The Mathematical Theory Of Probabilities And Its Application To Frequency Curves And Statistical Methods Volume 1 PDF Download

Excerpt from The Mathematical Theory of Probabilities, Vol. 1: And Its Application to Frequency Curves and Statistical Methods Mr. Fisher has requested that an introduction be written to this, the second edition of his work on probabilities, which shall indicate some of the practical applications of the mathematical theory with which his treatise deals. The writer has only a limited knowledge of mathematical technique - yet it has so happened that in twenty-five years of active work as engineer, statistician and executive he has had frequent occasion to call upon the skill of trained mathematicians for the solution of practical problems involving frequency curves and probabilities. Among such mathematicians none has been more helpful, or quicker to perceive the possibility of making valuable applications of higher mathematics to business problems, than Ir. Fisher himself. For this reason it is a duty as well as a privilege to outline, at his request, certain actual practical experiences with mathematical applications and to indicate such possible applications for the future. The writer's initial experience with frequency curves and probabilities was in the j-ears 1902 and 1903, when it became evident, in analyzing various problems in telephone traffic, that certain peak loads, which were superimposed upon the normal seasonal, weekly, and daily fluctuations, could be accounted for only by the laws of chance. Recourse was, therefore, had to the formulæ then available for approximate summations of the terms of the binomial expansion, and from these a series of curves was drawn which indicated for an given normal hourly traffic (as indicated by studies of seasonal, weekly, and daily variations) the probability that any given short period load would be equalled or exceeded. Practical experience with these curves soon showed that, in spite of minor errors, they were close enough to the real facts to make them of primary importance in traffic studies of all kinds, and particularly in the development of mechanical switching devices. Their use for such purposes has now become a commonplace in telephone engineering. As a by-product of the preceding application there have been other interesting uses of the same probability curves. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.