Simulating the referential properties of Dutch, German and English Root Infinitives in MOSAIC

Children learning many languages go through an Optional Infinitive stage in which they produce non-finite verb forms in contexts in which a finite verb form is required (e.g. ‘That go there’ instead of ‘That goes there’). MOSAIC (Model of Syntax Acquisition in Children) is a computational model of language learning that successfully simulates the developmental patterning of the Optional Infinitive (OI) phenomenon in English, Dutch, German and Spanish (Freudenthal, Pine, Aguado-Orea & Gobet, 2007). In the present study, MOSAIC is applied to the simulation of certain subtle but theoretically important phenomena in the cross-linguistic patterning of the OI phenomenon that are typically assumed to require a more complex formal analysis. MOSAIC is shown to successfully simulate 1) The Modal Reference Effect: the finding that Dutch and German children tend to use Root Infinitives in modal contexts, 2) The Eventivity constraint: the finding that Dutch and German Root Infinitives refer predominantly to actions rather than static situations, and 3) The absence or reduced size of these effects in English. These results provide strong support for input-driven explanations of the Modal Reference Effect as well as MOSAIC’s mechanism for producing Root Infinitives, and the wider claim that it is possible to explain key aspects of children’s early multi-word speech in terms of the interaction between a resource-limited distributional learning mechanism and the surface properties of the language to which children are exposed