Exam 12: Analysis of Variance

Recently,a department store chain was interested in determining if there was a difference in the mean number of customers who enter the three stores in Seattle.The analysts set up a study in which the number of people entering the stores was counted depending on whether the day of the week was Saturday,Sunday,or a weekday.The following data were collected: Given this format,which of the following is true?

Applebee's International,Inc. ,is a U.S.company that develops,franchises,and operates the Applebee's Neighborhood Grill and Bar restaurant chain.It is the largest chain of casual dining restaurants in the country,with over 1,500 restaurants across the United States.The headquarters is located in Overland Park,Kansas.The company is interested in determining if mean weekly revenue differs among three restaurants in a particular city.The file entitled Applebees contains revenue data for a sample of weeks for each of the three locations. Test to determine if blocking the week on which the testing was done was necessary.Use a significance level of 0.05.

A chain of fast food restaurants wants to compare the average service times at four different restaurants.They want to conduct a hypothesis test to determine if all four means are the same or not.If n = 10 observations are taken at each of the four restaurants,then the degrees of freedom are D₁ = 39 and D₂ = 3.

Examine the following two-factor analysis of variance table: Complete the analysis of variance table.

Applebee's International,Inc. ,is a U.S.company that develops,franchises,and operates the Applebee's Neighborhood Grill and Bar restaurant chain.It is the largest chain of casual dining restaurants in the country,with over 1,500 restaurants across the United States.The headquarters is located in Overland Park,Kansas.The company is interested in determining if mean weekly revenue differs among three restaurants in a particular city.The file entitled Applebees contains revenue data for a sample of weeks for each of the three locations. Based on the data gathered by Applebee's,can it be concluded that there is a difference in the average revenue among the three restaurants?

A study was recently conducted to see whether the mean starting salaries for graduates of engineering,business,healthcare,and computer information systems majors differ.A random sample of 8 graduates was selected from each major.The following shows the results of the ANOVA computations.However,the degrees of freedom column has been omitted.The correct number of degrees of freedom for the within variation is 28. ANOVA: Single Factor

A test is conducted to compare three different income tax software packages to determine whether there is any difference in the average time it takes to prepare income tax returns using the three different software packages.Ten different person's income tax returns are done by each of the three software packages and the time is recorded for each.Assuming that results show that blocking was effective,this means that:

In a recent one-way ANOVA test,SSW was equal to 15,900 and the SSB was equal to 3,100.Therefore,SST is equal to 12,800.

Applebee's International,Inc. ,is a U.S.company that develops,franchises,and operates the Applebee's Neighborhood Grill and Bar restaurant chain.It is the largest chain of casual dining restaurants in the country,with over 1,500 restaurants across the United States.The headquarters is located in Overland Park,Kansas.The company is interested in determining if mean weekly revenue differs among three restaurants in a particular city.The file entitled Applebees contains revenue data for a sample of weeks for each of the three locations. If you did conclude that there was a difference in the average revenue,use Fisher's LSD approach to determine which restaurant has the lowest mean sales.

The Tukey-Kramer method for multiple comparison is used after the analysis of variance F-test has lead us to reject the null hypothesis that all population means are equal.

Respond to the following questions using this partially completed one-way ANOVA table: How many different populations are being considered in this analysis?

Examine the following two-factor analysis of variance table: Determine if interaction exists between factor A and factor B.Use alpha = 0.05.

Respond to the following questions using this partially completed one-way ANOVA table: How many different populations are being considered in this analysis?

In a one-way analysis of variance design,there is a single factor of interest but there may be multiple levels of the factor.

Which of the following is the minimum number of required replications per cell for a two-factor ANOVA design if you plan to test for interactive effects between factors A and B?

A study was conducted to determine if differences in new textbook prices exist between on-campus bookstores,off-campus bookstores,and Internet bookstores.To control for differences in textbook prices that might exist across disciplines,the study randomly selected 12 textbooks and recorded the price of each of the 12 books at each of the three retailers.You may assume normality and equal-variance assumptions have been met.The partially completed ANOVA table based on the study's findings is shown here: Based on the study's findings,can it be concluded that there is a difference in the average price of textbooks across the three retail outlets? Conduct the appropriate hypothesis test at the alpha = 0.10 level of significance.

Assume you are conducting a two-way ANOVA and have found a significant interaction between the two factors.Explain what conclusions you can make from the results and what if any further steps should be taken.

Consider the following: How many blocks were used in this study?

A company has established an experiment with its production process in which three temperature settings are used and five elapsed times are used for each setting.The company then produces one product under each and measures the resulting strength of the product.The managers are mainly interested in determining whether the mean strength is the same at all temperature settings,but they know that controlling for process time is important.The following data were observed from the experiment: Based on these data and experimental design,the primary null hypothesis to be tested is H₀ : μ₁ = μ₂ = μ₃.

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 user and recorded the connect time during a week period.The following data were collected: Based upon these data and a significance level of 0.05,which of the following statements is true?