We are going to explore ANOVA to test a hypothesis concerning more than two groups. ANOVA tell us if one group mean is distinct of others but it doesn't know which. We are going to run a ‘post-hoc analysis’.
We are going to use the diamonds dataset from ggplot2 package.
Our hypothesis are:
- Null Hypothesis: the mean of carat weight of the diamond is equal across all the quality cuts (Fair, Good, Very Good, Premium, Ideal)
- Alternative hypothesis: The mean carat is distinct in cuts.
Here we are import the dataset and see the three first rows: