Question

a researcher sets the following criterion: when the probability of obtaining a given value of the sample mean if the null hypothesis were true is less than 5%, we reject the value stated in the null hypothesis. what is the 5% criterion called?

Answer 1

Answer: The 5% criterion mentioned in the given statement is called the level of significance or alpha level. In hypothesis testing, the level of significance or alpha level is the maximum allowable probability of making a type I error, i.e., rejecting the null hypothesis when it is true. It is usually set at 0.05 or 5%, but it can be set at any value between 0 and 1 depending on the researcher's choice. The alpha level helps to determine the critical region, which is the set of values of the test statistic that would lead to the rejection of the null hypothesis at the specified level of significance.