Pretask and on-task adaptive design strategies for selecting number of instances in concept acquisition

A study with 67 undergraduates investigated design strategies for selecting number of instances needed in a concept learning task. Two strategies used adaptive procedures for the selection process, while a nonadaptive strategy selected instances by number of associated attributes. The data analysis showed that the full adaptive strategy (using pretask and on-task response data) required 25% less learning time and resulted in better posttest performance than the partial adaptive strategy (pretask data only). The partial adaptive strategy was 16% more efficient and demonstrated better performance than the nonadaptive strategy. An effectiveness ratio of 2 to 1 in favor of the full adaptive over the partial and nonadaptive strategies was obtained and illustrates the effect of using on-task data sources for instance selection. (19 ref) (PsycINFO Database Record (c) 2006 APA, all rights reserved).