, 114(1), 123-134. Retrieved from http://search.proquest.com/docview/616850706?accountid=9673 — Preceding unsigned comment added by Dupontgu (talk • contribs) 21:02, 22 October 2012 (UTC) -Tobacyk, J., Milford, G., Springer, T., & Tobacyk, Z. (1988). Paranormal beliefs and the barnum effect. Journal of Personality Assessment, 52(4), 737-739. doi:http://dx.doi.org/10.1207/s15327752jpa5204_13

SEX/GENDER DIFFERENCES - There seems to be some contention here, but some studies have shown that there are differences in males/females are affected by the Barnum effect -Layne, C. (1998). Gender and the barnum effect: A reinterpretation of piper-terry and downey's results. Psychological Reports, 83(2), 608-610. doi:http://dx.doi.org/10.2466/PR0.83.6.608-610 -Piper-Terry, M., & Downey, J. L. (1998). Sex, gullibility and the barnum effect. Psychological Reports, 82(2), 571-576. doi:http://dx.doi.org/10.2466/PR0.82.2.571-576 -Handelsman, M. M., & McLain, J. (1988). The barnum effect in couples: Effects of intimacy, involvement, and sex on acceptance of generalized personality feedback. Journal of Clinical Psychology, 44(3), 430-434. doi:3.0.CO;2-V" TARGET="_blank">http://dx.doi.org/10.1002/1097-4679(198805)44:3<430::AID-JCLP2270440319>3.0.CO;2-V

FORER'S ORIGINAL STUDY - The majority of the article focuses on Forer's (1948) study. This section really only addresses a few parts of his study, and the Claridge, Clark, Powney, & Hassan (2008) study gives greater detail about Forer's work. The article also examines the Forer effect in relation to belief in astrology, and as mentioned above, the section on astrology could be worth expanding upon.

SELF-SERVING BIAS - The MacDonald & Standing (2002) article examines whether self-serving bias is an accurate explanation for the Forer effect. It critiques the work surrounding the effect, and hypothesizes that self-serving bias is powerful enough to cancel the usual Barnum effect.

CLEAR DEFINITION - The Definition as given could use rewording to make it clearer, and most parts of the article could uses sources to back up claims, or examples to make claims more concrete and coherent. We will add sources to the article to achieve this goal.

Your proposed additions look very comprehensive. I like your inclusion of this new "research" section. Make sure you link some of your ideas to other articles. Looking forward to you article! — Preceding unsigned comment added by Testaccountpy242 (talk • contribs) 15:12, 7 November 2012 (UTC)

Hi Tom! I really enjoyed reading your article. You have done a great job. However, there are some areas that you can improve.

Areas for improvement 1. You should proofread the article again. The information is very good but there are some typos. There are also some phrases that could be worded better. The first sentence drags on a bit. 2. Under your heading “in popular culture,” you could expand more. Also, you could expand more under the “Replicating the study” section. 3. Adding a picture would bright up the page. We also think you could use more examples throughout the article.

Strengths: 1. You do a great job of linking words or phrases to other pages. You also do a great job with citations and references. We also like how you listed other Wikipedia pages that are similar to your topic. 2. Overall the article has a lot of good information. The research looks valid and accurate, and we think the article is very organized and flows well. The headings and spacing make it easy to read. 3. We really like your section called “Recent Research.” We feel that these examples allow us to relate to the subject.

Sheridaa (talk)Abbey Sheridan —Preceding undated comment added 17:33, 19 November 2012 (UTC)
 * This To Do list is really good. I'd like to see these changes implemented. MartinPoulter (talk) 10:20, 18 January 2013 (UTC)

Merger proposal
I propose that Subjective validation be merged into Forer effect. They are the same thing. Even footnote number two says so in the Subjective validation article. Spannerjam 07:53, 20 October 2013 (UTC)

I'm not sure they're exactly the same thing, but I agree that they could be merged into one article, with Forer effect as a subcategory of Subjective validationKeadle (talk) 22:07, 5 December 2013 (UTC)

Spannerjam proposed it the wrong way and Keadle is right: If we agree to a merger, the only reasonable way is to put it under the headline of "Subjective validation", because this is the more general one. — Preceding unsigned comment added by 77.4.225.111 (talk) 07:59, 2 March 2014 (UTC)

There has been no research demonstrating "subjective validation"—this was a term used by Marks and Kammann in their book. It should be merged under this article. — Preceding unsigned comment added by 71.248.172.41 (talk) 18:18, 29 March 2014 (UTC)

Subjective validation is a cognitive bias, and this bias is often present in the Barnum effect. However, the Barnum effect occurs because of various biases and is influenced by a multitude of factors, so I propose either adding subjective validation as one of the factors influencing the Barnum effect, or leaving these two articles separate. Mykolas Simas Poškus 19:41, 21 January 2015 (UTC) — Preceding unsigned comment added by Mykolas Poskus (talk • contribs)


 * I agree with the above editor that there are enough reliable, secondary sources that mention the Forer effect (sometimes under the name Barnum effect) that there is warrant here for a stand-alone article. Subjective evaluation is a broader, and indeed closely related, topic, and it of course also warrants a stand-alone article. I'll look for more secondary sources to follow up on the suggestions shown on this talk page of primary research literature on the Forer effect. See the general reliable sources content guideline on why to prefer secondary sources, and especially see the specialized  content guideline on medicine-related articles, which fits very well for articles on psychology, for why secondary sources are the sources to look for as we collaborate in  fixing this article. Thanks for your comments. -- WeijiBaikeBianji (talk, how I edit) 20:00, 21 January 2015 (UTC)

Requested move 21 March 2015

 * The following is a closed discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review. No further edits should be made to this section. 

The result of the move request was: Moved per request Mike Cline (talk) 19:48, 29 March 2015 (UTC)

Forer effect → Barnum effect – "Barnum effect" is the commonly used name, as can be seen in the sources currently cited by this article, or discovered by some simple independent searching. groupuscule (talk) 19:26, 21 March 2015 (UTC)


 * After checking sources, I agree. Of course there would still be a redirect from "Forer effect" (the name under which I first learned about this issue). The Wikpedia article names policy suggests preferring the common name as the first criterion. Seeing that you are interested in this kind of issue are motivated to look up sources, I may ask your help in a while for another article rename. -- WeijiBaikeBianji (talk, how I edit) 19:37, 21 March 2015 (UTC)
 * OK, sounds good, any time. By the way: I think we could come up with a better explanation of why it's commonly called the Barnum effect. aloha, groupuscule (talk) 20:03, 21 March 2015 (UTC)


 * The above discussion is preserved as an archive of a requested move. Please do not modify it. Subsequent comments should be made in a new section on this talk page or in a move review. No further edits should be made to this section.

Copyright Violation
The section with the list from the Diagnostic Interest Blank is in violation of copyright. Rissa, Guild of Copy Editors (talk) 02:13, 7 January 2016 (UTC)
 * How so? It says he assembled it from an astrology book. Planetjanet (talk) 20:50, 21 December 2016 (UTC)

james the amazing randi
randi is a massive figure in this area (public education about trickery, including this specifically) and has been through most of the 20th century. i haven't got the time to start the work & do it all, but i figure mentioning it here might bootstrap randi references where needed. along with harry houdini and penn & teller & other figures who have sorta collectively formed pillars of a skepticism community. — Preceding unsigned comment added by 101.98.178.115 (talk) 21:53, 22 August 2020 (UTC)

Self-serving bias "canceling" the Barnum effect
I honestly have no idea what "Self-serving bias has been shown to cancel the Forer effect" means. From reading the section it seems that self-serving bias could be an explanatory factor for the Barnum effect, as the vague statements people tend to believe are usually positive, or at least not negative. I can't think of any way that it would "cancel" the Barnum effect, or what that would even mean. I read the abstract of the study that was used as a source and was left none the wiser. There's an unexplained gap between the description of the study and the conclusion. The self-serving bias article doesn't mention Barnum effect. I'd be glad if this section was clarified. 80.220.74.45 (talk) 12:31, 16 January 2021 (UTC)

"Well Effect" listed at Redirects for discussion
An editor has identified a potential problem with the redirect Well Effect and has thus listed it for discussion. This discussion will occur at Redirects for discussion/Log/2021 December 31 until a consensus is reached, and readers of this page are welcome to contribute to the discussion. Xurizuri (talk) 10:26, 31 December 2021 (UTC)

Review papers for use in the article
I've just cleaned out a lot of primary research papers from the article. A reliable source (by Wikipedia standards, not by academic standards) for supporting a scientific claim is generally going to be a review or meta-analysis article. To that end, here is a list of reviews (some of which are already used in the article):
 * (arguably a review prior to the description of the magician)
 * (examines a set of effects, one of which is the Barnum effect)
 * (arguably a review prior to the description of the magician)
 * (examines a set of effects, one of which is the Barnum effect)
 * (examines a set of effects, one of which is the Barnum effect)

Entries in reliable encyclopaedias can also be used:

--Xurizuri (talk) 13:00, 31 December 2021 (UTC)