=Z.TEST(array,x,[sigma])
=ZTEST(A2:A11,4)
The ZTEST function in Sourcetable is used to test the deviation of a dataset from a hypothesized population mean. For example, let's assume we have a data set of 10 values: A2:A11. We can use the ZTEST function to calculate the one-tailed probability-value of a z-test for the data set at the hypothesized population mean of 4. This will return the probability-value of 0.090574.
=2 * MIN(ZTEST(A2:A11,4), 1 - ZTEST(A2:A11,4))
We can also use the ZTEST function to calculate the two-tailed probability-value of a z-test. To do this, we use the same data set as in example 1, but we enter the preceding formula into the cell. This will return the two-tailed probability-value of 0.181148.
=ZTEST(A2:A11,6)
We can also use the ZTEST function to calculate the one-tailed probability-value of a z-test for the data set at a different hypothesized population mean. For example, if we hypothesize that the population mean is 6, use this example, and will return the probability-value of 0.863043.
The ZTEST function is a statistical tool that calculates the probability that the sample mean is greater than the average of observations in the data set. It offers improved accuracy compared to other tests.