A hypothesis test is a statistical procedure used to make decisions or inferences about a population characteristic based on a sample of data. Its purpose is to evaluate the truthfulness of a statement (hypothesis) regarding a population parameter (for example, variance).
Null Hypothesis (\( H_0 \)): It is a specific statement about the population parameter that is assumed to be true at the beginning of the test. It represents the "no change" or "no effect" state.
Alternative Hypothesis (\( H_1 \)): It is a statement contrary to the null hypothesis and represents the effect that is being investigated or tested.