On discrete distributions arising out of methods of ascertainment 论文

摘要

Non-observability of events. Certain types of events, although they occur may be unascertainable and the observed distribution would therefore be truncated. An example is the frequency of families with both parents heterozygous for albinism and having no albino children. There is no evidence that the parents are both hetero zygous unless at least one albino is born and the families with such parents and having no albino children get confounded with normal families. The actual frequency of the event ?zero albino children' is, thus, not ascertainable. Another example is the distribution of eggs laid by insects, where the frequency of zero eggs cannot be known.