Now, instead of using single expression values, we formulate null and alternative distributions using the average expression value from a sample that has spread σ/√n (ref. 4).

Step 1: Based on alpha and the alternative hypothesis, find a critical z-value or z-values (1.645 for the example). Step 2: Take the random sample and compute the sample mean, xbar (for example, ...

If the sample being tested falls into the one-sided critical area, the alternative hypothesis will be accepted instead of the null hypothesis. Financial analysts use the one-tailed test to test an ...