The robustness of linear models for decision-making

This paper elaborates on some issues discussed by Moskowitz, who presented evidence that linear multiple regression models, estimated from decisions made by individuals, often outperform the individuals themselves. In discussing his results, Moskowitz (1) suggested that inconsistency in information utilization by individuals may account for the relative superiority of regression models, and (2) expressed concern over the robustness of linear regression models to changes in (a) information environments, (b) weighting parameters, and (c) functional form of the model. This paper discusses reasons (in addition to inconsistency) for the relative superiority of model over man, and it summarizes recent research in psychology concerning the robustness of linear regression models (and linear models in general). This paper is supportive, rather than critical, of Moskowitz's research.