Is strategic knowledge of the balls & boxes puzzle implicit and unreportable?
S MOLEY & DC BERRY, University of Reading Two experiments examined evidence that strategic knowledge of the balls and boxes puzzle is implicit and unreportable (Reber & Kotovsky, 1997) and that concurrent think-aloud has a detrimental effect on performance as a result of overshadowing (Schooler, Ohlsson & Brooks, 1993). Experiment 1: 78 students (aged 18 to 27) participated in a 2x2x4 mixed design investigating whether ball labelling, reporting condition, and practice influenced problem-solving performance or the quality & quantity of explicitly reported strategic knowledge. Results showed that ball labelling had no effect, but practice significantly improved performance on all measures. Report writing after trial 1 overshadowed subsequent performance. Experiment 2: 39 students (aged 19 to 21) participated in a 2×3 mixed design investigating whether concurrent think-aloud overshadowed performance. No evidence of this was found, suggesting the verbalized knowledge was relevant. We concl
