ABSTRACT
This chapter is about the number of trials the people should take to test treatments to be able to make a use or not-use decision. Of course, any of several economic indices could be used. Typically, a company specifies a threshold value for the economic index, such as PBT, and only invests in the option if the calculated PBT is less than the threshold. The classic statistically based approach to determining the number of replicate trials in Stage 1 of the experimental plan, the pre-experimentation planning, does not consider the economics. A Bayes Belief method appears to be an appropriate method to make that determination. The number of replicate trials required to make either a statistical or economic decision depends on the variation of the trial outcome measurement and the user’s choice of T-I and T-II errors. .
