Sample spaces, distributions, estimators …

In the following sections, we present a large body of theory which still is in its infancy. We could have strived at rigor, generality and completeness but, then, we would have stuck halfway in conjectures. The main issues are not yet clear. For simplicity, we have decided to restrict ourselves to what we need, leaving to the experts the task of extending and improving the main arguments. We hope that, sooner or later, some motivated analysts highly qualified in topology will sustain the investigations by von Mises and Prokhorov. We ourselves resort to the elementary tools of mathematical analysis.