Equal Prior Probabilities Research Articles

A Bayesian prediction of multiple-look identification performance from one-look data: The effect of unequal prior probabilities

Bayes’s theorem had accurately predicted multiple-look visual identification performance from one-look data in two previous studies when the prior probabilities of the visual stimuli were equal. In this study, prior probabilities were manipulated to determine whether these values were important in determining agreement between man and statistical man. The prior probabilities of the stimuli, four gap orientations in Landolt rings, were .7, .1, .1, and .1 for four Ss and .3, .3, .3, and .1 for three Ss. One-look data were used to predict two-look and four-look performance. In the 7-1-1-1 condition, the empirical percent correct increased as a function of repeated observations for the rare stimuli, but not for the high-probability stimuli. In the 3-3-3-1 condition, Ss improved over repeated observations for both types of stimuli. Predictions of multiple-look performance under unequal prior probability conditions in this study were less accurate than those under equal prior probability conditions in previous studies. Three possible determinants of this difference were discussed.

A Pareto optimal group decision process: A reply

I am encouraged by Miss Eysenbach's note. First, by not recognizing as conventional the assumption of equal prior probability distributions of systemrelevant events between individuals, she joins a group of others who have indicated to me that it was neither recognized nor demonstrated--before my footnote 5--that the assumption of equal probability distributions of market prices between individuals was necessary for the Pareto optimality of the standard competitive process in an all-private-goods world with transaction (including market information) costs. Second, she has shown (in her Section II) that the optimal solution produced by the D-Process would not be altered if we allowed an individual in the system to have perfect foresight. This last result clearly lends an element of robustness to a D-Process solution which I had not even conjectured. Finally, she, for one, has apparently understood my D-Process paper much better than she has the voluntary contributions literature.