Thurstone-Brown agreement was closer than Otis-Illinois: median rank changes of 6.7 places (freshmen, r = 0.74) and 10.4 places (sophomores, r = 0.613), with 26 and 32.8 per cent wrongly classed¶

Claim · All claims
Evidence · 1 study · associational r1 · q2
Currency · newest study 1921 · not yet checked against its sources · not reviewed by a person

Subclaims¶

q2 i? For 54 college freshmen, the Thurstone and Brown University tests showed a median rank change of 6.7 places and correlation 0.74, with 26 per cent in the wrong class; for 64 sophomores the median change was 10.4 places, correlation 0.613, and 32.8 per cent wrongly classed. → Geyer 1921

Evidence¶

Geyer 1921¶

Geyer, D. L. (1921). The Reliability of Rankings by Group Intelligence Tests. The Journal of Educational Psychology. https://www.jstor.org/journal/jeduapsy

q2 · i? · associational · r1

Two test-administration comparisons in Normal College groups: 54 freshmen and 64 sophomores given the Thurstone and Brown University tests. The article prints correlations of 0.74 (freshmen) and 0.613 (sophomores) and wrong-class percentages of 26 and 32.8.

"The Thurstone and the Brown University tests when similarly given to 54 students of college freshmen grade showed a median change in rank of 6.7 places, as compared with a maximum possible change of 27 and a random change of 18."

Discussion¶

Related Claims¶

• Group intelligence scores correlated only modestly with school marks (freshmen: 0.41 Thurstone, 0.56 Brown; junior high: 0.25 Illinois, 0.32 Otis), which the author attributes to marks depending on many non-intelligence factors — related
• Correlations between two forms of the same test (up to 0.94, averaging 0.83 in Colvin's data) far exceed between-test correlations, casting doubt that different 'general intelligence tests' measure the same element — related
• Rankings of the same 120 junior high pupils by the Otis and Illinois group intelligence tests disagreed by a median of 18 places, with a rank correlation of 0.642 — related
• Dividing the 120 pupils into four class-sections by one test would place 51.6 per cent in the wrong section according to the other test — related