Abstract: | ![]() Thirty-six four-year-old children of each sex were tested in a two-choice marble dropping task. There were three Ss in each cell of a 3 × 2 × 2 × 2 factorial design. The factors investigated were: reinforcement condition (Contingent, Yoked, Nonreinforcement), sex, base preference level (strong vs weak), Base Rate Level (high vs low). The dependent variables were: base preference ratio, base rate, preference ratio change, rate change. The contingently reinforced Ss had significantly higher preference change scores than Ss in the other two reinforcement conditions but only at the high base preference level. The Ss in both the contingent and yoked groups had higher rate change scores than Ss in the nonreinforcement group. The results were interpreted as indicating social reinforcement may have two effects, one a cue function and the other an effect on S's motivational system. The results indicate that regression effects do not operate in the two-choice task and that crossing baseline levels of performance is an effective way to control baseline differences in analyses of change in the two-choice task. |