- Check the conditions for Fisher’s Exact Test
- Explain the relationship of two qualitative binary variables using Fisher’s Exact Test
- Write out the null and alternative hypotheses.
- [latex]H_0[/latex]: The two variables are independent.
- [latex]H_A[/latex]: The two variables are not independent.
- Check the conditions for the hypothesis test.
- Independence/Randomness Condition: The sample from our population should be independent, random sample or independent sample that can be considered representative of the population.
- 2×2 contingency table: The variables for our study need to be categorical and binary, giving us two categories by two categories of data
- Calculate the test statistic.
- Calculate a [latex]P[/latex]-value.
- Compare the [latex]P[/latex]-value to the significance level, [latex]\alpha[/latex], to make a decision.
- Write a conclusion in context (e.g., we do/do not have convincing evidence…).
Now suppose that, instead of comparing black helmets to other colors, the researchers wanted to compare red helmets to other colors.