Spencer Graves

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We derive an exponentially weighted moving average (EWMA) as the Bayesian prior mean for a random walk observed with normal error. This derivation shows how the weight on the last observation varies over time. This weight depends on the migration rate of the random walk and the noise variance, which can be estimated from reliability data and studies of gage(More)
Description The Adler data frame has 97 rows and 3 columns. The " experimenters " were the actual subjects of the study. They collected ratings of the apparent successfulness of people in pictures who were pre-selected for their average appearance. The experimenters were told prior to collecting data that the pictures were either high or low in their(More)
Modern products frequently feature monitors designed to detect actual or impending malfunctions. False alarms (Type I errors) or excessive delays in detecting real malfunctions (Type II errors) can seriously reduce monitor utility. Sound engineering practice includes physical evaluation of error rates. Type II error rates are relatively easy to evaluate(More)
When people are killed and property destroyed, the apparent perpetrators often make enemies. This and related observations are used in this article to describe new conceptual tools to help political and military leaders as well as concerned individuals distinguish between activity and productivity by (1) identifying likely short-and long-term consequences(More)
This chapter discusses a duality between the addition of random variables and the addition of information via Bayes' theorem: When adding independent random variables, variances (when they exist) add. With Bayes' theorem, defining " score " and " observed information " via derivatives of the log densities, the posterior score is the prior score plus the(More)
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