A random sample of 38 MLB (Major League Baseball) pitchers had an average velocity of 91.618 mph on fastballs with a standard deviation of 2.373 mph. Does the data suggest that the average velocity of a MLB pitcher's fastball exceeds 90 mph?
Added by Aaron A.
Step 1
- Alternative Hypothesis (H1): The average velocity of a MLB pitcher's fastball exceeds 90 mph (μ > 90). Show more…
Show all steps
Close
Your feedback will help us improve your experience
Sheryl Ezze and 96 other Intro Stats / AP Statistics educators are ready to help you.
Ask a new question
Labs
Want to see this concept in action?
Explore this concept interactively to see how it behaves as you change inputs.
Key Concepts
Recommended Videos
The average major league fastball is 92.0 miles per hour (mph). While there are many other factors other than velocity that are used to judge the quality of this pitch (location and movement, for example), velocity is a major factor in deciding whether a pitcher has "big league stuff." Suppose a scout is judging a college player and records the velocity of a random sample of 14 fastballs. Does the evidence imply that this pitcher has better than average major league "stuff" in regards to velocity?
Inferences on Two Samples
Putting It Together: Which Method Do I Use?
Among all Major League Baseball players, the mean speed of a four-seam fastball is 93.58 miles per hour (mph). The following data represents a random sample of four-seam fastballs thrown by David Price. Does the sample data suggest that David Price has a slower speed on his four-seam fastball? Use a significance level of 5%. 88.4 91.4 93.2 93.3 92.3 87.5 94.1 71.6 97.2 90.4 93.4 93.7 90.6 93.9 91.8 92.2 91.5 94.0 92.7 92.5
Jerelyn N.
Billy wants to test whether the average speed of his favorite pitcher's fastball differs from the league average of 92 miles per hour. He takes a sample of 36 of the pitcher's fastballs and computes a sample mean of 94 miles per hour. Assume that the standard deviation of the population is 4 miles per hour. a. Specify the null and alternative hypotheses to test Billy's claim. b. Calculate the value of the test statistic and the p-value. c. At the 5% significance level, can you conclude that Billy's favorite pitcher's fastball differs in speed from the league average? d. At the 1% significance level, can you conclude that Billy's favorite pitcher's fastball differs in speed from the league average?
Sri K.
Recommended Textbooks
Elementary Statistics a Step by Step Approach
The Practice of Statistics for AP
Introductory Statistics
Transcript
18,000,000+
Students on Numerade
Trusted by students at 8,000+ universities
Watch the video solution with this free unlock.
EMAIL
PASSWORD