Statistics of Gliaweb Riddled Intelligence Test

Note

This test has been succeeded by the Gliaweb Riddled Intelligence Test — Revision 2011.

Scores on Gliaweb Riddled Intelligence Test (old version) as of 11 September 2024

Contents type: Verbal, numerical, spatial, logical.   Period: 2007-2011

• n: 45
• Median: 35.0
• Quartile deviation: 2.0
• Range: 16
• Maximum possible: 42
• Male median: 35.0 (n = 41)
• Female median: 33.5 (n = 4)
• Proportion of males among candidates: 0.911
• Hardness: 0.17
• Resolution: 0.29

Correlation of Gliaweb Riddled Intelligence Test (old version) with other mental ability tests

Weighted average of correlations: 0.184 (N = 153)

Estimated g factor loading: 0.43

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 4 score pairs. All known pairs are used, including possible floor/ceiling scores or outliers.

Remark: The very low g loading is caused by (1) the narrow range of scores and low number of effective items resulting from the easy nature of the test, (2) a few bad items, and (3) possible fraud by a small number of candidates (one likely fraudulent score has been excluded here).

Estimated loadings of Gliaweb Riddled Intelligence Test (old version) 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.

N = 92

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

Balanced g loading = 0.40

National medians for Gliaweb Riddled Intelligence Test (old version)

For reasons of privacy, only countries with 3 or more candidates are included in this table. Ranking is based on the medians, and then alphabetic.

Correlation with national I.Q.'s of Gliaweb Riddled Intelligence Test (old version)

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

• r = -0.01 (n = 44)

Correlation of Gliaweb Riddled Intelligence Test (old version) with personal details

Estimated g factor loadings for restricted ranges

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 these values to be lower than the test's full-range g loading.

Reliability

• Split-half (odd-even) = 0.54
• Split-half (1, 2… 5, 6… vs. 3, 4… 7, 8…) = 0.63
• Cronbach's alpha = 0.68

Remark: This low reliability (and therefore large error of measurement) is mainly caused by the fact that many of the test's items were never or rarely missed, so that the test effectively had fewer items that it seemed (a shorter test has lower reliability). This can also be understood when looking at the narrow range of scores. There were also some bad items, which have been revised before inclusion in the Revision 2011 of the test.

Reliability puts an upper limit on the test's possible (true, significant) correlations with other tests, and thus this low reliability also causes the test's g loading to be low.

Error

• Standard error = 1.9 raw score points

Scores by age

N = 44

Scores by year taken

r_{year taken × median score} = 0.38 (N = 44)

Robustness and overall test quality

• Robustness by month = 0.62 (r_{raw scores × months} = 0.24)
• Quality = 0.468

Item analysis

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

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