Hypothesis Testing

Hypothesis testing is a formal procedure for deciding whether the data give enough evidence to reject a default claim. You assume a “nothing interesting is happening” baseline, then ask: if that baseline were true, how surprising is the data I actually saw?

It works like a courtroom presuming innocence: you don’t prove the exciting claim true, you only check whether the boring baseline is implausible enough to abandon. Failing to reject the baseline is not proof it is true — it may just mean your sample was too small to detect a real effect.