On the Criterion that a Given System of Deviations from the Probable in the Case of a Correlated System of Variables is such that it Can Reasonably Be Supposed to have Arisen from Random Sampling

FIRST EDITION of one of the most important papers in the history of statistics, introducing the 'chi-squared' test of goodness of fit, "one of the most useful of all statistical tests" and "one of Pearson's greatest single contributions to statistical methodology" (DSB). "Specification or stochastic modeling of data is an important step in statistical analysis of data. Karl Pearson was the first to recognize this problem and introduce criterion, in a paper published in 1900, to examine whether the observed data support a given specification. He called it chi-squared goodness-of-fit test, which motivated research in testing of hypotheses and estimation of unknown parameters and led to the development of statistics as a separate discipline. In an article entitled "Trial by Number", [Ian] Hacking says that the goodness of fit chi-square test introduced by Karl Pearson (1900) 'ushered in a new kind of decision making' and gives it a place among the top 20 discoveries since 1900 considering all branches of science and technology" (C.R. Rao, "Karl Pearson Chi-Square Test: The Dawn of Statistical Inference"). In: Philosophical Magazine, Series 5, Vol 50, pp. 157-175. Complete volume (July-Dec 1900) offered. London: Taylor & Francis, 1900. Octavo, modern cloth. Provenance: with library stamp on volume title from the prestigious Gmelin Institute (after 1996, part of the Max Planck Institute). A fine copy.…