Statistics assignment help

DSCI 346-01 F16: Chapter 10 On-Paper Assignments 40 points

Begin each problem by re-writing the problem. Minitab is required; attach or include your output. Use Word; you may handwrite equations. You may want to refer to the Minitab handouts for Chapter 10 (on Canvas under Modules, Chapter 10 Handouts).

1. A cognitive retraining clinic assists outpatient victims of head injury, anoxia, or other conditions that

result in cognitive impairment. Each incoming patient is evaluated to establish an appropriate

treatment program and estimated length of stay. To see if the evaluation teams are consistent, 12

randomly chosen patients are separately evaluated by two expert teams (A and B) as shown. The data

file is named LengthStay. (15 points)

Estimated Length of Stay in Weeks

Patient

Team 1 2 3 4 5 6 7 8 9 10 11 12

A 24 24 52 30 40 30 18 30 18 40 24 12

B 24 20 52 36 36 36 24 36 16 52 24 16

a. At the .10 level of significance, is there a difference between the evaluator teams’ estimated length

of stay? State your hypotheses and show all 7 steps clearly.

b. Give and interpret the p-value.

c. What assumption is required for this test? Use an appropriate graph to check the assumption and

state your findings.

d. Verify with Minitab, but attaching or including the output.

2

2. Cash withdrawals from a college credit union for a random sample of 30 Fridays and 30 Mondays are

shown. At α = .01, is there a difference in the mean withdrawal on Monday and Friday? The data are

shown below and may be found in the data filed named ATM. 25 points

a. First test to determine if the variances in cash withdrawals differ between Friday and Monday.

Show and follow the 7 steps.

b. Verify your results in part (a) using Minitab.

c. Using the information from your results in part (a), test to determine if the average cash

withdrawals differ between Friday and Monday. Follow and show the 7 steps for hypothesis

testing.

d. Find the p-value and interpret it.

e. Verify your results in part (c) using Minitab.

Randomly Chosen Cash Withdrawals ($)

Friday Monday

250 10 10 40 30 10

20 10 30 100 70 370

110 20 10 20 20 10

40 20 40 30 50 30

70 10 10 200 20 40

20 20 400 20 30 20

10 20 10 10 20 100

50 20 10 30 40 20

100 20 20 50 10 20

20 60 70 60 10 20