Conclusions

Statistics is not about the method of science with its paradigm shifts and incommensurability; it is about investigating phenomena as they relate to populations of units. The statistical method as we have described is not the scientific method.⁶⁹ As fascinating as the questions raised in Section 5 might be, they are not our questions. That is a good thing; the empirical evidence to date suggests that they may not be resolvable.

The five stage PPDAC process with the associated language and sub-stages provides a good framework for describing investigations such as Michelson's, especially for people learning the intricacies of Statistics. More importantly, in actively planning and executing an empirical investigation, we believe that the framework is very valuable to ensure that important issues are at least considered. And this is the case for every statistical investigation.

Karl Pearson had it almost right. Whatever the case for science, we can say that the unity of Statistics consists alone in its method, not in its material. And it is this method that should be given the broadest dissemination.