\ ˈzē-ˌtest How to pronounce z-test (audio) \

Definition of z-test

: any of several statistical tests that use a random variable having a z distribution to test hypotheses about the mean of a population based on a single sample or about the difference between the means of two populations based on a sample from each when the standard deviations of the populations are known or to test hypotheses about the proportion of successes in a single sample or the difference between the proportion of successes in two samples when the standard deviations are estimated from the sample data

First Known Use of z-test

1951, in the meaning defined above

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The first known use of z-test was in 1951

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Cite this Entry

“Z-test.” The Merriam-Webster.com Dictionary, Merriam-Webster Inc., https://www.merriam-webster.com/dictionary/z-test. Accessed 9 December 2019.

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