On the explanation of the changes in age of the concentration of the death causes.

The high concentration of the diagnoses among the categories of death causes is called the concentration of death causes. The idea of diversity used in statistical ecology is in a sense a contrary concept. Introducing the investigation of diversity indices on epidemiological material, we have shown sexual differences and age characteristics of the latter. In the course of the investigations, there was an opportunity to measure exactly and analyse the high increase of the concentration of death causes at an older age. In this paper we related the changes due to age to the structure of the set of specific death rates and to that of hazard functions. According to our fitting investigations, the majority of the elements of the set of curves could be well approximated by the Gompertz or by the Weibull function. In this case, a mathematical explanation can be given to the increase, then decrease of Hill's diversity indices, that is, to the decrease, than increase of the concentration of death causes. Finally we point briefly to the evolutionary aspects of the discussed changes with age of this concentration.