Question 1

Consider the following to answer the question(s) below:
An Internet service provider is interested in testing to see if there is a difference in the mean weekly connect time for users who come into the service through a dial-up line, DSL, or cable Internet. To test this, the ISP has selected random samples from each category of users and recorded the connect time during a week period. The following is partial Excel output for the data. 
-The P-value for this statistic is < 0.001. Therefore, at α = 0.05

Accepted Answer

A)  we reject the null hypothesis and conclude that at least two of the mean weekly connect times are different. 
B)  we fail to reject the null hypothesis. 
C)  we know average connect times are the same for all connection methods. 
D)  we reject the alternative hypothesis and conclude that the average weekly connect times are the same for all three methods of connection. 
E)  we support the null hypothesis and conclude that the method of connection is not significant.

Question 2

Consider the following to answer the question(s):
An advocacy group is interested in determining if gender (1 = Female, 2 = Male) affects executive level salaries. They take a random sample of executives in three different industries: (1 = Consumer Goods, 2 = Financial, 3 = Health Care). Salary data are collected. The two-way ANOVA results appear below. 
-Which of the following statements is true?

Accepted Answer

A)  This is an experiment. 
B)  This is an observational study. 
C)  This is a randomized block design. 
D)  This is an experimental study involving a randomized block design. 
E)  This is a completely randomized design.

Question 3

A survey of online consumers asked respondents to indicate how much money they spent for online purchases during the most recent Christmas holiday season. These data were analyzed to see if gender (1= Female; 2 = Male) and income level (1 = Low, 2 = Middle, 3 = High) influence the amount consumers spend online for holiday shopping. The two-way ANOVA results appear below.   a. Is this an experiment or observational study?
b. Are the conditions for two-way ANOVA met?
c. If so, perform the hypothesis tests and state your conclusions in terms of amount spent online, gender and income level.
d. Is it appropriate to interpret the main effects in this case separately? Explain.

Accepted Answer

The answer of A survey of online consumers asked respondents...

Question 4

Consider the following to answer the question(s) below:
Management styles differ among organizations and may potentially affect employee job satisfaction. A sample of employees was randomly selected from each of three companies with different management styles (Authoritarian, Laissez-faire and Participative) and asked to rate their level of job satisfaction on a 10-point scale (10 being the highest level of satisfaction). The data collected and partial ANOVA results appear below.
  
-The P-value for this statistic turns out to be < 0.001. Therefore, at α = 0.05

Accepted Answer

A)  we fail to reject the null hypothesis. 
B)  we reject the null hypothesis and conclude that at least two mean employee job satisfaction ratings are different. 
C)  we conclude that mean employee job satisfaction ratings are all equal across companies with different management styles. 
D)  we support the null hypothesis and conclude that management style does not affect employee job satisfaction rating. 
E)  we reject the alternative hypothesis and conclude that mean employee job satisfaction ratings are all equal across companies with different management styles.

Exam 15: Design of Experiments and Analysis of Variance Anova