Qoymans Multiple-Choice #3 Statistics

Norms

Correlation with other tests

Weighted average of correlations: 0.364

Conservatively estimated minimum g loading: 0.6

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.

Additional statistics November 2014

Scores on Qoymans Multiple-Choice #3

Contents type: Verbal.   Period: 2002-2004

• n: 282
• Median: 38.0
• Quartile deviation: 13.5
• Range: 200
• Maximum possible: 100
• Minimum possible: -100
• Male median: 43.0 (n = 212)
• Female median: 27.0 (n = 61)
• Hardness: 0.31
• Resolution: 0.75

Scores by males

n = 212

Scores by females

n = 61

Correlation of Qoymans Multiple-Choice #3 with other tests by Paul Cooijmans

Weighted average of correlations: 0.436

Conservatively estimated minimum g loading: 0.66

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 have not been artificially inflated by leaving out ceiling scores, outliers or other anomalies.

Correlation of Qoymans Multiple-Choice #3 with tests by others

Weighted average of correlations: 0.203

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 have not been artificially inflated by leaving out ceiling scores, outliers or other anomalies.

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.

Correlation of Qoymans Multiple-Choice #3 with other tests by Paul Cooijmans - for females

Weighted average of correlations: 1.000

Conservatively estimated minimum g loading among females: 1.00

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

Estimated loadings of Qoymans Multiple-Choice #3 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 = 0.52

Correlation of Qoymans Multiple-Choice #3 with personal details

Correlation with personal details of Qoymans Multiple-Choice #3 - within females

Correlation with personal details of Qoymans Multiple-Choice #3 - within males

Correlation with national I.Q.'s of Qoymans Multiple-Choice #3

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

• r = 0.05 (n = 107)

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.

Reliability - Earlier period

In the early period the test was free and no registration was required.

• Split-half (odd-even) = 0.88
• Split-half (other division) = 0.89
• Cronbach's alpha = 0.87

Reliability - Later period

In the later period registration was required before being able to take the test, and eventually there was a fee. These measures have improved the functioning of the test; for instance, people do their best more, retests under false names become much rarer, the average I.Q. of the candidates is much higher, reliability is higher, and so on.

• Split-half (odd-even) = 0.95
• Split-half (other division) = 0.94
• Cronbach's alpha = 0.94

Error - Earlier period

• Standard error = 6.0 raw score points

Error - Later period

• Standard error = 5.7 raw score points

Scores by age - Earlier period

Scores by age - Later period

Scores by age - within females - Earlier period

Scores by age - within females - Later period

Scores by age - within males - Earlier period

Scores by age - within males - Later period

Scores by year taken - Earlier period

r_{year taken × median score} = -1.00 (n = 143)

Scores by year taken - Later period

r_{year taken × median score} = -0.54 (n = 140)

Robustness and overall test quality - Earlier period

• Robustness by chronological rank = 0.67
• Robustness by month = 0.71

Robustness and overall test quality - Later period

• Robustness by chronological rank = 0.71
• Robustness by month = 0.73
• Quality = 0.67

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.