Question

Which data analysis method is more appropriate: paired data difference in means or difference in means with two separate groups? In 1969, the height of Major League Baseball pitching mounds was lowered from 15 to 10 inches. This decreased a pitcher's leverage and presumably the speed of a typical fastball. Fifteen Major League pitchers were selected at random, and each threw his best fastball from a 15 -inch mound and from a 10 inch-mound. The speed of each pitch (in mph) was recorded. We want to estimate the difference in the speeds of fastball pitches for the two heights of mounds

Answer 1

The appropriate data analysis method for comparing fastball speeds thrown from two different mound heights by the same pitchers is the paired data difference in means using a paired samples t-test.

Step-by-step explanation:

When comparing the speeds of baseball pitches thrown from different mound heights by the same group of pitchers, the most appropriate data analysis method is the paired data difference in means. This is because each pitcher throws from both the 15-inch mound and the 10-inch mound, and therefore, the two samples of pitch speeds are not independent. The paired samples t-test can be used to estimate the difference in means of the speeds for the two different mound heights. Each pitcher's throw from the 15-inch mound is paired with their throw from the 10-inch mound, and the differences are analyzed to determine if there is a statistically significant difference in the speeds.