Null and alternative hypotheses
- We ask a question which provides a “null hypothesis”
(\(H_0\)) and collect
- Often: “there is no difference between two groups”
- Or: “there is no difference several subgroups”
- The alternative hypothesis is just the opposite of the null
hypothesis
- Data are gathered to comment on the null hypothesis
- The hypothesis is never truly proven/disproven, but data
can cast doubt on it
- The null hypothesis is finally accepted/rejected when a
preponderance of data have failed to cast doubt on it