Knowledge base influences on judgments of frequency of occurrence

Chi and others have shown that a subject's knowledge base can have dramatic effects on cognitive tasks, sometimes reversing typical developmental differences. On the other hand, judgments of frequency-of-occurrence information have been shown to be immune to factors that typically affect memory. Kindergartners and adults judged frequency of well-known or unknown stimuli. Children were better able to judge frequency of occurrence of classmates than of famous adults (Experiment 1) or unknown children (Experiment 2). Similarly, adults were better able to judge frequency of occurrence of known adult faces than of unknown children (Experiment 1) or unknown adults (Experiment 3). The experiments reported here indicated that even an elementary process like frequency estimation is influenced by domain-specific knowledge of the stimuli.