IQs obtained by dividing mental by chronological age remain fairly constant up to the age of 14, which supports treating yearly increments of intelligence as equal absolute units up to about age 14.¶

Claim · All claims
Evidence · 1 study · theoretical r2 · q2
Currency · newest study 1917 · not yet checked against its sources · not reviewed by a person

Subclaims¶

q2 i? Successive testing of the same individuals shows IQs remain fairly constant up to age 14, which, given the constancy-of-brightness hypothesis, indicates equal absolute yearly increments of intelligence up to about age 14. → ARTHUK S. OTIS (Stanford University) 1917

Evidence¶

ARTHUK S. OTIS (Stanford University) 1917¶

ARTHUK S. OTIS (Stanford University). (1917). A Criticism of the Yerkes-Bridges Point Scale, with Alternative Suggestions. The Journal of Educational Psychology, Vol. VIII, No. 3. https://eric.ed.gov/?q=Otis+criticism+Yerkes-Bridges+point+scale

q2 · i? · theoretical · r2

The article reports, citing Terman and Stern, that IQs from successive testing of the same individuals remain "fahly constant up to the age of 14" (the article's spelling). Otis argues that, combined with his constancy-of-brightness hypothesis, this supports equal absolute increments of intelligence up to about age 14.

"Terman and Stern have found, however, by successive testing of the same individuals that I Q's gotten by dividing mental by chronological age do remain fahly constant up to the age of 14"

Discussion¶

Related Claims¶

• Children with the same chronological age and mental age pass more group tests in higher grades, an increase the author attributes to additional school experience — related
• The reviewer judges Goddard's book an optimistic, clear popular account that exaggerates intelligence's influence and omits technical questions such as IQ validity — related
• Yerkes-Bridges coefficients of intelligence of 1.20 or more are attained by very different percentages of children at successive ages (34.5% at ages 4-5 down to 0% at ages 16-17 and 18-on), so they do not represent the same degree of brightness at all ages. — related
• In the Yerkes-Bridges alteration of the Binet Scale, equal point increments are assigned to digit-span steps whose growth intervals, as placed in the Binet Scale, are approximately 1, 3, 3, and 4 years. — related
• IQ is only approximately constant across successive examinations, with first-to-fifth IQ correlation of +0.82 and prediction error of 4 to 7 points — related
• Psychological studies of children's endowments show schools must set different aims and materials for different classes of children, and have broken up lock-step promotion — related
• The reviewer reports that Baldwin's repeated examinations show the IQ is fairly constant though subject to fluctuations, and that repeated examinations exhibit a definite practice effect — a broader claim this one bears on