Question 1

A random sample of 12 bags of barbecue potato chips is collected and the price of each determined. The mean was $1.03 with a standard deviation of 7 cent ($0.07). Using $\alpha$  = 0.10, we wish to test H0: $\mu$ = $1.00. The result is significant

Accepted Answer

A)  for both Ha: $\mu$> $1.00 and for Ha: $\mu$$\neq$ $1.00. 
B)  for Ha: $\mu$ > $1.00 but not for Ha: $\mu$$\neq$ $1.00. 
C)  for Ha: $\mu$ $\neq$$1.00 but not for Ha: $\mu$ > $1.00. 
D)  neither for Ha:$\mu$ > $1.00 nor for Ha: $\mu$ $\neq$ $1.00.

Question 2

Use the following information for questions:
 An airport official wants to assess if the flights from one airline (Airline 1) are less delayed than flights from another airline (Airline 2). Let $µ_1$ = average delay for Airline 1 and $µ_2$ = average delay for Airline 2. A random sample of 10 flights for Airline 1 shows an average of 9.5 minutes delay with a standard deviation of 3 minutes. A random sample of 10 flights for Airline 2 shows an average of 12.63 minutes delay with a standard deviation of 3 minutes. Assume delay times are normally distributed, but do not assume the population variances are equal. Use the conservative "by hand" estimate for the degrees of freedom.
-What is the p-value?

Accepted Answer

A)  p-value = 0.021 
B)  p-value = 0.022 
C)  p-value = 0.038 
D)  None of the above

Question 3

Use the following information for questions:
 A sample of passengers flying on small planes gave a mean total weight (passenger weight including shoes, clothes, and carry-on) of 200 pounds and a standard deviation of 60 pounds.
-What is the estimated effect size for comparing this result to the FDA guideline level of 185 pounds?

Accepted Answer

A)  0.25 
B)  -0.25 
C)  -15 
D)  15

Question 4

Suppose that a difference between two groups is examined. In the language of statistics, the alternative hypothesis is a statement that there is __________

Accepted Answer

A)  no difference between the sample means. 
B)  a difference between the sample means. 
C)  no difference between the population means. 
D)  a difference between the population means.

Question 5

Use the following information for questions:
 Cholesterol measurements for a sample of males following a new diet plan gave a mean of 208 and a standard deviation of 10.
-Based on Cohen's interpretation, this effect is

Accepted Answer

A)  a small effect, not obvious without statistics. 
B)  a medium effect, obvious to careful observers. 
C)  a large effect, obvious to most observers.

Question 6

Use the following information for questions:
In the survey of a random sample of students at a university, two questions were "How many hours per week do you usually study?" and "Have you smoked marijuana in the past six months?" An analysis of the results produced the following Minitab output: 
-What is the appropriate alternative hypothesis for this question?

Accepted Answer

A)  Ha: $µ_1$-$µ_2$ = 0 
B)  Ha: $\overline{x}_1$ - $\overline{x}_2$ a: $\overline{x}_1$- $\overline{x}_2$ $\neq$ 0 
D)  Ha: $µ_1$-$µ_2$ < 0

Exam 13: Testing Hypotheses About Means

A random sample of 12 bags of barbecue potato chips is collected and the price of each determined. The mean was $1.03 with a standard deviation of 7 cent ($0.07) . Using $\alpha$ = 0.10, we wish to test H₀: $\mu$ = $1.00. The result is significant

Suppose that a difference between two groups is examined. In the language of statistics, the alternative hypothesis is a statement that there is __________

Use the following information for questions: Cholesterol measurements for a sample of males following a new diet plan gave a mean of 208 and a standard deviation of 10. -Based on Cohen's interpretation, this effect is

Exam 13: Testing Hypotheses About Means

A random sample of 12 bags of barbecue potato chips is collected and the price of each determined. The mean was $1.03 with a standard deviation of 7 cent ($0.07) . Using α\alphaα = 0.10, we wish to test H0: μ\muμ = $1.00. The result is significant

Suppose that a difference between two groups is examined. In the language of statistics, the alternative hypothesis is a statement that there is __________

Use the following information for questions: Cholesterol measurements for a sample of males following a new diet plan gave a mean of 208 and a standard deviation of 10. -Based on Cohen's interpretation, this effect is

A random sample of 12 bags of barbecue potato chips is collected and the price of each determined. The mean was $1.03 with a standard deviation of 7 cent ($0.07) . Using $\alpha$ = 0.10, we wish to test H₀: $\mu$ = $1.00. The result is significant