The null hypothesis is proposed by a scientist before ... (Degrees of freedom, or df, will be explained in full later in this article.) However, in such cases, the test can be corrected by using ...

The neutral theory holds that most variation at the molecular level does not affect fitness and, therefore, the evolutionary fate of genetic variation is best explained by stochastic processes.

For a hypothesis to be put forward in science or engineering, the scientific method requires that one can test it. Scientists/engineers generally base hypotheses on previous observations that cannot ...