Proceedings of the Annual Meeting of the Cognitive Science Society

We propose an extension to probabilistic pragmatic models to include a dimension that allows for the modeling of argu-mentative language use. Within our extended Rational Speech Act model, argumentative strength stands for a statisticalmeasure of observational evidence which impacts a speakers utterance choice. More concretely, our model recasts speakerutility in terms of a weight parameter which varies between being purely informative and purely argumentative. We fitthe extended RSA model to empirical data from a novel production experiment. Our initial results suggest that there isroom for argumentativity on top of informativity in formalizations of pragmatic language reasoning. Crucially, we see thatthe relationship between the two is not straightforward, as the model fails to capture instances of human behavior whichare more manipulative than expected by the suggested informativity-argumentativity trade-off. All in all, our explorationprovides us with interesting insights about this relationship.