About a quarter of eighteen-year-old working children fall below the Yerkes normal-adult range on the Yerkes Point Scale¶

Claim · All claims
Evidence · 1 study · design r2 · q2
Currency · newest study 1915 · not yet checked against its sources · not reviewed by a person · overdue for a recheck since 1920: baselines and conditions change

Subclaims¶

q2 i? Of fifty unselected eighteen-year-old working children given the Yerkes Point Scale, 13 (26%) scored below 75 and 28 (56%) below 85, suggesting one fourth would be classed as mental defectives and a second fourth as borderline. → Woolley 1915

Evidence¶

Woolley 1915¶

Woolley, Helen Thompson. (1915). A new scale of mental and physical measurements for adolescents, and some of its uses. The Journal of Educational Psychology, 6(9), 521-550. https://doi.org/10.1037/h0075644

q2 · i? · design · r2

June 1915 comparison of fifty Yerkes Point Scale records with the authors' own percentile averages for the same working children. Correlation between the two systems was positive but not close: two low scorers on the authors' tests exceeded 85 on Yerkes, and three children below 75 on Yerkes were above the authors' median, all with foreign-born parents.

"we found that 13 of them, or 26%, fell below 75, while 28, or 56%, fell below 85. The distribution of this first fifty cases is as follows:"

Discussion¶

Related Claims¶

• Most referred children in the sample rated below their chronological age on both scales — related
• In the unselected county children's home population, the C. M. A. standard yielded 20.8% feeble-minded while the Three Per Cent. Hypothesis yielded 5.7%, with most children classified backward — related