# Null Hypothesis and Statistical procedures for wing to rotary wings aircraft data. Null Hypothesis, Alternative Hypothesis, Significance Level, Critical Value, P value are included in the solution.

Null Hypothesis and Statistical procedures.

1. You are in charge of the training program for pilots transitioning from fixed wing to rotary wings aircraft. You are considering the purchase of a simulator for initial training, but you are unsure if the quality of the simulator training will be worth the expenditure. You have access to data from another command similar to your own who has been using simulator training, and you want to compare the time that it took pilots to meet standards for rotary wing for those who initially were trained in the simulator (Command A) and those who were not (Command B). The times for meeting standards in terms of days are listed below.

Command A Command B

28 35

32 40

29 28

24 36

19 35

21 34

23 36

a. What is the null hypothesis?

b. What statistical procedure will you use?

c. Which Command has the better times? Is this statistically significant? Support your answer with statistical evidence.

2. A recent report claims that 45% of enlisted personnel who have spent at least four years and no more than ten in the service complete a bachelor's degree, 25% complete some college work, 15% do not seek additional college-level training, and 15% are not accounted for. You want to see how the frequencies found in the population compare with a particular local Navy base, so you take a simple random sample of 500 enlisted sailors who have completed between four and ten years in the Navy. You find that 275 completed a college degree, 88 have completed some college work, 37 have not sought additional college-level training, and the rest of the sailors are not accounted for. How does your sample compare to what you expected to find?

a. To see how your local Naval base compares to the report of all enlisted personnel, you will use a

b. State the null hypothesis.

c. Show the statistics for the test you have chosen.

d. Are the results statistically significant? Why or why not?

3. You are concerned that airport managers may not be receiving enough quantitative instruction in current aviation management degree programs. Specifically, you want to know if Embry-Riddle graduates possess sufficient quantitative skills to conduct the mathematical analyses needed for making superior decisions regarding the management of airports. You decide to see if there is any difference between the quantitative scores of airport management graduates from Embry-Riddle and the scores of airport management graduates from other institutions on the GMAT.

ERAU School A School B School C

580 500 530 450

550 480 560 500

490 575 430 420

550 350 450 580

430 450 500 450

a. What type of test would you use?

b. What was the average score for ERAU graduates?

c. What is the value of the test statistic? The significance level?

d. Are the results statistically significant?

4. A total of 60 flight students were instructed at SimuFly Flight School. A total of 30 students were taught by a live instructor in a real plane for all of their instructional flight time. The other half of the students were taught by a live instructor in a real plane for half of their instructional flight time and learned in a simulator for half of their instructional flight time. A sample of 15 students who learned with the live instructor (Group 1) and a sample of 15 students who learned with both live instruction and in a simulator (Group 2) were selected to complete a questionnaire. All 30 completed the survey.

5 item survey

1=strongly disagree; 2=disagree; 3=neutral; 4=agree; 5=strongly agree

1. I would like to take more flight instruction with simulation.

2. I feel well prepared to perform the maneuvers taught.

3. I learned as well with simulation as with live instruction.

4. I felt confident during the final flight.

5. The simulated flights felt realistic.

a. What is the Null Hypothesis?

b. What is your Research Hypothesis?

c. What statistical test did you use and why

d. Show the statistics for the test you have chosen.

e. Are your results statistically significant?

Data Set for Problem 4

Responses for Group 1

Student Item 1 Item 2 Item 3 Item 4 Item 5

1 3.00 4.00 2.00 2.00 2.00

2 3.00 3.00 2.00 4.00 2.00

3 4.00 5.00 2.00 3.00 2.00

4 4.00 2.00 4.00 5.00 2.00

5 4.00 3.00 3.00 2.00 2.00

6 4.00 3.00 5.00 3.00 2.00

7 4.00 3.00 2.00 3.00 4.00

8 5.00 3.00 3.00 3.00 3.00

9 5.00 3.00 3.00 3.00 5.00

10 2.00 3.00 3.00 3.00 2.00

11 2.00 3.00 3.00 3.00 3.00

12 4.00 3.00 3.00 3.00 3.00

13 3.00 4.00 3.00 3.00 3.00

14 5.00 4.00 3.00 4.00 3.00

15 2.00 4.00 3.00 4.00 3.00

Responses for Group 2

Student Item 1 Item 2 Item 3 Item 4 Item 5

1 3.00 4.00 4.00 4.00 3.00

2 3.00 4.00 4.00 4.00 3.00

3 3.00 4.00 4.00 4.00 3.00

4 3.00 4.00 4.00 4.00 4.00

5 3.00 4.00 4.00 4.00 4.00

6 3.00 5.00 4.00 4.00 4.00

7 3.00 5.00 4.00 5.00 4.00

8 3.00 5.00 4.00 5.00 4.00

9 4.00 5.00 5.00 5.00 4.00

10 4.00 5.00 5.00 5.00 4.00

11 4.00 5.00 5.00 5.00 4.00

12 4.00 3.00 5.00 5.00 5.00

13 4.00 3.00 5.00 3.00 5.00

14 4.00 4.00 5.00 3.00 5.00

15 4.00 3.00 3.00 4.00 5.00

5. The city of Daytona Beach was concerned that a new ordinance which had raised the beach driving fee might have a negative impact on tourism. The city has engaged you to investigate this problem. You gathered data from 20 different days (10 before and 10 after) reflecting the number of vehicles on the beach before and after the ordinance, taking care to control for weather conditions and other variables as much as possible.

Data

Day Vehicles on the beach before the new ordinance Day Vehicles on the beach after the new ordinance

8-1-03 221.00 8-1-04 245.00

8-2-03 222.00 8-2-04 222.00

8-3-03 343.00 8-3-04 333.00

8-4-03 234.00 8-4-04 111.00

8-5-03 112.00 8-5-04 444.00

8-6-03 221.00 8-6-04 111.00

8-7-03 222.00 8-7-04 111.00

8-8-03 343.00 8-8-04 222.00

8-9-03 234.00 8-9-04 123.00

8-10-03 112.00 8-10-04 123.00

a. State the null hypothesis.

b. What test did you use?

c. State the results. Are they statistically significant?

6. The flight department wanted to test the effectiveness of their new flight scheduling software. They gathered data from the twelve months before the installation and the twelve months after implementation of the new software. For ease of analysis the data are presented as the mean number of cancellations for each month.

a. What is the null hypothesis?

b. What test did you use? Why?

c. What did you find?

d. Write up your results using scientifically recognized form.

Data Set

Month 2003 2004

1 15 15

2 22 9

3 12 9

4 21 10

5 9 5

6 13 10

7 10 6

8 24 19

9 26 7

10 14 15

11 23 4

12 15 3

7. The production manager of an aircraft repair facility is interested in determining the effects of several variables on production. One set of data he collected from a randomly sampled portion of his production force. The data consists of production figures based on a standard production of 100, number of toilet breaks and beverage consumption during work.

SUBJECT TBREAK BEVCONSMP PRODUCTION

1 2 3 98

2 3 5 96

3 1 3 98

4 2 4 97

5 3 5 95

6 4 6 94

7 1 1 101

8 3 6 94

9 1 2 97

10 2 3 97

11 2 3 97

12 3 5 96

13 1 3 98

14 2 4 97

15 2 4 96

16 3 5 98

17 3 5 96

18 4 6 94

19 1 1 100

20 1 1 101

21 4 6 93

22 3 5 96

23 2 4 97

24 2 3 97

25 3 5 96

26 2 3 97

27 1 1 100

28 2 4 96

29 1 1 101

30 4 5 93

a. Are number of toilet breaks and amount of beverage consumed related? How? Give the value of the statistic and the probability value.

b. Are toilet breaks and production related? How? Give the value of the statistic and the probability value.

c. If you were to wish to build a prediction equation based on the above information would you need to use both number of toilet breaks and amount of beverage consumption in the equation? Why/why not?

d. Build a prediction equation for production using SPSS and analyze the data. Share your analyzed results, including the R square value and probability.

8. An airport manager is interested in the relationship between job satisfaction and stress. Within his own airport, the manager asked a random sample of workers two questions. The first question asked how satisfied workers were with their job and had them rate their satisfaction on a scale from 1 to 50. The second question asked how stressful they found their job in a given week. Again the workers rated their stress level on a scale from 1 to 50.

Data Set

Q1: Satisfaction Q2: Stress

44 32

34 25

26 29

12 45

47 35

56 25

45 24

48 13

39 15

45 49

35 29

38 39

29 45

40 33

30 44

44 32

34 25

26 29

12 45

47 35

56 25

45 24

48 13

39 15

45 49

35 29

38 39

29 45

40 33

30 44

a. What is the null hypothesis?

b. What type of statistical test best assesses the relationship between job satisfaction and level of stress?

c. What are the results? Give the statistic and probability.

d. What will you do with the null hypothesis?

9. A professor wants to know whether there is a difference in the time it takes to complete the Graduate Capstone Project between students who take 605 before completing 15 graduate credit hours and students who take 605 after completing at least 15 credit hours.

Data Set

Time to complete GCP reported in terms

< 15 credit hours 15+ credits hours

2 1

2 1

3 1

1 1

1 1

1 1

2 1

2 1

2 1

2 1

3 2

4 1

2 1

2 1

2 1

2 1

2 1

2 1

2 2

2 1

a. What is the null hypothesis?

b. What type of statistical test best did you use?

c. What are the results? Are they significant? (Give the statistic and probability.)