## Thoughts on Teaching Week 11 tutorial

**Return to index of tutor information.**

### Thoughts on Sect. 11.3

If you count the dots on the scatterplot, you won't find \(n = 38\) dots, because of *overplotting*.
For example, there are two Corolla's from 2006 selling for $9500.

If you have time, you can ask students about this, and even ask for suggestions to improve this (such as jittering).

**Note**: since all the cars in the sample are second-hand, technically the results only generalise to second-hand cars, so that \(b_0\) really is the estimated price of a second-hand 2014 Corolla.

### Thoughts on Sect. 11.4

The point is that the same regression line can be associated with a high correlation, or a poor correlation.

Regression and correlation are not the same thing!

Regression and correlation are not the same thing!