A systematic evaluation of factors affecting referring expression choice in passage completion tasks

•De-contextualized stimuli show no effect of predictability on pronominalization.•Prompts embedded in stories do show an effect of predictability.•A rational speech act model can reconcile findings. There is a long-standing controversy around the question of whether referent predictability affects pronominalization: while there are good theoretical reasons for this prediction (e.g., Arnold, 2008), the experimental evidence has been rather mixed. We here report on three highly powered studies that manipulate a range of factors that have differed between previous studies, in order to determine more exactly under which conditions a predictability effect on pronominalization can be found. We use a constrained as well as a free reference task, and manipulate verb type, antecedent ambiguity, length of NP and whether the stimuli are presented within a story context or not. Our results find the story context to be the single important factor that allows to elicit an effect of predictability on pronoun choice, in line with (Rosa and Arnold, 2017; Weatherford and Arnold, 2021). We also propose a parametrization for a rational speech act model, that reconciles the findings between many of the experiments in the literature.