The digit series used was too short, with 73 of 970 trials reaching the maximum score of ten¶

Claim · All claims
Evidence · 1 study · associational r2 · q2
Currency · newest study 1918 · not yet checked against its sources · not reviewed by a person

Subclaims¶

q2 i? 73 of the 970 trials produced a Maximum Series score of 10, leading the author to conclude the series should have been extended to at least twelve digits. → Mitchell 1918

Evidence¶

Mitchell 1918¶

Mitchell, David. (1918). Variability in Memory Span. The Journal of Educational Psychology. https://www.google.com/search?q=%22Variability+in+Memory+Span%22+Mitchell+1918

q2 · i? · associational · r2

Frequency analysis of the 970 trials made by the 97 children tested on ten successive days. The article reports that "73 out of the 970 trials result in a "Maximum Series" score of 10" and that the series should have been lengthened.

"We find that 73 out of the 970 trials result in a "Maximum Series" score of 10. It is obvious from these results that the series should have been increased in length to at least twelve, and possibly a higher number."

Discussion¶

Related Claims¶

• Lengthening the interval between dictated digits markedly lowered children's memory span scores on one testing day — related
• Test-retest correlations of memory span are low, questioning the validity of a single memory span test — related