View source for Stanine

{{Short description|Method of scaling test scores}}
{{Distinguish|Stanene}}

'''Stanine''' (STAndard NINE) is a method of scaling test scores on a nine-point standard scale with a [[mean]] of five and a [[standard deviation]] of two.

Some web sources attribute stanines to the [[United States Army Air Forces|U.S. Army Air Forces]] during [[World War II]]. Psychometric legend has it that a 1–9 scale was used because of the compactness of recording the score as a single digit but Thorndike<ref>Thorndike, R. L.  (1982).  Applied Psychometrics. Boston, MA: Houghton Mifflin</ref>  claims that by reducing scores to just nine values, stanines "reduce the tendency to try to interpret small score differences (p. 131)". The earliest known use of stanines was by the U.S. Army Air Forces in 1942.<ref>Krueger Hussey, A. (2004).  Air Force Flight Screening: Evolutionary Changes, 1917-2003. Office of History and Research Headquarters Air Education and Training Command Randolph AFB, Texas</ref>

==Calculation==
Test scores are scaled to stanine scores using the following algorithm:
# Rank results from lowest to highest
# Give the lowest 4% a stanine of 1, the next 7% a stanine of 2, etc., according to the following table:

{| class="wikitable" style="text-align:center"
|+ Calculating Stanines
|- bgcolor="#eeeeee" 
| '''Bracketed<br/>proportion'''|| width="9%" |4%|| width="9%" |7%|| width="9%" |12%|| width="9%" |17%|| width="9%" |20%|| width="9%" |17%|| width="9%" |12%|| width="9%" |7%|| width="9%" |4%
|- bgcolor="#dddddd" 
| '''Stanine''' || 1 || 2 || 3 || 4 || 5 || 6 || 7 || 8 || 9
|- bgcolor="#dddddd"
| '''Standardized<br/>score''' || below −1.75 || −1.75 to −1.25 || −1.25 to −0.75 || −0.75 to −0.25 || −0.25 to +0.25 || +0.25 to +0.75 || +0.75 to +1.25 || +1.25 to +1.75 || above +1.75
|- bgcolor="#dddddd"
| '''Wechsler<br/>scale score''' || below 74 || 74 to 81 || 81 to 89 || 89 to 96 ||96 to 104 || 104 to 111 || 111 to 119 || 119 to 126 || above 126
|- bgcolor="#eeeeee"
| '''Cumulative proportion''' || 4% || 11% || 23% || 40% || 60% || 77% || 89% || 96% || 100%
|}

The underlying basis for obtaining stanines is that a [[normal distribution]] is divided into nine intervals, each of which has a width of 0.5 standard deviations excluding the first and last, which are just the remainder (the tails of the distribution). The [[median]] lies at the centre of the fifth interval.

==Use today==
Today stanines are mostly used in educational assessment.{{Citation needed|date=November 2010}} 
* The [[University of Alberta]] in [[Edmonton, Alberta]], Canada used the stanine system until 2003, when it switched to a 4-point scale.<ref>{{cite web |url=http://www.registrar.ualberta.ca/ro.cfm?id=184 |title=Grade Comparison Guide |access-date=2007-01-04 |url-status=dead |archive-url=https://web.archive.org/web/20061212012831/http://www.registrar.ualberta.ca/ro.cfm?id=184 |archive-date=2006-12-12 }}</ref>  
* In the United States, the [[Educational Records Bureau]] (they administer the "ERBs") reports test scores as stanines and percentiles.
* In Europe, [[EUROCONTROL]] scores its FEAST Test - a test used for selecting candidates for ATC - using stanines. 
* The [[NZCER|New Zealand Council for Educational Research]] uses stanines.<ref>[http://www.nzcersupport.org.nz/marking/?p=75 "Understanding Stanines"], nzcersupport.org.nz</ref>
* GL Assessment use stanines alongside SAS (Standardised Age Scores) to express the results of its CAT4 assessments, used in many UK and British international schools <ref>[http://www.gl-assessment.co.uk/products/cat4-cognitive-abilities-test-fourth-edition "GL Assessment"]</ref>
* The [[Otis-Lennon School Ability Test]] uses a stanine system along with percentiles.
* High schools in Korea use a stanine system to evaluate their students.
* The IDF (Israeli Defense Force) uses the stanine grading system ranging from 10 to 90 (10, 20, 30 and so on) to rank intelligence ability relevant to the army's use, determined by a 100 question test divided to 4 categories having to do with different uses and implications of cognitive abilities
* The Polish [[Matura]] secondary-school exam results and university admissions utilise the stanine system

==See also==
* [[Sten scores]] – a similar system, but with 10 possible values
* [[Normal score]]

==Notes==
{{Reflist}}

==References==
* {{cite web
 |last=Ballew |first=Pat
 |date=c. 2002
 |title=Origins of some arithmetic terms |page=3
 |department=Math words
 |website=pballew.net
 |url=http://www.pballew.net/arithme3.html#stanine
 |access-date=26 December 2004
 |url-status=usurped |archive-url=https://web.archive.org/web/20160605170324/http://www.pballew.net/arithme3.html#stanine
 |archive-date=2016-06-05
}} 
* {{cite web
 |last=Boydsten |first=Robert E.
 |date=27 February 2000
 |title=Winning My Wings
 |website=boydstonfoundation.org
 |url=http://www.boydstonfoundation.org/WINGS32.html
 |url-status=dead <!-- presumed -->
 |archive-url=https://web.archive.org/web/20080514031604/http://www.boydstonfoundation.org/WINGS32.html
 |archive-date=2008-05-14
}} 

* {{cite book
 |editor1-first=Wesley Frank |editor1-last=Craven
 |editor2-first=James Lea    |editor2-last=Cate
 |orig-year=1955  |year=1983
 |title=Men and Planes |volume=6 |edition=new imprint
 |series=The Army Air Forces in World War&nbsp;II
 |publisher=University of Chicago Press (1955) / Office of Air Force History (1983) |place=Chicago, IL
 |lccn=48-3657  |ISBN=0-912799-03-X  |id=AFD-101105-019
 |via=afhso.af.mil
 |url=http://www.afhso.af.mil/shared/media/document/AFD-101105-019.pdf 
 |archive-url=https://web.archive.org/web/20161123154009/http://www.afhso.af.mil/shared/media/document/AFD-101105-019.pdf
 |archive-date=2016-11-23
}}

[[Category:Educational assessment and evaluation]]
[[Category:Scales]]
[[Category:Comparison of assessments]]
[[Category:Psychometrics]]