Cue-Response Correlations in the Attainment of a Scalar Concept

The usual study of concept attainment involves a classificatory concept. E divides a collection of stimuli into two classes on the basis of the presence or absence of certain characteristics, and S is asked to discover the "concept" or basis for classification. A smaller number of studies have employed a scalar concept. E assigns a scale value to each stimulus in the collection by applying some rule to the numerical values of selected attributes; S is asked to learn to rate stimuli on this scale. To succeed on the classificatory problem, S has to determine which of the attributes are relevant and what conjunctive or disjunctive combination of attribute-values is common to the positive instances of the concept. To succeed on the scalar problem, S has to identify relevant attributes and find a way of combining the information into an estimate of the scale-value assigned by E. One might regard the classificatory problem as requiring a response on a two-valued scale; each response is either right or wrong. From this point of view, the scalar concept is a more general case. The present study examines how Ss use multiple cues in solving a scaledconcept problem. The desired response to each stimulus corresponds to a weighted sum of certain cue-variables. S is required on each trial to estimate the scale-value assigned to the stimulus by the (unknown) rule; he is then told the correct value.