JIS Z 9053:1963

This Japanese Industrial Standard specifies the method of estimating the interval, which includes, with a probability, for example, of 95 %, the difference between two population means on the basis of the values obtained from the respective populations (or from a most representative lot thereof) when the standard deviations of the two populations are unknown. (Standard Deviations Unknown). The text of this standard describes the procedure for the case where two samples are equal in size and, at the same time, are considered ot have equal standard deviations. If otherwise, refer to Reference appended to the end of this standard.

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