Editing Intelligence quotient (section)

==Current tests==
[[File:IQ distribution.svg|class=skin-invert-image|thumb|upright=1.2|Normalized IQ distribution with mean 100 and standard deviation 15]]
There are a variety of individually administered IQ tests in use in the English-speaking world.<ref name="Urbina2011Table2.1" /><ref name="FlanaganHarrison2012chs8-16" /><ref>{{Citation |last1=Stanek |first1=Kevin C. |title=Taxonomies and Compendia of Cognitive Ability and Personality Constructs and Measures Relevant to Industrial, Work and Organizational Psychology |date=2018 |url=http://sk.sagepub.com/reference/the-sage-handbook-of-industrial-work-and-org-psychology-vol1/i3345.xml |work=The SAGE Handbook of Industrial, Work and Organizational Psychology: Personnel Psychology and Employee Performance |pages=366–407 |access-date=2024-01-08 |place=1 Oliver's Yard, 55 City Road London EC1Y 1SP |publisher=SAGE Publications Ltd |doi=10.4135/9781473914940.n14 |isbn=978-1-4462-0721-5 |last2=Ones |first2=Deniz S.}}</ref> The most commonly used individual IQ test series is the [[Wechsler Adult Intelligence Scale]] (WAIS) for adults and the [[Wechsler Intelligence Scale for Children]] (WISC) for school-age test-takers. Other commonly used individual IQ tests (some of which do not label their standard scores as "IQ" scores) include the current versions of the [[Stanford–Binet Intelligence Scales]], [[Woodcock–Johnson Tests of Cognitive Abilities]], the [[Kaufman Assessment Battery for Children]], the [[Cognitive Assessment System]], and the [[Differential Ability Scales]].

There are various other IQ tests, including:
# [[Raven's Progressive Matrices]] (RPM)
# [[Cattell Culture Fair III]] (CFIT)
# [[Reynolds Intellectual Assessment Scales]] (RIAS)
# [[Primary Mental Abilities Test|Thurstone's Primary Mental Abilities]]<ref>{{Cite web|title = Primary Mental Abilities Test {{!}} psychological test|url = https://www.britannica.com/topic/Primary-Mental-Abilities-Test|website = Encyclopædia Britannica|access-date = 26 November 2015}}</ref><ref>{{Cite web|title = Defining and Measuring Psychological Attributes|url = http://homepages.rpi.edu/~verwyc/TESTOH2.htm|website = homepages.rpi.edu|access-date = 26 November 2015|archive-date = 15 October 2018 |archive-url = https://web.archive.org/web/20181015132922/http://homepages.rpi.edu/~verwyc/TESTOH2.htm|url-status = dead}}</ref>
# [[Kaufman Brief Intelligence Test]] (KBIT)<ref>{{Cite journal|title = Test Review: Review of Kaufman Brief Intelligence Test, Second Edition Kaufman, A. S., & Kaufman, N. L. (2004). Kaufman Brief Intelligence Test, Second Edition. Bloomington, MN: Pearson, Inc|journal = Journal of Psychoeducational Assessment|date = 1 April 2010|issn = 0734-2829|pages = 167–174|volume = 28|issue = 2|doi = 10.1177/0734282909348217|first1 = Sherry K.|last1 = Bain|first2 = Kathryn E.|last2 = Jaspers|s2cid = 143961429}}</ref>
# [[Multidimensional Aptitude Battery II]]
# [[Das–Naglieri cognitive assessment system]] (CAS)
# [[Naglieri Nonverbal Ability Test]] (NNAT)
#[[Wide Range Intelligence Test]] (WRIT)

IQ scales are [[Ordinal scale|ordinally scaled]].<ref>{{cite book|title=Psychology: An Introduction |last=Mussen |first=Paul Henry |year=1973 |publisher=Heath |location=Lexington, MA |isbn=978-0-669-61382-7 |page=[https://archive.org/details/psychologyintrod00muss/page/363 363] |quote=The I.Q. is essentially a rank; there are no true "units" of intellectual ability. |url=https://archive.org/details/psychologyintrod00muss/page/363}}</ref><ref>{{cite book |title=The WISC-III Companion: A Guide to Interpretation and Educational Intervention |last=Truch |first=Steve |year=1993 |publisher=Pro-Ed |location=Austin, TX |isbn=978-0-89079-585-9 |page=35 |quote=An IQ score is not an equal-interval score, as is evident in Table A.4 in the WISC-III manual.}}</ref><ref>{{cite book |title=Measuring Intelligence: Facts and Fallacies |url=https://archive.org/details/measuringintelli00bart |url-access=limited |last=Bartholomew |first=David J. |author-link=D.J. Bartholomew |year=2004 |publisher=Cambridge University Press |location=Cambridge |isbn=978-0-521-54478-8 |quote=When we come to quantities like IQ or g, as we are presently able to measure them, we shall see later that we have an even lower level of measurement—an ordinal level. This means that the numbers we assign to individuals can only be used to rank them—the number tells us where the individual comes in the rank order and nothing else. |page=[https://archive.org/details/measuringintelli00bart/page/n65 50]}}</ref><ref>{{harvnb|Mackintosh|1998|pp=[https://archive.org/details/iqhumanintellige00mack/page/30 30–31]}} "In the jargon of psychological measurement theory, IQ is an ordinal scale, where we are simply rank-ordering people. ... It is not even appropriate to claim that the 10-point difference between IQ scores of 110 and 100 is the same as the 10-point difference between IQs of 160 and 150"</ref><ref>{{cite journal |last=Stevens |first=S. S. |author-link=Stanley Smith Stevens |title=On the Theory of Scales of Measurement |journal=[[Science (journal)|Science]] |volume=103 |issue=2684 |pages=677–680 |year=1946 |pmid=17750512 |doi=10.1126/science.103.2684.677 |bibcode=1946Sci...103..677S |s2cid=4667599}}</ref> The [[Test score|raw score]] of the norming [[Sample (statistics)|sample]] is usually (rank order) [[Data transformation (statistics)|transformed]] to a [[normal distribution]] with mean 100 and [[standard deviation]] 15.<ref name="Gottfredson2009pp31–32" /> While one [[standard deviation]] is 15 points, and two SDs are 30 points, and so on, this does not imply that mental ability is linearly related to IQ, such that IQ 50 would mean half the cognitive ability of IQ 100. In particular, IQ points are not percentage points.