Both thematic role and next-mention biases affect pronoun use in Dutch

An important question is whether speakers consider listeners’ expectations when choosing whether to use a pronoun. It has been suggested that certain thematic roles are more expected to be mentioned again, and are therefore more likely to be pronominalized. In the present study, we aim to disentangle predictability effects on pronoun use from thematic-role effects. To this end, we conducted two web-based continuation experiments in Dutch, in which the next-mention biases associated with Source-Goal and Agent-Patient verbs were manipulated to create a shift in the bias. Experiment 1 confirmed that the manipulations changed the biases. Experiment 2 showed that while thematic role mainly influenced demonstrative and full pronoun use for non-subjects, next-mention biases played a role in the choice between reduced and full pronouns and between pronouns and full NPs, irrespective of thematic role or grammatical function. Thus, thematic role and predictability seem to affect pronoun use in different ways.