The main ideas with EDA are the exploration of the variables.

• Centers - means, medians
• Variation - standard deviations, ranges
• Outliers
• Missing Values
• Covariation, Correlation

• Two categorical variables - Contingency Tables, Chi-Square Tests
• One categorical variable and one Numeric variable - Side-by-side boxplots, T-tests, One-way ANOVA
• Two numeric variables - Scatterplots, Correlation, Regression, Smoothing

What does the correlation coefficent measure?

The correlation coefficient \(r\) measures the strength and direction of the linear relationship between two quantitative/numeric variables.