A researcher is concerned that his new antihypertensive medication may be causing insomnia in some of his patients. Suppose he gathers a SRS of 65 patients treated with the study drug with a sample average of 6.6 hours of sleep and a =1.1. Assuming that insomnia can be quantified as an average of 4.5 hours of sleep, can we determine with 95% confidence that his drug avoids diagnosis of insomnia as a side-effect?

Ho: =4.5, Ha: <4.5

Z stat=12.4

Pvalue=<0.001

Fail to reject the Ho that the sleep received by the participants with the new study drug qualifies as potential insomnia at 95% confidence

Ho: =4.5, Ha: >4.5

Z stat=15.4

Pvalue=<0.0001

Reject the Ho that the sleep received by the participants with the new study drug qualifies as potential insomnia at 95% confidence

Ho: =4.5, Ha: >4.5

Z stat=20.1

Pvalue=<0.0001

Reject the Ho that the sleep received by the participants with the new study drug qualifies as potential insomnia at 95% confidence

Question 2

Suppose researchers are interested in estimating the prevalence of HIV in a population of adolescent intravenous drug users determined to equal 9.4% in the population. In order to estimate the prevalence of the disease, the researchers need to randomly sample from the population of potential participants in their study. Suppose the researchers are able to randomly sample 127 participants, and find that 29 are co-infected with the diseases of interest.

A)Can we approximate this distribution with the normal? Why or why not?

B)Create a Z score for this sample.

C)What is the probability of observing the sample that was collected?

A) No, npq<5

B) Z=7.124

C) Probability <0.001

A) No, npq<5

B) Z=7.124

C) Probability <0.001

A) Yes, npq>5

B) Z=5.188

C) Probability <0.0001

Question 3

A researcher is interested in the decrease in adolescent BMI after a new after school program is implemented to promote exercise in children. Suppose the researcher wants to collect a SRS of children from the program in order to evaluate their loss in BMI. If the population standard deviation is 4.87 kg/m², and the researcher wants to capture the mean BMI within 4 kg/m², how many children should he sample to attain 95% confidence?

5.69~6

7.88~8

4.75~5

Question 4

Which of the following best describes the correct interpretation of a pvalue resulting from a statistical test?

The probability of an event occurring given that the null hypothesis is true

The probability of an event occurring given that the alternative hypothesis is true

The likelihood that you will reject the alternative hypothesis

The likelihood that your sample calculation captures the true population statistic

Question 5

Suppose the following table summarizes the BMI for a population of 8 participants in a weight loss program.

Participant

BMI

A

32.6

B

31.7

C

26.8

D

29.3

E

25.4

F

33.2

G

29.4

H

26.9

A) Calculate and .

B) BMI over 30 is considered obese. Assume that this population follows a normal distribution. What proportion of women is obese?

C) BMI between (25, 29.9) is considered overweight. What proportion of this population is overweight?

A) =30.1, =1.8

B) 0.51

C) 0.46

A) =25.2, =3.1

B) 0.38

C) 0.44

A) =29.4, =2.7

B) 0.41

C) 0.52