Statistics of Numerical and Spatial sections of Test For Genius - Revision 2010

Scores on Combined Numerical and Spatial sections of Test For Genius - Revision 2010 as of 13 September 2019

Contents type: Numerical, spatial.   Period: 2010-2016

• n: 58
• Median: 15.8
• Quartile deviation: 3.0
• Range: 25
• Maximum possible: 39
• Male median: 16.0 (n = 55)
• Female median: 13.5 (n = 1)
• Resolution: 0.35

Note: The statistics of this test suffer somewhat from a lack of very high scores.

Correlation of Combined Numerical and Spatial sections of Test For Genius - Revision 2010 with other tests by Paul Cooijmans

Weighted average of correlations: 0.628 (weighted sum: 426.63)

Conservatively estimated minimum g loading: 0.79

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 Combined Numerical and Spatial sections of Test For Genius - Revision 2010 with tests by others

Weighted average of correlations: 0.333 (weighted sum: 22.63)

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 Combined Numerical and Spatial sections of Test For Genius - Revision 2010 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.

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

Balanced g loading = 0.75

National medians for Combined Numerical and Spatial sections of Test For Genius - Revision 2010

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 national I.Q.'s of Combined Numerical and Spatial sections of Test For Genius - Revision 2010

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

• r = -0.15 (n = 56)

Correlation of Combined Numerical and Spatial sections of Test For Genius - Revision 2010 with personal details

Estimated g factor loadings upward and downward of particular scores

In parentheses the number of score pairs on which that estimated g factor loading is based. The goal of this is to verify the hypothesis that g becomes less important, accounts for a smaller proportion of the variance, at higher I.Q. levels. The mere fact of restricting the range like this also depresses the g loading compared to computing it over the test's full range, so it would be normal for both values to be lower than the test's full-range g loading.

Note: From 18 upward this looks not so good. The Revision 2016 of the test aims to improve on this. The cause of this problem may lie partly or wholly in certain peculiarities of this group of candidates (rather than in the test itself) and that aspect is tackled in the Revision 2016 as well.

Reliability

The reliability of this test has been computed from the two subtest reliabilities using a form of the Spearman-Brown formula as .84. This is on the low side for a subtest that is also used as a test on its own. Again, the Revision 2016 should do better (see above paragraph).

Error

• Standard error = 2.1 raw score points

Robustness and overall test quality

• Robustness by month = 0.67 (r_{raw scores × months} = 0.10)
• Quality = 0.728

Further internal statistics

Further internal statistics are reported on subtest level; it concerns the subtests Numerical section of Test For Genius - Revision 2010 and Spatial section of Test For Genius - Revision 2004, each having their own statistical report.