Statistics of Cooijmans Intelligence Test - Form 2

Norms

Scores

# candidates: 61
Median: 22.5
Quartile deviation: 3.5
Range: 36.5
Maximum possible: 39
Mean: 21.9
Standard deviation: 7.08
Male median: 22.5
Female median: 20.0 (# females: 4)
Hardness: 0.42
Resolution: 0.44

0	**
7.5	*
10	*
11	*
13	*
14	*
15	*
16	*
17	***
18	**
18.5	**
19	*
20	******
20.5	***
21	*
22	***
22.5	***
23	**
23.5	**
24	****
24.5	*
25	***
25.5	*
26	*
27	*
28	***
29	*
29.5	**
30	*
31	*
31.5	*
32.5	*
33	*
34.5	*
36.5	*

Correlation with other tests

Test	#	cor
The Nemesis Test	6	0.98
The Marathon Test	6	0.92
Culture Fair Numerical Spatial Examination - C	5	0.91
Test For Genius - Revision 2004	19	0.89
Mysterium Entrance Exam	6	0.87
Long Test For Genius	5	0.87
Qoymans Multiple-Choice #5	7	0.85
The Sargasso Test	7	0.83
Spatial section of Test For Genius - Revision 2004	19	0.82
Reason Behind Multiple-Choice - Revision 2008	7	0.80
Verbal section of Test For Genius - Revision 2004	19	0.80
Association subtest of Long Test For Genius	6	0.78
Analogies of Long Test For Genius	5	0.77
Odds	5	0.75
Culture Fair Numerical Spatial Examination - Final version	14	0.74
Verbal section of The Marathon Test	6	0.67
Strict Logic Spatial Exam 48	7	0.66
Logima Strictica 36	13	0.65
Numbers	9	0.65
Nonverbal Cognitive Performance Examination	9	0.64
Spatial Insight Test	9	0.63
The Test To End All Tests	10	0.60
Titan Test	5	0.60
Genius Association Test	17	0.58
Reason Behind Multiple-Choice	14	0.58
The Final Test	11	0.58
Numerical section of The Marathon Test	6	0.56
Associative LIMIT Test	15	0.56
Reason - Revision 2008	7	0.56
Space, Time and Hyperspace	13	0.53
Reason	14	0.52
Qoymans Multiple-Choice #4	19	0.51
International High IQ Society Miscellaneous tests	6	0.50
Lieshout International Mesospheric Intelligence Test	21	0.48
Test of Shock and Awe	7	0.41
Strict Logic Sequences Exam I	15	0.41
Spatial section of The Marathon Test	6	0.35
Cartoons of Shock	9	0.34
Unknown tests	7	-0.02
Bonsai Test	6	-0.28
Strict Logic Sequences Exam II	5	-0.58

Weighted average of correlations: 0.604

Conservatively estimated minimum g loading: 0.78

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 5 score pairs. All known pairs are used to obtain the true, honest statistics; Correlations are not artificially inflated by leaving out ceiling scores, outliers or other anomalies.

National medians

Country	# scores	Median score
Spain	2	26.8
Canada	3	25.5
Sweden	3	25.0
Germany	2	24.0
Turkey	3	24.0
United_Kingdom	4	23.0
Belgium	3	22.0
Poland	2	21.8
Netherlands	7	20.0
United_States	11	20.0
Finland	8	18.5
Norway	2	16.5

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

Correlation with personal details

Personalia	#	cor
Observed associative horizon is wide	3	0.76
Cattell Culture Fair	9	0.47
P.S.I.A. System factor (phased out)	7	0.46
P.S.I.A. Rare	27	0.43
P.S.I.A. Aspergoid	27	0.38
Wechsler Adult Intelligence Scales	6	0.33
W-87	4	0.33
P.S.I.A. Neurotic	27	0.33
Gifted Adult's Inventory of Aspergerisms	11	0.29
P.S.I.A. Cold	27	0.29
P.S.I.A. Antisocial	27	0.28
P.S.I.A. Cruel	27	0.27
Mother's educational level	58	0.26
Raven's Advanced Progressive Matrices (I.Q.)	5	0.26
P.S.I.A. Deviance factor	30	0.24
Father's educational level	58	0.23
Is male	61	0.22
P.S.I.A. Introverted	27	0.18
P.S.I.A. True	27	0.15
Observed behaviour is good	8	0.14
Year of birth	61	0.12
Educational level	58	0.06
Number of characters in candidate's name as registered	61	0.02
Is resident of the European Union	31	0.01
P.S.I.A. Ethics factor	30	-0.04
P.S.I.A. Rational	27	-0.05
P.S.I.A. Just	27	-0.05
P.S.I.A. Orderly	27	-0.19
P.S.I.A. Extreme	27	-0.20
Disorders (own)	58	-0.24
Disorders (parents and siblings)	58	-0.26
Raven's Advanced Progressive Matrices (raw)	3	-0.58

Correlation with personal details - within females

Personalia	#	cor
Father's educational level	3	1.00
Mother's educational level	3	1.00
Educational level	3	0.99
Disorders (own)	3	0.63
Number of characters in candidate's name as registered	4	0.49
Disorders (parents and siblings)	3	-0.36
Year of birth	4	-0.91

Correlation with national I.Q.s

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

r = -0.09 (n = 61)

Estimated g factor loadings Upward and Downward of specific scores

In parentheses the number of score pairs on which that estimated g factor loading is based. The Upward and Downward values are calculated including the pertinent score itself. It is normal that g factor loadings go down when the range is restricted like this, but careful study of the Upward and Downward columns may reveal possible scores below or above which the test loses validity altogether.

Score	Upward (n)	Downward (n)
0	.76 (499)	NaN (0)
5	.73 (468)	NaN (0)
10	.7 (450)	-.15 (19)
15	.59 (406)	.63 (60)
20	.6 (337)	.74 (172)
22.5	.6 (266)	.73 (206)
25	.63 (177)	.71 (325)
27.5	.72 (84)	.73 (378)
30	.72 (30)	.72 (447)
32	.78 (21)	.73 (453)
33	.76 (19)	.73 (473)
34	1.00 (2)	.73 (473)
36.5	NaN (0)	.76 (499)

Reliability

Split-half = 0.91
Cronbach's alpha = 0.91

Error

Standard error = 2.1 raw score points
Quartile error = 1.0 raw score points
Range of error = 10.8 raw score points

Scores by age

Age group	# scores	Median score
60 to 64	1	7.5
50 to 54	3	20.5
45 to 49	5	22.0
40 to 44	5	25.0
35 to 39	9	20.0
30 to 34	11	20.5
25 to 29	13	23.0
22 to 24	7	25.5
20 or 21	3	22.0
18 or 19	3	22.5
17	1	20.5

Scores by age - within females

Age group	# scores	Median score
35 to 39	2	22.0
30 to 34	2	9.9

Scores by year taken

Year taken	# candidates	Median score
2004	7	23.5
2005	14	22.3
2006	9	25.0
2007	11	20.0
2008	14	22.8
2009	6	25.0

Correlation year taken versus median score = 0.11
n = 61

Robustness and overall test quality

Robustness = 1.00
Quality = 0.80

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 (validity of the item in this test) 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.

Correlations of sections with total score

Verbal	0.91
Numerical	0.91
Spatial	0.88

Correlations between sections

Verbal × Numerical	0.74
Verbal × Spatial	0.70
Numerical × Spatial	0.71

Section histograms

Prop. = proportion of candidates outscored in this section.

Verbal

Raw	Prop.	Scores (* = 1 candidate)
0	0.015	**
4	0.045	**
5	0.083	***
6.75	0.114	*
7	0.129	*
7.5	0.159	***
8	0.205	***
8.5	0.250	***
9	0.303	****
9.25	0.341	*
9.5	0.364	**
9.75	0.386	*
10	0.462	*********
10.5	0.621	************
10.75	0.720	*
11	0.773	******
11.5	0.856	*****
12	0.909	**
12.5	0.932	*
13.5	0.955	**
14	0.977	*
14.5	0.992	*

Numerical

Raw	Prop.	Scores (* = 1 candidate)
0	0.015	**
2	0.045	**
2.5	0.068	*
3.5	0.083	*
4	0.106	**
4.25	0.129	*
5	0.152	**
5.25	0.174	*
5.5	0.212	****
5.75	0.250	*
6	0.280	***
6.5	0.311	*
7	0.341	***
7.5	0.417	*******
8	0.530	********
8.25	0.598	*
8.5	0.621	**
9	0.652	**
9.5	0.720	*******
9.75	0.780	*
10	0.818	****
10.5	0.871	***
11	0.917	***
11.5	0.947	*
11.75	0.962	*
12	0.985	**

Spatial

Raw	Prop.	Scores (* = 1 candidate)
0	0.023	***
1	0.061	**
1.25	0.083	*
1.5	0.098	*
2	0.121	**
2.5	0.152	**
3	0.205	*****
3.5	0.280	*****
4	0.364	******
4.5	0.485	**********
5	0.606	******
5.5	0.667	**
6	0.727	******
6.25	0.780	*
6.5	0.795	*
7	0.818	**
7.5	0.841	*
8	0.864	**
8.5	0.902	***
9	0.939	**
9.5	0.970	**
10.5	0.992	*