In bargaining situations, buyers and sellers do not gauge offers solely at the light of their self-interested material gains, but also seem to take into account non-monetary considerations such as fairness or reciprocity. This paper attempts to quantify these non-monetary motives in a buyer-seller context. We fit a model to a simple negotiation game data to quantify the role of fairness considerations in negotiation behavior, and then use the model to obtain out-of-sample estimates of play in more complex, sequential negotiation games. The model embeds a social utility function, a probabilistic decision rule, and captures experience effects. The out-of-sample test data comes from 6 previously reported studies, encompassing 20 distinct parameterizations of the sequential negotiation game. The model is remarkably accurate with respect to directional findings and to out-of-sample estimates of average first offers, accounting for 95% of the variability in the data. Out-of-sample estimates of rejection behavior account for more than half the variability. The results suggest that the influence of non-monetary considerations on bargainer decision can be reliably quantified to predict negotiations outcomes.
DE BRUYN, A. et BOLTON, G. (2008). Estimating the Influence of Fairness on Bargaining Behavior. Management Science, 54(10), pp. 1774-1791.