Alternative Hypothesis
The alternative hypothesis, Ha, is a statement of what a statistical hypothesis test is set up to establish.[1]
The null hypothesis (denoted H0) is a statement about the population statistic, such as µ.
The alternate hypothesis (denoted Ha) is a claim to be tested.
Science, in general, operates by disproving unsatisfactory hypotheses and proposing new-and-improved hypotheses which are testable. The approach we take in statistics is exactly this scientific method. We start with a hypothesis which we assume is correct. We call this the null hypothesis or H0, and our goal is to reject H0 in favor of the alternative hypothesis, Ha.[2]
Ha can also be denoted as H1.
