UNPRIMED STEM COMPLETION IS ONLY MODERATELY PREDICTED BY WORD-FREQUENCY AND LENGTH

Factors that determine unprimed performance in word-stem completion we re investigated. Researchers' descriptions of materials used in word-s tem completion suggest that normative word frequency, number of altern ative completions, and response length are believed to be important. A total of 160 students provided normative responses to each of 914 mul tiple-completion three-letter word stems, resulting in over 12,000 uni que responses. Although the number of alternative responses made corre lated well with the number possible, word frequency and length were ex tremely variable in their relation to response frequency across stems. Creating more precise materials for implicit memory studies appears t o require consulting normative response data.