Context effects on frequency judgments of words and sentences

A series of simple sentences (containing a single adjective, a noun, and a verb) were presented on a study trial. Presentation frequency of words comprising sentences was varied by presenting either repetitions of intact sentences or by recombining words from sentences for repetition in new sentences. Thus, modifiers (adjectives and verbs) accompanying repetitions of a given noun were either identical or different for each repetition. Following repetition of intact sentences, frequency judgments were higher when the whole sentences, rather than nouns from sentences, were employed as test items. Sentence frequency judgments were influenced by presentation frequency only when intact sen-tences were repeated. Increased spacing of intact sentence repetitions enhanced performance, regardless of the type of test item. The effect of increased spacing on noun frequency judgments was reduced by repeating nouns with different modifiers. Implications for a theoretical account of frequency discrimination are considered. Subjects are capable of judging the fre-quency with which a given item has been presented in an experimental setting, Ekstrand, Wallace, and Underwood (1966) proposed a theory that is based on S's ability to make frequency discriminations and demonstrated the adequacy of that theory to predict the effect of variables on verbal discrimination learning. A second source of evidence comes from experiments that required 5s to give numerical esti-mates of presentation frequency (Hintz-man, 1969; Underwood, 1969b); with a fair degree of accuracy, judged frequency was found to reflect actual frequency of presentation. The present investigation is concerned with the nature of the memory representation that serves as a basis for frequency judgments. Underwood (1969a) has suggested that presentation frequency is encoded as an attribute of memory. Repetitions are assimilated to produce a single frequency attribute which is the basis for frequency judgments. This position implies a direc