Current taxonomies of intelligence comprise two factors of mental speed, clerical speed (Gs), and elementary cognitive speed (Gt). Both originated from different research traditions and are conceptualized as dissociable constructs in current taxonomies. However, previous research suggests that tasks of one category can be transferred into the…

The excellent paper by Goldhammer (this issue) deals with a most relevant and very pervasive problem of ability assessment: the evaluation of performance by considering speed and accuracy of performance. Goldhammer proposes item-level time limits as a possible remedy for individual differences in the speed-accuracy trade-off (SATO) to keep time…

Studied the contribution of mental speed to task performance on reasoning tasks under timed and untimed conditions for 227 participants and for 90 participants working under time conditions. Results suggest that the use of speeded reasoning tests is likely to lead to overestimates of the relation between mental speed and reasoning ability. (SLD)