An Assessment of the Utility of Suicide Prediction*

ABSTRACT: Efforts to predict a future event assume varying levels of confidence depending on its base rate and the error rate of the prediction instrument. Most researchers working with suicide prediction instruments seem tacitly to assume they will be able to predict a future suicide most of the time. Applying basic decision theory on a neuropsychiatric hospital population indicates that researchers using a prediction schedule will be unlikely to predict a future suicide beyond a 20% level of efficiency. Contrary to the general clinical view, eliminating false negatives was shown to be more practical than eliminating false positives in increasing the efficiency of a predictive schedule.     

Equality, Envy, and the Sense of Injustice

This paper attempts to defend the value of equality against the accusation that it is an expression of irrational and disreputable feelings of envy of those who are better off. It draws on Rawls' account of the sense of justice to suggest that resentment of inequalities may be a proper resentment of injustice. The case of resentment of 'free riders' is taken as one plausible example of a justified resentment of those who benefit unfairly from a scheme of cooperation. Further examples then link the case of the free rider to other cases of unjust inequalities which are the appropriate objects of resentment and indignation.     

Towards a model theory of diagrams

A logical system is studied whose well-formed representations consist of diagrams rather than formulas. The system, due to Shin [2, 3], is shown to be complete by an argument concerning maximally consistent sets of diagrams. The argument is complicated by the lack of a straight forward counterpart of atomic formulas for diagrams, and by the lack of a counterpart of negation for most diagrams.The authors are grateful to Jon Barwise and an anonymous referee for valuable comments and suggestions.