Chapter 5, Problem 34E

a)

To determine

To create an appropriate graphical display.

Explanation of Solution

Given:

  

Calculation:

Let us assume that, Group 1: American and Group 2: National.

Therefore, the data summary and boxplot for the average runs:

  

b)

To determine

To create an appropriate graphical display.

Explanation of Solution

Given:

  

The shape of the distribution of the American League is skewed to the right. While the shape of the distribution of National league is skewed to the left. The center of both leagues is same. The spread of the distribution of National league is higher than American league. There are no such outliers for both leagues. The small higher point is shown for National league.

c)

To determine

To whether 14 is extremely large run.

Explanation of Solution

Given:

  

Formula:

  $\begin{array}{l}IQR=Q_3-Q_1\\ Lower:Q_1-1.5\times IQR\\ Upper:Q_3+1.5\times IQR\end{array}$

First, we need to find upper and lower outlier limits.

  $\begin{array}{l}IQR=10.25-8.375=1.875\\ Lower:8.375-1.5\times 1.875=5.5625\\ Upper:10.25+1.5\times 1.875=13.0625\end{array}$

Therefore, 14 is above the upper outlier point. Hence, it is unusually high.