The fact that firms appear to be consistently heterogeneous (S.F.3) has brought Dosi to criticize the Neoclassical prediction that firms in an industry converge toward some kind of "optimal" or "representative" characteristic.Bottazzi, G., Cefis, E., Dosi, G. and Secchi, A., Invariances and Diversities in the Evolution of Manufacturing Industries, LEM Working Paper, 21, October, (2003) For such argument to be valid, the characteristics of firms would need to evolve in time toward a normal distribution, possibly showing some shrinking of the support. Notably, this theoretical implication poses an unresolved challenge to the arguments put forward by Milton Friedman in his essay The Methodology of Positive Economics. In such work Friedman asserted that maximizing behavior was a reasonable working approximation to describe the choices of economic agents:Friedman, M., The Methodology of Positive Economics, (1953), now in Essay in Positive Economics, University of Chicago Press, (1970). pp.17-23. in fact, even if not all economic agents actually maximize (for example because some make mistakes) only the "fittest" ones will be selected by the market. Therefore, those agents that actually maximize would be the only "survivors" to market selection, and hence they would gather very closely around the single optimal behavior. In other words, the tails of the distribution will tend to disappear as market selects the best "genes", which would turn out to be both "optimal" (in terms of fit to the market selection) and "representative" (since it would be the only surviving type). However, the empirical findings that constitute S.F.3 prove the exact opposite of Friedman's prediction: very different "genes" survive to the market. As a consequence, a realistic representation of economic behavior should rather allow for firm-specificities, which would explain the heterogeneity found in the data: a point that was clearly made by Richard Nelson and Sidney Winter in their book An Evolutionary Theory of Economic Change.Nelson, R.R. and Winter S.G., An Evolutionary Theory of Economic Change, Harvard University Press, Cambridge, MA, (1982). pp.72-136.
