03. Setting Up Hypothesis Tests - Part I

In this video, you learned a few rules for setting up null and alternative hypotheses:

1. The $H_0$ is true before you collect any data.
   
   
2. The $H_0$ usually states there is no effect or that two groups are equal.
   
   
3. The $H_0$ and $H_1$ are competing, non-overlapping hypotheses.
   
   
4. $H_1$ is what we would like to prove to be true.
   
   
5. $H_0$ contains an equal sign of some kind - either =, $\leq$, or $\geq$.
   
   
6. $H_1$ contains the opposition of the null - either $\neq$, $>$, or $<$.

You saw that the statement, "Innocent until proven guilty" is one that suggests the following hypotheses are true:

$H_0$: Innocent

$H_1$: Guilty

We can relate this to the idea that "innocent" is true before we collect any data. Then the alternative must be a competing, non-overlapping hypothesis. Hence, the alternative hypothesis is that an individual is guilty.