What Warren Buffett said about IQ, traced to the record

0 The short answer

Warren Buffett has never published an IQ score, and no test result for him appears in any source searched here, so every single number attached to his name is an estimate with no source. What he did say, repeatedly and on the record for decades, is that investing does not need a high IQ: he put the level at 125 in 2005 and 150 in 2009, and he named 160 in a 2011 interview, each time telling an audience that the points above a modest level can be thrown away or sold. The best known version, the guy with the 160 IQ who does not beat the guy with the 130 IQ, is printed in a 1997 book, and its occasion could not be found in the transcripts searched. Read these remarks as one practitioner's opinion about temperament, not as a measured result and not as evidence of his own score.

1 Has Warren Buffett ever given an IQ number for himself?

No source searched for this page contains an IQ score for Warren Buffett, from a test or from his own mouth, and the places most likely to hold one were searched in full. The searched material was the Berkshire Hathaway annual meeting transcripts in the CNBC Warren Buffett Archive (the session transcripts for 1994 to 2020 and 2022 to 2024 that carry text), and all 48 of his letters to shareholders posted on Berkshire's letters page for 1977 to 2024. The words IQ or I.Q. occur dozens of times in the transcripts and in two of the letters. Not one occurrence reports a score for him.

Two passages come closest, and neither is a number. At the 2015 meeting his partner Charlie Munger joked that Buffett got by with a "horrible deficit of IQ" compared with Henry Singleton of Teledyne, whom Munger called much smarter than either of them, and Buffett cut in to ask that they not quantify it (2015 morning session). In 2022 he described his younger self as someone who was "intensely interested" in stocks, who "had a decent IQ" and who read and thought about them for years before one paragraph in Benjamin Graham's book changed how he looked at them (2022 morning session). A qualitative self-description of that kind cannot be converted into a score on any scale.

The absence is a finding about these sources, not a proof about the world. A private school record or an employer screening could exist and be unpublished. What can be said is narrower: no such document has been cited by anyone this review could find, and the pages that print a figure give no test, date or examiner. A claim about a person's IQ needs the same three details as any other measurement. Without them, a figure is a claim with nothing behind it.

2 Where do the figures attached to his name come from?

The figures that circulate for Buffett are either unsourced estimates or misreadings of his own rhetorical numbers, and none of them names a test. Searching for his IQ returns pages that list 150, 155 or "over 150", and others that say he needs only 130. Each was opened on October 6, 2026, and the basis it states is reproduced below, because the basis is what decides whether a figure is evidence.

The CNBC article is worth reading closely, because it is where many readers meet the 130. It reports that Buffett says there is a specific IQ score you need to succeed, 130, and it supports that with the quotation from the book Warren Buffett Speaks. The quotation compares two people, one with a 160 IQ and one with a 130 IQ. It does not name 130 as a requirement. In the meeting transcripts he named 125 in 2005 and 150 in 2009. The 130 in the article is the reporter's gloss, and the next sections show why a single required score does not fit anything he said.

ACIS has covered other business figures the same way. The pages on Bill Gates, Steve Jobs and Jeff Bezos each examine where a circulating number for that founder came from. Buffett differs in one respect. For those founders a number circulates and the question is its origin. For Buffett no number has an origin to find, and the documented material is a set of sentences about IQ numbers in general. The broader pages on celebrity IQ numbers and their sources and on why no highest IQ can be verified explain why that distinction matters.

3 What did Buffett say about IQ at Berkshire annual meetings?

Across 13 annual meetings between 1995 and 2022 Buffett used IQ as an illustration and never as a measurement, and the level he named moved from one occasion to the next. The Berkshire meetings are the best primary record because they run for hours, the questions come from shareholders and journalists, and CNBC publishes the transcripts session by session. The table lists the occasions that matter most. The wording is quoted only where it can be quoted without alteration, and otherwise summarized, because the transcripts are spoken language. Each year and session links to its transcript.

Three features of the table matter more than any single row. First, the cutoff moves. He said 125 in 2005 and 150 in 2009, and in other sessions he reached for 140 (2000), 160 (1998 and 2015) and 180 as round numbers. A man reporting a result does not change the result from year to year. A man using a figure of speech does.

Second, the high numbers are rhetorical. In the afternoon session of 2002 he said one does not need "a 200 IQ" to see a speculative period and work out how to move wealth from other people to oneself (2002 afternoon session). In 2012 he credited an understanding of how people behave for giving Berkshire an edge over people with "IQs of 180" who can do mathematics he could not (2012 afternoon session). The arithmetic later on this page, and the page on what an IQ of 160 means, show that 200 and 220 describe rarities beyond any real population, so those numbers work as figures of speech.

Third, he never says intelligence is irrelevant. In 2009 he said an investor needs to be reasonably intelligent. In 2005, in an answer about benefits for older people, he said that someone "wired with an I.Q. of 85" would not do remotely as well in a market economy as he and Charlie Munger do (2005 afternoon session). His claim is narrower than the slogan: above a modest level, extra points do not buy a decisive edge in one activity. The pages on IQ and success and IQ and job performance cover the general evidence that a slogan cannot settle.

4 What did he say about IQ in letters, lectures and interviews?

Outside the meetings Buffett's IQ remarks are scarcer and mostly confirm the meeting record, with one document, the 1998 Florida lecture, adding the clearest statement of what he thinks IQ is for. The letters hold the least. A search of the 48 letters posted for 1977 to 2024 finds IQ in only two. The letter for 2007, signed February 2008, uses a joke he attributes to Molly Ivins about a politician's IQ to describe his own lapse in turning down a television station purchase. The letter for 2016, signed February 25, 2017, uses IQ twice. In one place he repeats a line from Munger that it is great to have a manager with a 160 IQ unless the manager thinks the number is 180. In another, in a passage comparing index funds with funds of hedge funds, he writes that smart people run hedge funds but their efforts are largely self-neutralizing and "their IQ will not overcome the costs they impose on investors." Neither letter gives a number for himself.

The 1998 lecture is richer. On October 15, 1998 he spoke to MBA students at the University of Florida, and a transcript is hosted by Tilson Funds. He opened by telling the students that they all had "the IQ to do well", but that success depends on more than intellect and energy. He then asked them to imagine buying 10 percent of one classmate's lifetime earnings and posed the question "Will you give them an IQ test and pick the one with the highest IQ?" before answering "I doubt it." The qualities he listed instead, leadership, honesty and generosity, he described as behavior, temperament and character that anyone in the room could achieve. Later in the same lecture he said 16 of the senior people at Long-Term Capital Management had about as high an IQ as any 16 people working together in one business in the country, and that risking what you have and need for something you do not need is foolish regardless of IQ. The transcript's provenance is a limit. Tilson Funds hosts it as a PDF, and the document does not say who produced the text.

Two interviews fill in the rest. In 1985 he told the television host George Goodman that one needs enough IQ "to get from here to downtown Omaha" but not the ability to play "three-dimensional chess", and that the work needs a stable personality. That wording is taken from a CNBC report on the interview published September 22, 2019, not from the broadcast, which this review did not see. In 2011, in an interview in India, an audience member asked whether his success came from intelligence or discipline. According to a transcript on Farnam Street, which this review read but whose video it did not view, he said an investor with a 160 IQ should "sell 30 points to somebody else", that the right temperament is what matters, that "the 160s" will not necessarily beat "the 130s", and that they "do not have a big edge." That interview is the occasion where 160, rather than 150, appears in the sell-the-points version.

Finally, there is a magazine compilation. BusinessWeek Online of July 5, 1999 printed a page of Buffett sayings edited by Amey Stone, drawn from reporter Anthony Bianco's notes of private conversations, speaking engagements and press conferences during four days beside him. Those are notes, not transcripts, so the wording is the reporter's record of what was said. The page matters for two reasons covered next: it contains a sentence about ordinary intelligence and temperament that later gets spliced into the famous line, and it records his remark that he "won the ovarian lottery".

5 Is the line about the 160 IQ and the 130 IQ a real quotation?

The sentence about the guy with the 160 IQ and the guy with the 130 IQ is printed in a 1997 book as Buffett's, but its occasion is not shown in any text this review could read, and the form most pages repeat is a splice of two different sources. The sentence is "Investing is not a game where the guy with the 160 IQ beats the guy with a 130 IQ. Rationality is essential." It appears more than once in Janet Lowe's Warren Buffett Speaks, published by John Wiley in 1997. This review could read only search snippets of the Internet Archive's lendable copy. Those snippets show the sentence and its endnote markers, and they show that the book's endnotes cite sources such as Berkshire annual meetings and Outstanding Investor Digest, but they did not show the note for this line.

The transcripts do not repair that gap. The CNBC transcripts of the 1994, 1995 and 1996 meetings, the three before the book's publication, contain no sentence pairing a 160 IQ with a 130 IQ. The phrase "160 IQs" appears in the 1998 and 2015 sessions, but in other contexts: first about people who built the year 2000 problem, and later about dysfunctional people Buffett and Munger had met. So the line may come from an interview, a talk or a paraphrase. As worded, no source located here shows him saying it.

The version most readers see adds a second sentence. It reads "Once you have ordinary intelligence, what you need is the temperament to control the urges that get other people into trouble in investing." That sentence comes from the BusinessWeek compilation of 1999, where it follows a different sentence, that success in investing does not correlate with IQ above a certain level. The archived page prints that level as 25, which is almost certainly a dropped digit, because later reprints give 125 and Buffett used 125 at the 2005 meeting. Pages that join the 1997 sentence to the 1999 sentence, such as the Farnam Street page on temperament, print a composite that appears in neither source.

The last two rows show how the confusion can grow. At the 2009 meeting Munger, in the same session where Buffett said to sell 30 points, remarked that thinking your IQ is 160 when it is 150 is a disaster, and that a 130 who operates well within himself is much better. This review does not claim those remarks created the 160 versus 130 pairing, since the book of 1997 came first. They show how easily different speakers' numbers get stirred into one quotation.

The accurate summary is short. The idea is Buffett's, and his 2011 remark about "the 160s" and "the 130s" is a softer, transcribed form of it. The exact sentence is attributed to him in a 1997 compilation. The composite is not a quotation. Anyone citing the line should name Lowe's book and say its occasion is unknown.

6 What does he say matters more than IQ, and what does he say he does not know?

Buffett names temperament, rationality, realism and discipline as what matters in investing, and he says in his own words that he does not know whether that temperament is born or learned. The terms change from year to year, so it helps to collect them. In 2002 he called "realism and discipline" the important thing. In 2004 he said "the temperament is all important" and that "it does require extraordinary discipline". In 2009 he asked for "emotional stability" and "inner peace" about one's decisions, plus the ability to "think for yourself". In 2016 he put it as "emotional control". In 2011 he described the needed trait as the ability to detach from other people's opinions and to look at the facts of a business unaffected by what others think. These are one idea described several ways: the capacity to act on your own reading of the facts when a crowd, or your own mood, pulls the other way.

The origin of that capacity is where his answers become cautious. In 2002 an audience member argued that great investors are made, not born. Buffett largely agreed, but about the detachment itself he said he did not know to what extent it is innate and to what extent it is learned, and that certain matters of temperament "may be innate" and "may be learned" and may be intensified by experience (2002 morning session). In 2009 he repeated that he did not know how much of it is innate and how much can be taught (2009 morning session). A reader who takes the slogan that temperament beats IQ as a settled finding is therefore ahead of the man who said it.

What he does claim about learning is specific and biographical. In the same 2002 answer he said that from age 11 to 19 he read every investing book he could find and did not do well at all, and that reading Benjamin Graham's book in 1949 at the University of Nebraska changed his view of investing. He offered that as evidence that he learned his approach and was not simply born with it, and the transcript records "the proof is in my record" as his own words. That is testimony about one person's path. It is not a comparison group, and he did not claim it was.

He also describes a mental skill that is separate from general ability, which he calls a "money mind". In 2004 he attributed the phrase "money mind" to the investor Phil Carret and said he would call it a business mind. In 2017 he said people can have "120 IQs or 140 IQs" and similar scores on intelligence tests, yet some have minds good at one kind of thing and some at another, and that he has known very bright people who do not have money minds and make unintelligent decisions (2017 morning session). In 2019 he said the same thing about specialties: some people have what he calls a "money mind" and this is not mainly a question of IQ (2019 afternoon session). Our reading is that he is reaching for the distinction between general ability and narrower abilities, which the page on the CHC model explains.

Three limits keep the section honest. First, Buffett is reporting what he and Munger have seen. The sample is the people they have worked with and watched, and he does not claim a count or a comparison. Second, temperament as he uses it is not the construct that research calls emotional intelligence, which the page on emotional intelligence versus IQ treats separately, and it is not the same as the personality traits that correlate with IQ. Third, the word wisdom, which he also uses in 2020, is a different idea again, covered on the page on intelligence versus wisdom. This page recommends no investment method and takes no view on any of them.

7 What do an IQ of 130 and an IQ of 160 mean on the standard scale?

On a scale with a mean of 100 and a standard deviation of 15, an IQ of 130 is reached by about 1 person in 44 and an IQ of 160 by about 1 in 31,574, while the 200 and 220 he used in passing describe rarities beyond any real population. The table is our arithmetic on the normal curve, not a statistic from any test or from any study of Buffett. The gap between a 130 and a 160 is 30 points, or two standard deviations, which is why the quotation is a strong claim and not a trivial one.

Read down the last column and the pattern is plain. His 1998 comparison used 80, 100 and 140, which sit where the scale is well populated, and 125 and 130 correspond to roughly the top 5 and the top 2 percent. By 160 the arithmetic puts a person at about 1 in 31,574. By 200 the normal curve gives about 1 in 76 billion, a rarity larger than the present world population, so a "200 IQ" or a "220 IQ" is a way of saying very bright and not a measurement. That is how Buffett used them.

Two cautions apply. The normal curve is an assumption, and the real tails of IQ distributions depart from it, so a figure such as 1 in 31,574 is the output of a model and not a headcount. Also, whether a given test can report a score as high as 160 depends on that test's own norms, a question the manual of each instrument answers. The pages on the standard deviation of 15, on how IQ scores are normed and on the IQ percentile calculator explain the scale, and the page on what an IQ of 130 means covers the band he used as his lower comparison.

8 Why does a market change what an IQ gap is worth?

A remark about a 130 and a 160 compares people who have already passed through selection and who compete with each other, and in that setting the link between IQ and results can look weak even when IQ matters in the wider population. Two separate ideas are folded into the sentence, and Buffett supplied both himself.

The first is competition. In 1998 he posed a thought experiment: if 500 cloned copies of Jack Welch ran every Fortune 500 company, would returns on equity for American business be higher? He suggested not necessarily, because of "a self-neutralizing effect", like 500 expert chess players in one tournament, where there are still many losers. He drew the lesson for securities markets: it is far better to have a hundred IQ when everyone else has an 80 than 140 when everyone else has 140. His 2016 letter makes the same argument with arithmetic. Active investors as a group hold about what the whole market holds, so before costs they must do about average, and after fees and trading costs they do worse than passive holders. He writes that the smart people running hedge funds largely cancel one another out, so that "their IQ will not overcome the costs they impose on investors." This is a claim about the aggregate of a zero-sum contest. It does not say individuals never beat the average, and it does not say IQ is useless. It says the edge in a contest is a difference between you and the other players, not your level.

The second idea is selection, and it is statistical. A well-known problem, set out in a typology of range restriction by Sackett and Yang in 2000, is estimating the population correlation between two variables from a sample restricted by some selection process. When everyone in the room has been selected on a trait, the correlation measured inside the room is not the correlation in the population, and methods for correcting it exist for that reason. Investment professionals, MBA students and fund managers are selected groups. Buffett's 2002 observation that he saw "relatively little correlation between investment results and IQ" came from such a group, and he did not claim a count. A weak relationship inside a selected group can reflect the restriction itself and not the strength of the underlying relationship.

Neither idea proves or refutes the quotation. They explain why it may be true as a statement about professionals and still say nothing about the relationship between IQ and income or occupation across a whole population, which is the subject of the pages on IQ and income and on IQ and job performance. They also explain why no single study can confirm a comparison between two named IQ levels in one profession: the groups needed, people at 130 and at 160 doing the same job, are rare, and the outcomes are comparative by construction.

9 What do studies of investors with measured IQ find?

The nearest studies find that higher measured ability goes with better investing outcomes on several measures, which neither confirms nor contradicts a claim about the gap between a 130 and a 160 among professionals. They are worth reading because they come closest to testing the quotation. All three are observational, and each has a feature that limits what it can say.

Three readings follow. The first is that the population-level link is positive on these outcomes. The 2011 authors report the pattern after controls and with sibling comparisons that they argue address omitted family factors, though sibling designs do not make a study experimental. The second is that Chevalier and Ellison's own abstract is a lesson in caution: most of the raw differences between managers could be explained by behavioral differences and selection biases, and the difference that survives concerns the average SAT of a school.

The third reading is the one that matters for the quotation. Nothing in these studies compares a 130 with a 160 inside one profession, and nothing in them measures the temperament Buffett describes. They are consistent with a world in which IQ helps on average and extra points above a threshold add little, and they are consistent with a world in which it keeps helping. Buffett's claim, the studies, and the selection logic of the previous section are about different comparisons. The pages on IQ and income and on IQ and success cover how large the general associations are, and why a group result is not a forecast for one person.

10 Is rationality the same thing as IQ?

Cognitive psychology supports the narrow form of Buffett's point, that many thinking biases are unrelated to measured cognitive ability, without supporting the broad form, that ability does not matter. In 2008 Stanovich and West reported seven studies in which a large number of thinking biases were uncorrelated with cognitive ability (Journal of Personality and Social Psychology, 2008). The list includes the conjunction effect, framing effects, anchoring effects, outcome bias, base-rate neglect, myside bias and the sunk-cost effect. In a further experiment they found that cognitive ability did correlate with avoiding some other biases: denominator neglect, probability matching, belief bias and matching bias on the four-card selection task. They then offered a framework for predicting when ability will and will not correlate with a rational thinking tendency.

Buffett's remark of 2020 that IQ "does not always translate into rationality and behavioral success or wisdom" fits the first half of that result. So does a recurring example of his, the senior people at Long-Term Capital Management. In the 1998 Florida lecture he said they had "a great reliance on mathematics", and in 2019 he said he and Munger had seen "really extraordinarily high-IQ people" destroyed by leverage (2019 morning session). That is one episode told by one observer, and the explanation, leverage and over-reliance on models, is his own reading.

Two gaps remain. The experiments measure performance on reasoning tasks, not the steadiness under social pressure that Buffett calls temperament, and nothing cited here measures that. The second gap is that biases unrelated to ability leave room for ability to matter elsewhere, and the second result of Stanovich and West points the same way. Standard IQ batteries sample abilities such as fluid reasoning (Gf), crystallized knowledge (Gc), working memory (Gwm), visual processing (Gv), quantitative knowledge (Gq) and processing speed (Gs), and they were not built to measure temperament. The page on what IQ measures lists those abilities, and the pages on critical thinking versus intelligence and on the cognitive reflection test show how rationality-style tasks differ from the items of an IQ battery.

11 What does the documented record show, and what can it not show?

The record documents a long and specific career and some early history in his own words, and none of it can be converted into a score without assumptions the record does not contain. The table sorts the main biographical claims by who documents them.

The company figures are a record. The early history is memory told decades later, and it is consistent across the 1998, 2002 and 2005 tellings without being independently confirmed here. Three things the record cannot show matter more than what it can. First, it cannot separate skill from capital and time. A gain compounded over six decades reflects duration as well as skill, and the table's last figures are the product of both. Second, it cannot separate skill from luck, and Buffett does not try. In 1999 he said he "won the ovarian lottery", and in the 1998 Florida lecture he described that lottery as deciding things like being born in the United States or Afghanistan and "born with an IQ of 130 or an IQ of 70". In that account the lottery includes cognitive ability, which complicates any story in which temperament alone does the work. Third, one record is one record. It is not a comparison between people with a 130 and a 160.

For those reasons this page does not estimate his IQ from his wealth, his record or his habits. The same rule governs the other founder pages, on Gates, Jobs and Bezos: a career is evidence about a career. It is not a test result.

12 What should a reader take from this about measuring their own IQ?

A famous cutoff cannot tell you whether your own score is enough, because a quotation about one activity is not a validated interpretation of a score, and professional standards ask for exactly that validation. The Standards for Educational and Psychological Testing, published by AERA, APA and NCME in 2014, ask that each intended interpretation of a score be clearly stated and supported by validity evidence (Standard 1.0). They ask that test users receive clear explanations of what a scale score means and what its limits are (Standard 5.1), and that released results describe in simple language what the test covers, what scores represent and how precise they are (Standard 6.10). The claim that a 125 is enough for investing is not an interpretation that any test states or supports.

The APA Ethics Code bears on the Buffett question directly. Standard 9.01(b) asks psychologists to give opinions about the psychological characteristics of individuals only after an examination adequate to support their conclusions. When that is not practical, they document their efforts, clarify the effect of limited information and limit their conclusions. Standard 9.01(c) covers record reviews and asks them to explain the sources of information their conclusions rest on. A psychologist following that code could say a good deal about what Buffett has said about IQ, as this page does, and nothing about what his IQ is.

The practical advice is to ask of your own result what the standards ask of any other: which test, which norm group, which date, and how much error. ACIS sells a paid assessment, so treat this paragraph as a disclosure. The report gives a Full Scale IQ and six primary indices on the standard scale with a mean of 100 and a standard deviation of 15, with percentiles and a 95 percent confidence interval, and adult norms cover ages 16 to 90. The forms and prices below were read on October 6, 2026 and can change. Quick costs 15 dollars for 6 subtests in 3 domains and takes about 45 minutes, Optimized costs 30 dollars for 13 subtests in 5 domains and takes about 110 minutes, and Full Scale costs 50 dollars for all 20 subtests in six domains and takes about 175 minutes. Payment is one time with no subscription, breaks are allowed, there is a free trial with no card, a 5 day quality guarantee and 30 days to complete.

The limits are plain. ACIS is online and unsupervised, it is not a clinical or diagnostic instrument, it is not for hiring, school accommodations or admission to high IQ societies, and it is available in English only. It measures cognitive abilities and not temperament, risk tolerance or investing skill. The technical manual holds the documentation, and the page on reliability and validity explains how to read it. No ACIS statistic is quoted here. For choosing a test, the comparison of the best online IQ tests and the guide to an IQ test for adults apply the same questions, and the page on what an IQ score means covers interpretation.

13 Sources Behind This Page

Every quotation and figure above is traceable to one of the following, and each is linked at the point where it is used. The rarity table is our own arithmetic on a normal curve with a mean of 100 and a standard deviation of 15, and the counts of IQ mentions come from our own text searches on October 6, 2026 of the sources listed first.

• Buffett WE. Letters to the shareholders of Berkshire Hathaway Inc., 1977 to 2024, posted on the Berkshire Hathaway letters page. The letters for 2007 (signed February 2008) and 2016 (signed February 25, 2017) are the two that contain IQ.
• Abel GE. Letter to the shareholders of Berkshire Hathaway Inc. for 2025, Berkshire Hathaway Inc., February 28, 2026.
• CNBC. Warren Buffett Archive, Berkshire Hathaway annual meeting transcripts, session transcripts for the meetings of 1995, 1996, 1998, 1999, 2000, 2002, 2004, 2005, 2009, 2012, 2015, 2016, 2017, 2018, 2019, 2020 and 2022, read October 6, 2026. Each session is linked in the body.
• BusinessWeek Online. Homespun Wisdom from the "Oracle of Omaha", July 5, 1999 issue, edited by Amey Stone from the notes of Anthony Bianco, Internet Archive copy.
• Lowe J. Warren Buffett Speaks: Wit and Wisdom from the World's Greatest Investor. John Wiley and Sons, 1997. Read as search snippets of the Internet Archive lending copy.
• Buffett W. Lecture at the University of Florida School of Business, October 15, 1998, transcript hosted by Tilson Funds.
• Farnam Street. What makes Warren Buffett a great investor? Intelligence or discipline? Transcript of a 2011 interview in India, with the page on temperament that prints the composite quotation.
• Mejia Z. CNBC Make It article on the IQ score Warren Buffett says is enough to succeed, October 12, 2017. Franck T. Warren Buffett has kept the same investing philosophy for decades, early interview shows. CNBC, September 22, 2019.
• Pages that list a Buffett IQ, read October 6, 2026: Sociosite, History Tools (March 27, 2024) and Boss Hunting (August 22, 2023).
• Grinblatt M, Keloharju M, Linnainmaa J. IQ and Stock Market Participation. The Journal of Finance, 2011, volume 66, issue 6, pages 2121 to 2164.
• Grinblatt M, Keloharju M, Linnainmaa J. Do Smart Investors Outperform Dumb Investors? CRSP Working Paper 09-33, September 10, 2009.
• Chevalier J, Ellison G. Are Some Mutual Fund Managers Better Than Others? Cross-Sectional Patterns in Behavior and Performance. The Journal of Finance, 1999, volume 54, issue 3, pages 875 to 899.
• Stanovich KE, West RF. On the relative independence of thinking biases and cognitive ability. Journal of Personality and Social Psychology, 2008, volume 94, issue 4, pages 672 to 695.
• Sackett PR, Yang H. Correction for range restriction: An expanded typology. Journal of Applied Psychology, 2000, volume 85, issue 1, pages 112 to 118.
• American Educational Research Association, American Psychological Association and National Council on Measurement in Education. Standards for Educational and Psychological Testing. AERA, 2014. Standards 1.0, 5.1 and 6.10 read in the open access PDF.
• American Psychological Association. Ethical Principles of Psychologists and Code of Conduct, text effective January 1, 2017. The apa.org page was not used for reading. Standard 9.01 was read in a public PDF copy of the 2017 text hosted by UT Health San Antonio.

14 Frequently Asked Questions