Contextual probability and word frequency as determinants of pauses and errors in spontaneous speech

This study investigated the relationship between the contextual probability of lexical items in spontaneous speech, as measured by the Cloze procedure, and word frequency. It also attempted to determine the relative importance of the two variables in causing delay, in the form of hesitation, in the production of spontaneous speech. The analysis revealed that content words of low contextual probability tended to be more infrequent than other words, and that both contextual probability and word frequency were associated with hesitation in speech. Contextual probability had an effect on hesitation even when word frequency was held constant, but word frequency had no effect when contextual probability was controlled. Analysis of certain types of errors, also, revealed that word frequency may play an important role in the lexical selection process.