Question

It is believed that students who begin studying for final exams a week before the test score differently than students who wait until the night before. Suppose you want to test the hypothesis that students who study one week before score greater than students who study the night before. A hypothesis test for two independent samples is run based on your data and a p-value is calculated to be 0.0053. What is the appropriate conclusion?

Question 9 options:

1)	The average score of students who study one week before a test is significantly different from the average score of students who wait to study until the night before a test.

2)	The average score of students who study one week before a test is significantly less than the average score of students who wait to study until the night before a test.

3)	The average score of students who study one week before a test is less than or equal to the average score of students who wait to study until the night before a test.

4)	We did not find enough evidence to say the average score of students who study one week before a test is greater than the average score of students who wait to study until the night before a test.

5)	The average score of students who study one week before a test is significantly greater than the average score of students who wait to study until the night before a test.

You are looking for a way to incentivize the sales reps that you are in charge of. You design an incentive plan as a way to help increase in their sales. To evaluate this innovative plan, you take a random sample of your reps, and their weekly incomes before and after the plan were recorded. You calculate the difference in income as (after incentive plan - before incentive plan). You want to test whether income after the incentive plan is less than income before the incentive plan. What are the hypotheses for this test?

Question 10 options:

1)	HO: μD = 0 HA: μD ≠ 0

2)	HO: μD > 0 HA: μD ≤ 0

3)	HO: μD ≥ 0 HA: μD < 0

4)	HO: μD ≤ 0 HA: μD > 0

5)	HO: μD < 0 HA: μD ≥ 0

A comparison between a major sporting goods chain and a specialty runners' store was done to find who had lower prices on running shoes. A sample of 37 different shoes was priced (in dollars) at both stores. To test whether the average difference is less than zero, the hypotheses are as follows: Null Hypothesis: μ_D ≥ 0, Alternative Hypothesis: μ_D < 0. If the average difference between the two stores (specialty - chain) is 1.71 with a standard deviation of 6.39, what is the test statistic and p-value?

Question 11 options:

1)	Test Statistic: 1.628, P-Value: 0.056

2)	Test Statistic: 1.628, P-Value: 0.944

3)	Test Statistic: -1.628, P-Value: 0.944

4)	Test Statistic: -1.628, P-Value: 0.056

5)	Test Statistic: 1.628, P-Value: 1.888

Answer 1

1)

since the test is two tailed: correct option is:

1)The average score of students who study one week before a test is significantly different from the average score of students who wait to study until the night before a test.

2)

3) H_O: μ_D ≥ 0
H_A: μ_D < 0    (since we are checking if μ_D is less than previous)

3)

sample mean 'x̄=	1.710
sample size   n=	37.00
sample std deviation s=	6.39
std error 'sx=s/√n=	1.0505
test stat t ='(x-μ)*√n/sx=	1.628
p value      =	0.056

option 4 is correct