test statistic

A test statistic is a numerical value calculated from data during a hypothesis test. It's used to determine whether to accept or reject a specific assumption (the null hypothesis) about a population. The test statistic compares your observed data against what would be expected if the null hypothesis were true. Depending on its value, you can assess how unusual your data is, which helps you decide if the evidence is strong enough to support an alternative hypothesis. In essence, it’s a tool that quantifies the strength of the evidence in your data against the initial assumption.