Chapter 9, Problem 8E

(a)

To determine

To explain in what ways is the relationship between run times and budgets similar for the three ratings groups.

Explanation of Solution

The scatterplot of the budget and run time is given in the question. In the scatterplot movies with R rating are in purple, those with PG- $13$ ratings are in red and those with PG rating are in green. Also the regression line is formed for the each group in the scatterplot. The relationship between run times and budgets is similar for the three ratings groups because the slopes of all the linear models are positive and a higher run time leads to a higher budget.

(b)

To determine

To explain how do the costs of R-rated movies differ from those of PG- $13$ and PG rated movies and discuss both the slopes and intercepts.

Explanation of Solution

The scatterplot of the budget and run time is given in the question. In the scatterplot movies with R rating are in purple, those with PG- $13$ ratings are in red and those with PG rating are in green. Also the regression line is formed for the each group in the scatterplot. The costs of R-rated movies differ from those of PG- $13$ and PG rated movies as while all three linear models have similar slopes, the budget of an R-rated movie is much lower than the other two because of the much lower starting budget. The slope of the graph is somewhat in the upward direction and the intercept is the is the budget in millions of dollars.

(c)

To determine

To explain how might that change your conclusions about PG- $13$ movies if it were omitted from this analysis.

Answer to Problem 8E

It does not change the conclusion.

Explanation of Solution

The scatterplot of the budget and run time is given in the question. In the scatterplot movies with R rating are in purple, those with PG- $13$ ratings are in red and those with PG rating are in green. Also the regression line is formed for the each group in the scatterplot. Now, if the film King Kong with a run time of $187$ minutes that is the red point sitting at the lower right of the scatterplot is omitted then it does not change the analysis of the PG- $13$ movies as the red point omitted is the outlier of the scatterplot so, it will not cause any change in the conclusion on the analysis.