Patterns of alignment in dialogue: Conversational partners do not always stay aligned on common object names

To examine communicative coordination on different linguistic levels we developed the Jigsaw Map Game, a flexible design permitting to investigate language processing in interactive conversation in a natural but controlled way. In an experiment on the locality of alignment effects an analysis of how partners apply object names in the course of the dialogues shows that 'easily coordinated' dialogues can lead to divergence of aligned representations: Partners sometimes get lexically aligned during conversation but later again drift apart ("anti-alignment"). Highly coordinated dialogues may under certain conditions be too easy seducing participants to introduce a greater variety of names in later stages of the conversation. We identify characteristics of smooth vs. problematic dialogues and discuss our results regarding criteria for efficient interactions. From a methodological point of view we additionally provide a quantification in terms of an alignment measure which abstracts from the operative level of linguistic alignment.