Drug stability studies are a mainstay of current methodological research in biostatistics. The major focus of this book concerns a certain statistic that plays a crucial role in constructing confidence bounds with a constrained explanatory variable. Although the form of the statistic is involved and cumbersome, its exact distribution was derived. It has been shown in this research that the statistic of the cut-off point for the optimal value has a very nice and simple distribution: a standard Cauchy distribution; in fact, amazingly, it has also been shown that this statistic is independent of...