Explanation:
According to the The Concise Encyclopedia of Statistics, the acceptance region is “…the interval within the sampling distribution of the test statistic that is consistent with the null hypothesis H0 from hypothesis testing.”
In more simple terms, let’s say you run a hypothesis test like a z-test. The results of the test come in the form of a z-value, which has a large range of possible values. Within that range of values, some will fall into an interval that suggests the null hypothesis is correct. That interval is the acceptance region.
