Subjectivist (Bayesian) Theory

This chapter presents the third major view of probability and statistics, the subjectivist or Bayesian theory. The prior two chapters emphasized a linear theory proceeding from known to unknown. In contrast, the Bayesians emphasize updating beliefs, even beliefs that may not be “known,” but which provide a starting point in solving problems using probability and statistics. Like the frequentist theory, the Bayesian theory heavily depends on the use of data, or facts, that permit the Bayesians to contend that they have used facts in order to obtain adequate solutions to problems. Because both frequency theory and Bayesian theory have perceived successes, they vie with each other in present-day popularity as the two and only two viable views of probability and statistics. However, as with the frequency theory, the Bayesian method is inadequate for the purposes of this book because it assumes a convergence at infinity which will never be experienced.