Skill and Knowledge Acquisition. Erlbaum, Hillsdale,

Recent theoretical developments in cognitive psychology imply both a need and a possibility for methodological development. In particular, the theory of problem solving proposed by Allen Newell and Herbert A. Simon (1972) provides the rationale for a new empirical method for the processing of think-aloud protocols--trace analysis. A detailed example is presented in which trace analysis is applied to human performance on a spatial reasoning task. The study, a portion of a larger study, involved 12 subjects who were required to solve a variety of spatial arrangement problems under different conditions. The protocol produced by a single subject--a 30-year-old female psychology student--while solving the block problems was selected for analysis on the basis of completeness and interest. The relations between trace analysis, on the one hand, and the psychometric ideas of measurement and standardization, on th