null hypothesisnull hypothesis
An example of a null hypothesis is when you hypothesize that the wind blowing in from the open window was responsible for moving a rock across your desk; but, after testing, you find that wind blowing at the speed at which it was blowing could not move a rock of that size by itself.
(plural null hypotheses)
- (statistics) A hypothesis set up to be nullified or refuted in order to support an alternative hypothesis. When used, the null hypothesis is presumed true until statistical evidence in the form of a hypothesis test indicates otherwise. Therefore, the null and the alternative hypothesis must be mutually exclusive and exhaustive. The use of the null hypothesis is controversial.