KINE 305 Homework 2

Answer all questions below the question prompt. Show all math by typing in the steps.

Chapter 4

Answer questions 1 to 3 from the following information: Professor Jones has created a formula with which students can predict their grades on the final examination based on their total scores on the first two examinations. The prediction equation is ? = 2X + 30, where X is the total number of points a student has earned on the first two tests. The final examination has these characteristics: mean = 300 and standard deviation = 100. The correlation between total score on the first two tests and the final is .80. Kelly scored a total of 60 on the first two tests.

1.Predict Kelly's score on the final examination.

2.The line of best fit for predicting final examination score from number of practice problems completed is defined as ? = 10X + 40. Jamie completed 50 practice problems.What is Jamie's predicted score on the final examination?

Use the following information to answer #3 and #4:

Mean of Monday steps = 9725

Average steps per day = 10,594

s of Monday steps = 5700

s of average steps per day = 3000

Correlation between Monday and average steps per day = .80

Coefficient of determination = .64

The equation for predicting average steps per day from Monday steps is

? = .4X + 5000.

3.How many steps do you predict a person will average per day if he or she takes 3000 steps on Monday? Show your work.

4.Calculate the standard error of estimate for predicting average steps per day from Monday's steps.

Use the following information to answer items 5 and 6: Professor Kelly wants to develop a prediction equation to estimate final examination scores from a variety of class assignments (e.g., homework problems, study time, quizzes, midterm examination, class participation, book reports, number of absences).

The correlations that Professor Kelly obtained are listed here:

a. homework problems, r = -.30

b. study time, r = .60

c. quizzes, r = .58

d. midterm examination, r = .72

e. class participation, r = 1.10

f. book reports, r = .10

g. class absences, r = ?.78

5.Which single item should Professor Kelly use and why?

6.Place the correlations Professor Kelly has calculated in order from highest correlation to lowest.

7.An epidemiologist has found a strong positive correlation between the amount of time that children watch television and their 1.5 mi (2.4 km) run times. He argues for decreased time spent watching television to improve aerobic capacity in children. What is wrong with this logic?

8.What is the correlation between the X and Y coordinate points in figure 4.8 (p. 63)?Explain how you determined your answer.

Chapter 5

Use the following information to answer #9 - 14:

Researchers are interested in determining if there is a difference between two exercise regimens (regimen A and regimen B). The researchers think that the regimens may have differential effects on a treadmill test where the participants run to exhaustion. The researchers recruit 40 subjects to complete a 10-week study. Twenty subjects are placed into a group that will receive regimen A and 20 into a group that will receive regimen B. The researchers will evaluate the pre to post change in the dependent variable between the two groups.

9.Write the appropriate null hypothesis.

10.Write the alternative hypotheses.

11.What is the dependent variable in this study?

12.Describe what happens if the researchers make a type I error.

13.Describe what happens if the researchers make a type II error.

14.What is the most appropriate statistical test to analyze this study.

KINE 305 Homework 2 Answer all questions below the question prompt. Show all math by typing in the steps. Chapter 4 Answer questions 1 to 3 from the following information: Professor Jones has created a formula with which students can predict their grades on the final examination based on their total scores on the first two examinations. The prediction equation is = 2X + 30, where X is the total number of points a student has earned on the first two tests. The final examination has these characteristics: mean = 300 and standard deviation = 100. The correlation between total score on the first two tests and the final is .80. Kelly scored a total of 60 on the first two tests. 1. Predict Kelly's score on the final examination. 2. The line of best fit for predicting final examination score from number of practice problems completed is defined as = 10X + 40. Jamie completed 50 practice problems. What is Jamie's predicted score on the final examination? Use the following information to answer #3 and #4: Mean of Monday steps = 9725 s of Monday steps = 5700 Average steps per day = 10,594 s of average steps per day = 3000 Correlation between Monday and average steps per day = .80 Coefficient of determination = .64 The equation for predicting average steps per day from Monday steps is = .4X + 5000. 3. How many steps do you predict a person will average per day if he or she takes 3000 steps on Monday? Show your work. 4. Calculate the standard error of estimate for predicting average steps per day from Monday's steps. SEE Sy 1 r 2 SEE 3000 1 .80 2 SEE 3000 1 .64 SEE 3000 .36 SEE 3000 .60 1800 Use the following information to answer items 5 and 6: Professor Kelly wants to develop a prediction equation to estimate final examination scores from a variety of class assignments (e.g., homework problems, study time, quizzes, midterm examination, class participation, book reports, number of absences). The correlations that Professor Kelly obtained are listed here: a. homework problems, r = -.30 b. study time, r = .60 c. quizzes, r = .58 d. midterm examination, r = .72 e. class participation, r = 1.10 f. book reports, r = .10 g. class absences, r = .78 5. Which single item should Professor Kelly use and why? 6. Place the correlations Professor Kelly has calculated in order from highest correlation to lowest. 7. An epidemiologist has found a strong positive correlation between the amount of time that children watch television and their 1.5 mi (2.4 km) run times. He argues for decreased time spent watching television to improve aerobic capacity in children. What is wrong with this logic? 8. What is the correlation between the X and Y coordinate points in figure 4.8 (p. 63)? Explain how you determined your answer. Chapter 5 Use the following information to answer #9 - 14: Researchers are interested in determining if there is a difference between two exercise regimens (regimen A and regimen B). The researchers think that the regimens may have differential effects on a treadmill test where the participants run to exhaustion. The researchers recruit 40 subjects to complete a 10-week study. Twenty subjects are placed into a group that will receive regimen A and 20 into a group that will receive regimen B. The researchers will evaluate the pre to post change in the dependent variable between the two groups. 9. Write the appropriate null hypothesis. 10. Write the alternative hypotheses. 11. What is the dependent variable in this study? 12. Describe what happens if the researchers make a type I error. 13. Describe what happens if the researchers make a type II error. 14. What is the most appropriate statistical test to analyze this study