In Exercise 29, we considered whether a linear model would be appropriate to describe the trend in

Question:

In Exercise 29, we considered whether a linear model would be appropriate to describe the trend in the number of passengers departing from the Oakland (CA) airport each month since the start of 1997. If we fit a regression model, we obtain this residual plot. We’ve added lines to show the order of the values in time:

a) Can you account for the pattern shown here?
b) Would a re-expression help us deal with this pattern?

Data From Exercise 29

The scatterplot below shows the number of passengers at Oakland (CA) airport month by month since 1997 (oaklandairport.com/news/statistics/passenger-history/).