Statistics of Educational level

Legenda

The educational levels reported by test candidates are encoded as follows:

• 0 = No formal education
• 1 = A few years primary school
• 2 = Primary school completed
• 3 = A few years secondary school
• 4 = Secondary school completed
• 5 = Bachelor
• 6 = Master
• 7 = Doctor

Scores on Educational level as of 26 September 2019

Contents type: Personal information.   

• n: 986
• Mean: 4.84
• σ: 1.20
• Range: 7.0
• Maximum possible: 7
• Male mean: 4.85 (n = 844)
• Female mean: 4.78 (n = 141)
• Resolution: 0.18

Scores by males

n = 844

Scores by females

n = 141

Correlation of Educational level with other tests by Paul Cooijmans

Weighted average of correlations: 0.194 (weighted sum: 643.66)

Conservatively estimated minimum g loading: 0.44

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, including possible floor/ceiling scores or outliers.

Correlation of Educational level with tests by others

Weighted average of correlations: 0.041 (weighted sum: 41.00)

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 5 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.

Correlation of Educational level with other tests by Paul Cooijmans - for females

Weighted average of correlations: 0.453 (weighted sum: 79.31)

Conservatively estimated minimum g loading among females: 0.67

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, including possible floor/ceiling scores or outliers.

Remark: Within females, the correlation of educational level with I.Q. test scores is higher than within males (and females combined).

Estimated loadings of Educational level 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 = 0.34

Note: Although positive, the correlation of educational level with high-range I.Q. test scores (and therewith its g loading) is much too low to allow for a meaningful "norming" or regression of educational levels to I.Q.'s. For high-range test candidates, more education seems to require only marginally more g. This finding is not entirely inconsistent with what one may informally observe when communicating with persons who use academic titles in the high-I.Q. community.

National means for Educational level

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 Educational level

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

• r = -0.03 (n = 979)

Correlation of Educational level with personal details

Correlation with personal details of Educational level - within females

Remarkable is that "Observed behaviour" is the lowest correlate of educational level in females, but the highest in males. GAIA (Gifted Adult's Inventory of Aspergerisms) is among the lowest for both sexes.

Correlation with personal details of Educational level - within males

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.

Conclusions

1. There is, on the whole, a very small positive correlation of educational level with high-range I.Q. test scores (it is in fact .04 to .19);
2. Within females, however, there is a low positive correlation of about .45;
3. Only downward of educational level 3 (a few years secondary school) there seems to be a somewhat higher correlation with I.Q.;
4. Scores on the Gifted Adult's Inventory of Aspergerisms correlate negatively with educational level.

Disclaimer

Mistaken responses to a previous version of this report have made the following disclaimer necessary: This report deals only with statistics of high-range test candidates. Within the general population, there is no doubt a much higher correlation of educational level with I.Q. than reported for the high-range population. This difference has to do with phenomena like attenuation due to restriction of range, and Spearman's "law of diminishing returns" regarding g. Incorrect reporting by candidates may also play a role; some seem to report higher educational levels than they have, and notorious is the unauthorized used of the doctor title in high-I.Q. circles.