Statistics of Isis Test

© August 2017 Paul Cooijmans


Scores on Isis Test

Contents type: Verbal, numerical.   Period: 2001-present

0 *************************************************
1 **********
2 *

Note: Means instead of medians are used in this report because of the very limited variance in scores, which makes medians less informative.

Correlation of Isis Test with other tests by Paul Cooijmans

(Test index) Test name n r
(47) Psychometrically Activated Grids Acerbate Neuroticism31.00
(46) Labyrinthine LIMIT40.97
(12) Cooijmans On-Line Test - Two-barrelled version90.82
(56) Short Test For Genius40.81
(48) Narcissus' last stand100.74
(36) Reflections In Peroxide110.73
(18) The Nemesis Test180.72
(68) Numbers110.66
(21) Psychometric Qrosswords40.65
(0) Test of the Beheaded Man80.64
(82) Reason70.62
(35) Intelligence Quantifier by assessment190.61
(69) Odds60.60
(103) Problems In Gentle Slopes of the second degree70.59
(4) A Paranoiac's Torture: Intelligence Test Utilizing Diabolic Exactitude100.58
(66) Test For Genius - Revision 2004160.55
(42) The Marathon Test60.55
(62) Reason Behind Multiple-Choice70.53
(31) Numerical section of The Marathon Test70.52
(85) Cooijmans Intelligence Test - Form 130.50
(43) Test For Genius - Revision 201080.49
(5) Daedalus Test80.47
(45) Numerical and spatial sections of The Marathon Test70.44
(15) Letters70.44
(30) Verbal section of The Marathon Test60.41
(27) Spatial section of Test For Genius - Revision 2004210.40
(3) Qoymans Multiple-Choice #5200.39
(10) Genius Association Test140.39
(19) Numerical section of Test For Genius - Revision 2010140.39
(26) Verbal section of Test For Genius - Revision 2004210.38
(1) Cartoons of Shock120.37
(41) The LAW - Letters And Words60.35
(33) Problems In Gentle Slopes of the first degree50.35
(28) The Test To End All Tests160.35
(39) Combined Numerical and Spatial sections of Test For Genius - Revision 201090.35
(23) Gliaweb Riddled Intelligence Test - Revision 201160.34
(84) Bonsai Test80.34
(104) The Final Test - Revision 201360.33
(32) Spatial section of The Marathon Test70.32
(25) The Sargasso Test120.32
(2) Cooijmans Intelligence Test - Form 3110.30
(29) Words60.29
(57) Space, Time, and Hyperspace100.28
(40) Reason Behind Multiple-Choice - Revision 2008200.26
(55) Spatial Insight Test40.26
(44) Associative LIMIT100.26
(87) Cooijmans Intelligence Test - Form 290.25
(63) Long Test For Genius90.21
(7) The Final Test120.21
(75) Analogies of Long Test For Genius90.14
(16) Lieshout International Mesospheric Intelligence Test130.12
(24) Reason - Revision 2008200.07
(80) Qoymans Multiple-Choice #4150.06
(79) Association subtest of Long Test For Genius9-0.17

Weighted average of correlations: 0.406

Conservatively estimated minimum g loading: 0.64

Ranking in above table is based on the unrounded correlations. All available data is present in this table, no tests are left out except for those with less than 3 score pairs. All known pairs are used, including possible floor/ceiling scores or outliers.

Correlation of Isis Test with tests by others

(Test index) Test name n r
(211) Culture Fair Numerical Spatial Examination - Final version30.78
(248) Gliaweb Riddled Intelligence Test (old version)40.64
(239) Titan Test90.46
(242) Unknown and miscellaneous tests180.43
(225) Logima Strictica 3670.09
(234) Strict Logic Sequences Exam I8-0.04
(243) Scholastic Aptitude Test (old)4-0.10
(240) Strict Logic Spatial Exam 485-0.43
(241) Ultra Test3-0.90

Weighted average of correlations: 0.195

Ranking in above table is based on the unrounded correlations. All available data is present in this table, no tests are left out except for those with less than 3 score pairs. All known pairs are used, including possible floor/ceiling scores or outliers.

Please be aware that correlations with these external tests are in most cases affected (depressed, typically) by one or more of the following: (1) Little overlap with the object test because of the much lower ceilings and inherent ceiling effects of the tests used in regular psychology; (2) Candidates reporting scores selectively, for instance only the higher ones while withholding lower ones; (3) Candidates reporting, or having been reported by psychometricians, incorrect scores.

Estimated loadings of Isis Test on particular item types

These are estimated g factor loadings, but against homogeneous tests (containing only particular item types) as opposed to non-compound heterogeneous tests. Although tending to surprise the lay person, it is not uncommon for tests to have high loadings on item types they do not actually contain themselves. Such loadings reflect the empirical fact that most tests for mental abilities measure primarily g, regardless of their contents; that the major part of test score variance is caused by g, and only a minor part by factors germane to particular item types. It is of key importance to understand that this is a fact of nature, a natural phenomenon, and not something that was built into the tests by the test constructors.

Typeg loading of Isis Test on that type

Compound tests have been left out of this table to avoid overlap.

Balanced g loading = 0.61

National means for Isis Test

Country n mean score

For reasons of privacy, only countries with 2 or more candidates are included in this table. Ranking is based on the unrounded means, and then alphabetic.

Correlation with national I.Q.'s of Isis Test

Correlation of this test with national average I.Q.'s published by Lynn and Vanhanen:

Correlation of Isis Test with personal details

Personalia n r
P.S.I.A. System factor100.87
Observed associative horizon90.79
P.S.I.A. Cold160.77
P.S.I.A. Rational160.70
P.S.I.A. Just160.70
Observed behaviour160.49
P.S.I.A. True160.45
P.S.I.A. Ethics factor200.44
P.S.I.A. Aspergoid160.33
P.S.I.A. Introverted160.31
P.S.I.A. Deviance factor200.27
Year of birth590.22
P.S.I.A. Rare160.22
Mother's educational level460.17
Candidate's self-estimated I.Q.90.16
P.S.I.A. Neurotic160.07
P.S.I.A. Antisocial160.01
Gifted Adult's Inventory of Aspergerisms13-0.01
P.S.I.A. Cruel16-0.02
Father's educational level45-0.03
P.S.I.A. Extreme16-0.08
Educational level49-0.08
P.S.I.A. Orderly16-0.14
Disorders (parents and siblings)48-0.23
Disorders (own)48-0.25
Cooijmans Inventory of Neo-Marxist Attitudes4-0.85

Reliability and error

Due to the very small number of items and very limited variance in scores and item scores, it is not possible to compute reliability and error meaningfully for this test from its internal statistics. What can be said is that a test's reliability is necessarily higher than its g loading because reliability puts an upper limit on a test's possible correlations with any other variables.

Scores by age

Age class n mean score
70 to 7410.00
55 to 5920.00
50 to 5460.00
45 to 4940.25
40 to 4440.50
35 to 3960.00
30 to 3440.25
25 to 29150.07
22 to 2460.50
20 or 2120.00
18 or 1970.29

Scores by year taken

Year taken n mean score

ryear taken × mean score = 0.35 (n = 61)

Robustness and overall test quality

Item analysis

Item statistics are not published as that would help future candidates. To detect bad items, answers and comments from candidates are studied, as well as, for each problem, the correlation with total score and the proportion of candidates getting it wrong (hardness of the item). Possible bad items are removed or revised, resulting in a revised version of the test.