In each exercise,
- (a) identify the claim and state H0 and Ha.
- (b) find the critical value and identify the rejection region,
- (c) find the test statistic,
- (d) decide whether to reject or fail to reject the null hypothesis, and
- (e) interpret the decision in the context of the original claim.
In Exercises 1–3, use the data, which list the hourly wages (in dollars) for randomly selected respiratory therapy technicians from three states. Assume the wages are
Maine: 20.92, 25.37, 23.06, 15.64, 27.72, 24.90, 19.26, 23.46, 18.49, 21.76, 22.36
Oklahoma: 22.70, 19.95, 17.85, 16.76, 21.32, 18.96, 17.99, 28.35, 25.30, 21.93
Massachusetts: 25.43, 23.21, 30.81, 26.62, 31.42, 31.34, 34.58, 28.22, 27.25, 22.83, 27.45, 27.71
1. At a = 0.05, is there enough evidence to conclude that the variances of the hourly wages for respiratory therapy technicians in Maine and Massachusetts are the same?
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Elementary Statistics: Picturing the World (7th Edition)
- Major League Baseball (MLB) consists of teams that play in the American League and the National League. MLB collects a wide variety of team and player statistics. Some of the statistics often used to evaluate pitching performance are as follows: ERA: The average number of earned runs given up by the pitcher per nine innings. An earned run is any run that the opponent scores off a particular pitcher except for runs scored as a result of errors. So/IP: The average number of strikeouts per inning pitched. β’ HR/IP: The average number of home runs per inning pitched. β’ R/IP: The number of runs given up per inning pitched. The following data show values for these statistics for a random sample of 20 pitchers from the American League for a season. Player Team ERA SO/IP HR/IP R/IP Verlander, J DET 24 2.39 1.01 0.10 0.30 Beckett, J BOS 13 7 2.90 0.91 0.10 0.34 Wilson, C TEX 16 7 2.95 0.92 0.06 0.39 Sabathia, C NYY 19 8 3.00 0.98 0.08 0.37 Haren, D LAA 16 10 3.18 0.82 0.07 0.38 McCarthy, B OAK 9β¦arrow_forwardMajor League Baseball (MLB) consists of teams that play in the American League and the National League. MLB collects a wide variety of team and player statistics. Some of the statistics often used to evaluate pitching performance are as follows: Β ERA: The average number of earned runs given up by the pitcher per nine innings. An earned run is any run that the opponent scores off a particular pitcher except for runs scored as a result of errors. SO/IP: The average number of strikeouts per inning pitched. HR/IP: The average number of home runs per inning pitched. R/IP: The number of runs given up per inning pitched. Β The following data show values for these statistics for a random sample of 20 pitchers from the American League for a season. (chart attached in image) Β Β a. What are the values ofΒ Β andΒ Β (to 3 decimals), if the average number of runs is the dependent variable and the average number of strikeouts per inning pitched and the average number of home runs per inning pitchedβ¦arrow_forwardMajor League Baseball (MLB) consists of teams that play in the American League and the National League. MLB collects a wide variety of team and player statistics. Some of the statistics often used to evaluate pitching performance are as follows: ERA: The average number of earned runs given up by the pitcher per nine innings. An earned run is any run that the opponent scores off a particular pitcher except for runs scored as a result of errors. SO/IP: The average number of strikeouts per inning pitched. HR/IP: The average number of home runs per inning pitched. R/IP: The number of runs given up per inning pitched. The data in the Excel Online file below show values for these statistics for a random sample of 20 pitchers from the American League for a season. Construct a spreadsheet to answer the following questions.arrow_forward
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