Consumers can purchase nonprescription medications at food stores, mass merchandise stores such as

Target and Wal-Mart, or pharmacies. About 45% of consumers make such purchases at pharmacies.

What accounts for the popularity of pharmacies, which often charge higher prices?

A study examined consumers’ perceptions of overall performance of the three types of stores, using a

long questionnaire that asked about such things as “neat and attractive store,” “knowledgeable staff,”

and “assistance in choosing among various types of nonprescription medication.” A performance score

was based on 27 such questions. The subjects were 194 people chosen at random from the Indianapolis

telephone directory. Here are the means and standard deviations of the performance scores for the

sample.

Store type x s

*Professional Custom Writing Services from the Experts!*

Food stores 18.68 25.04

Mass merchandisers 32.11 33.21

Pharmacies 48.55 35.68

We do not know the population standard deviations, but a sample standard deviation s from so large a

sample is usually close to σ. Use s in place of the unknown σ in this exercise.

(a) What population do you think the authors of the study want to draw conclusions about?

sick people

citizens of Indianapolis

pharmacies

the American public

consumers

What population are you certain they can draw conclusions about?

citizens of Indianapolis

pharmacies

cons

9/16/2018 Topic Four Quiz

https://www.webassign.net/web/Student/Assignment-Responses/last?dep=19516880 3/7

Mass merchandisers

Pharmacies

(c) Based on these confidence intervals, are you convinced that consumers think that pharmacies

offer higher performance than the other types of stores? (In Chapter 12, we will study a

statistical method for comparing means of several groups.)

Yes, the pharmacy interval is well above the others.

Yes, the mass merchandiser interval is well above the others.

Yes, the food store interval is well below the others.

No, there is no clear evidence of a significant difference.

,

,

9/16/2018 Topic Four Quiz

https://www.webassign.net/web/Student/Assignment-Responses/last?dep=19516880 4/7

2. –/10 pointsMIntroStat9 7.E.034.

Since previous studies have reported that elite athletes are often deficient in their nutritional intake (for

example, total calories, carbohydrates, protein), a group of researchers decided to evaluate Canadian

high-performance athletes. A total of from eight Canadian sports centers participated

in the study. One reported finding was that the average caloric intake among the was

2403.7 kilocalories per day (kcal/d). The recommended amount is 2811.5 kcal/d.

For one part of the study, athletes from eight Canadian sports centers were surveyed.

Their average caloric intake was 3077.0 kilocalories per day (kcal/d) with a standard deviation of 986.0.

The recommended amount is 3422.2. Is there evidence that Canadian high-performance male athletes

are deficient in their caloric intake?

(a) State the appropriate

State the appropriate

(b) Carry out the test. (Round your answer for t to three decimal places.)

Give the degrees of freedom.

Give the P-value. (Round your answer to four decimal places.)

State your conclusion.

We have sufficient evidence to conclude that Canadian high-performance male athletes

are deficient in their calorie intake.

We do not have sufficient evidence to conclude that Canadian high-performance male

athletes are deficient in their calorie intake.

n = 324 athletes

n = 201 women

n = 114 male

H0.

H0: μ > 3422.2

H0: μ ≤ 3422.2

H0: μ ≥ 3422.2

H0: μ = 3422.2

H0: μ ≠ 3422.2

Ha.

Ha: μ ≥ 3422.2

Ha: μ = 3422.2

Ha: μ > 3422.2

Ha: μ ≠ 3422.2

Ha: μ < 3422.2

t =

9/16/2018 Topic Four Quiz

https://www.webassign.net/web/Student/Assignment-Responses/last?dep=19516880 5/7

(c) Construct a 95% confidence interval for the daily average deficiency in caloric intake. (Round

your answers to one decimal place.)

, kcal/day

9/16/2018 Topic Four Quiz

https://www.webassign.net/web/Student/Assignment-Responses/last?dep=19516880 6/7

3. –/10 pointsMIntroStat9 7.E.063.

Why do we naturally tend to trust some strangers more than others? One group of researchers decided

to study the relationship between eye color and trustworthiness. In their experiment the researchers

took photographs of 80 students (20 males with brown eyes, 20 males with blue eyes, 20 females with

brown eyes, and 20 females with blue eyes), each seated in front of a white background looking directly

at the camera with a neutral expression. These photos were cropped so the eyes were horizontal and at

the same height in the photo and so the neckline was visible. They then recruited 105 participants to

judge the trustworthiness of each student photo. This was done using a 10-point scale, where 1 meant

very untrustworthy and 10 very trustworthy. The 80 scores from each participant were then converted to

z-scores, and the average z-score of each photo (across all 105 participants) was used for the analysis.

Here is a summary of the results.

Eye color

Brown 40 0.55 1.68

Blue 40 −0.38 1.54

Can we conclude from these data that brown-eyed students appear more trustworthy compared to their

blue-eyed counterparts? Test the hypothesis that the average scores for the two groups are the same.

State the null and alternative hypotheses.

Report the test statistic, the degrees of freedom, and the P-value. (Round your test statistic to three

decimal places, your degrees of freedom to the nearest whole number, and your P-value to four decimal

places.)

t =

df =

P-value =

State your conclusion. (Use

We reject H0 and conclude that brown-eyed people seem more trustworthy according to this

experiment.

n x s

H0: μBrown ≠ μBlue

Ha: μBrown > μBlue

H0: μBrown = μBlue

Ha: μBrown > μBlue

H0: μBrown = μBlue

Ha: μBrown < μBlue

H0: μBrown = μBlue

Ha: μBrown ≠ μBlue

H0: μBrown ≠ μBlue

Ha: μBrown < μBlue

α = 0.05.)

9/16/2018 Topic Four Quiz

https://www.webassign.net/web/Student/Assignment-Responses/last?dep=19516880 7/7

We do not reject H0 and can not conclude that brown-eyed people seem more trustworthy

according to this experiment.