This article is cited in 2 papers

Short Communications

Nomograms for Probability Functions $\chi^2$

S. V. Smirnov, M. K. Potapov

Moscow

Abstract: In this paper a nomogram is constructed for the function
$$P(\chi^2,n)=\frac1{2^{(n-2)/2}\Gamma(n/2)}\int_\chi ^\infty z^{n-1}e^{-z^2/2}\,dz$$
of the variables, $P,\chi^2,n$ lying within the following limits:
$$1\leq n\leq110,\quad1\leq\chi^2\leq150,\quad0,001\leq P\leq0,999.$$
The relative error in the middle part of the answer scale of $P$ does not exceed $3\%$ for $0,1\leq P\leq0,9$ and $10\%$ at the ends of this scale.

Received: 26.02.1959

 English version: Theory of Probability and its Applications, 1961, 6:1, 124–126