EXAMPLE 20 Identifying the shape of a distribution
Student-Run Café Business
We return to the Student-Run café business data set first introduced in Example 8 on page 49 of Section 2.1. Figure 34 contains a histogram of the daily sales (in dollars) for the Student-Run café business. Identify whether the distribution is symmetric, right-skewed, or left-skewed.
Figure 2.34: FIGURE 34 Histogram of café business sales.
Solution
The histogram in Figure 34 has a vertical axis of symmetry (red vertical line). Although the two halves are not perfect mirror images of each other, they are close. In the real world, data are seldom perfectly symmetric, due to random variation. Thus, we can accept that the café business sales data are symmetric.
NOW YOU CAN DO
Exercises 79–82.