Although Chhikara pointed out some of the severe limitations of the linear probability model, he was very kind to discriminant analysis models. The linear discriminant model is appropriate only if the explanatory variables are normally distributed. A high proportion of the financial ratios and other variables used in credit evaluation are not normally distributed. For example, most solvency ratios, such as percent equity, have a high proportion of the observations near one end of the range, a long tail in one direction, and a very short tail or no tail in the other direction. Given the non-normality of the distributions of many of the explanatory variables, discriminant analysis is clearly not an appropriate choice for most analyses. Continued use of discriminant analysis was justifiable when there were no good alternatives. But the development of a wide variety of logit and probit models, and the increase in computing power that makes maximum likelihood estimation of these models technically and financially feasible, have provided good alternatives. Future use of discriminant analysis in credit evaluation should be limited to situations where the authors clearly demonstrate that the explanatory variables have normal or near normal distributions. Further, tests of the performance of newly developed models should not use discriminant analysis results as the basis of comparison. Another important characteristic of the current state of the art is the pathetic level of understanding of misclassification costs. All of the models reviewed are explicitly or implicitly based on a minimization of misclassification costs. Clearly, the misclassification costs are not the same for all types of decisions. The costs of making a loan to a borrower who ultimately defaults are much different in both character and magnitude than the costs of not making a loan to a farmer who would be a good borrower. However, most of the models conducted to date, particularly those dealing with agricultural loans, have either ignored or assumed away the differences in misclassification costs. While this is
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