Given a data set about an individual or group (., interviewer ratings, life history or demographic facts, test results, self-descriptions), there are two modes of data combination for a predictive or diagnostic purpose. The clinical method relies on human judgment that is based on informal contemplation and, sometimes, discussion with others (., case conferences). The mechanical method involves a formal, algorithmic, objective procedure (., equation) to reach the decision. Empirical comparisons of the accuracy of the two methods (136 studies over a wide range of predictands) show that the mechanical method is almost.
