Michael Rosenston is a fact-checker and researcher with expertise in business, finance, and insurance. Investopedia / Julie Bang A Z-test is a hypothesis test that helps an investor gauge the average ...

A one-sample z-test is the most basic type of hypothesis test. It is performed when the population means and standard deviation are known. This makes the analysis very simple. The main takeaway from ...

The z test is a commonly used hypothesis test in inferential statistics that allows us to compare two populations using the mean values of samples from those populations, or to compare the mean of one ...