Note that the correlation is higher for BB. To quickly get an idea of the uncertainty associated with this correlation estimate, we will fit a linear model and compute confidence intervals for the...

Note that the correlation is higher for BB. To quickly get an idea of the uncertainty associated with this correlation estimate, we will fit a linear model and compute confidence intervals for the slope coefficient. However, first make scatterplots to confirm that fitting a linear model is appropriate.

In Section 23.1 we learn about th the inner_join, which you can use to have the 2001 data and averages in the same table:

Compute the correlation between 2002 and the previous seasons for singles and BB.