## Business Statistic

Business Statistic

1.

Use the information below to answer the question.

The following table provides data on a sample of customers who visited a local restaurant. The restaurant owner believes that the average profit per customer exceeds $25.

36.73 35.50

25.92 38.36

41.65 25.50

18.78 19.78

33.14 22.22

20.85 26.23

22.13 32.33

28.46 34.15

34.72 24.21

24.20 28.95

21.84 19.74

20.75

Which of the following is the critical value using a level of significance of 0.05? (Points : 1)

1.717

-1.717

1.7139

-2.0739

Question 2.2. The null hypothesis ________. (Points : 1)

describes an existing theory or belief that is accepted as correct in the presence of contradictory data

describes an existing theory or belief that is accepted as correct in the absence of contradictory data

is based on new information provided by sample data

is based on new information provided by population data

Question 3.3. A Type I error occurs when ________. (Points : 1)

the null hypothesis is actually false, but the hypothesis test incorrectly fails to reject it

the null hypothesis is actually true, and the hypothesis test correctly fails to reject it

the null hypothesis is actually false, and the hypothesis test correctly reaches this conclusion

the null hypothesis is actually true, but the hypothesis test incorrectly rejects it

Question 4.4. The alternative hypothesis is denoted by ________. (Points : 1)

HN

H0

H1

HAl

Question 5.5. The probability of making a Type I error is generally denoted by ________. (Points : 1)

a

ß

?

µ

Question 6.6. The alternative hypothesis ________. (Points : 1)

describes an existing theory or belief that is accepted as correct in the absence of contradictory data.

is based on new information provided by population data.

is based on new information provided by sample data.

is not deemed to be an important part of inferential statistics.

Question 7.7.

Use the information below to answer the question.

The following table provides data on a sample of customers who visited a local restaurant. The restaurant owner believes that the average profit per customer exceeds $25.

36.73 35.50

25.92 38.36

41.65 25.50

18.78 19.78

33.14 22.22

20.85 26.23

22.13 32.33

28.46 34.15

34.72 24.21

24.20 28.95

21.84 19.74

20.75

Which of the following is the correct conclusion? (Points : 1)

The null hypothesis that the average profit per customer exceeds $25 cannot be rejected.

The null hypothesis that the average profit per customer does not exceed $25 is rejected.

The null hypothesis that the average profit per customer does not exceed $25 cannot be rejected.

The null hypothesis that the average profit per customer exceeds $25 is rejected.

Question 8.8. A helpful analogy of hypothesis testing might be the concept of ________. (Points : 1)

the U.S. legal system-innocent until proven guilty

better safe than sorry.

the theory of relativity

the central limit theorem

Question 9.9. In statistical terminology, educational level is an example of a ________. (Points : 1)

continuous variable

residual

factor

dependent variable

Question 10.10.

Use the below information to answer the question.

A company wishes to test whether the proportion of female managers is the same as the proportion of male managers. The following table provides data for a sample of employees.

Females Males

Number of managers 18 23

Sample size 45 75

Compute the 99% confidence interval estimate of the difference between the two proportions. [Hint: Use PHStat] (Points : 1)

(0.139, -0.326)

(0.084, -0.270)

(-0.084, 0.270)

(-0.139, 0.326)

Question 11.11.

Use the below information to answer the question.

A company wishes to test whether the proportion of female managers is the same as the proportion of male managers. The following table provides data for a sample of employees.

Females Males

Number of managers 18 23

Sample size 45 75

Which of the following is the conclusion? (Points : 1)

We reject H0 that the proportion of female managers is the same as the proportion of male managers.

We should not reject H0 that the proportion of female managers is not the same as the proportion of male managers.

We reject H0 that the proportion of female managers is not the same as the proportion of male managers.

We should not reject H0 that the proportion of female managers is the same as the proportion of male managers.

Question 12.12. Another term for p-value is ________. (Points : 1)

degrees of freedom

random effect

probability density function

observed significance level

Question 13.13. In most practical applications, the population standard deviation will not be known but it is estimated from the ________. (Points : 1)

population

sample

test statistic

t-distribution

Question 14.14.

Use the below information to answer the following question.

A company wishes to test whether the proportion of female managers is the same as the proportion of male managers. The following table provides data for a sample of employees.

Females Males

Number of managers 18 23

Sample size 45 75

Formulate the null and the alternative hypotheses to determine if the proportion of female managers is the same as the proportion of male managers. (Points : 1)

H0: pfemales – pmales ? 0

H1: pfemales – pmales = 0

H0: pfemales – pmales = 0

H1: pfemales – pmales > 0

H0: pfemales – pmales = 0

H1: pfemales – pmales ? 0

H0: pfemales – pmales = 0

H1: pfemales – pmales < 0

Question 15.15. To determine if there was a statistically significant difference in the means of two independent groups, which statistical tool would one be most likely to employ to assess the significance of any observed difference? (Points : 1)

paired samples t-test

chi-square test for independence

Levene’s test for homogeneity of variances

independent samples t-test

Question 16.16. Hypothesis testing involves drawing inferences about two contrasting ________ relating to the value of a population parameter. (Points : 1)

theorems

data sets

assumptions

propositions

Question 17.17.

Use the below information to answer the question.

A company wishes to test whether the proportion of female managers is the same as the proportion of male managers. The following table provides data for a sample of employees.

Females Males

Number of managers 18 23

Sample size 45 75

Which of the following is the test statistic? [Hint: Use PHStat] (Points : 1)

1.96

-1.04

-1.96

1.04

Question 18.18. The power of the test represents the ________. (Points : 1)

probability of correctly failing to reject the null hypothesis when it is indeed true

probability of incorrectly rejecting the null hypothesis when it is actually true

probability of incorrectly failing to reject the null hypothesis when it is actually false

probability of correctly rejecting the null hypothesis when it is indeed false

Question 19.19. The t-Test Statistic has a t distribution with ________ degrees of freedom. (Points : 1)

n

n + 1

n – 2

n – 1

Question 20.20. The power of the test has a value of ________. (Points : 1)

1 – a

1 + ß

1 – ß

a – ß