Abstract This article is an attempt to throw more light on the problem of choosing plotting positions for the frequencies related to ordered sample values. The problem is particularly pertinent where special-scale graph paper is used such that a straight line indicates conformance of data to type of distribution assumed to apply. Such graph paper is often briefly referred to as "probability paper." The types of distributions here considered are the normal and the extreme-value distribution of Type I, with the accent on the extreme-value case. Various methods of determining plotting positions have been put forward and there is confusion of thought in judging what plotting convention is optimum. An optimum criterion proposed by Chernoff and Lieberman has received wide attention. Blom in a recent book develops further criteria 2. To clarify the problem the author has analyzed the purposes to be served in plotting data on probability paper. With a specific concept of the purpose to be served in mind, it becomes clearer to the investigator which plotting convention would be the best one to use.
Bradford F. Kimball (Thu,) studied this question.