Exam 12: Analysis of Variance

A manufacturer of automobile transmissions uses two different processes. Management ordered a study of the production costs to see if there is a difference between the two processes. A summary of the findings is shown next. What is the critical value of F at the 5% level of significance?

A large department store examined a sample of 18 credit card sales and recorded the amounts charged for each of three types of credit cards: MasterCard,Visa,and Discover. Six MasterCard sales,seven Visa,and five Discover sales were recorded. The store used an ANOVA to test if the mean sales for each credit card were equal. What are the degrees of freedom for the F-statistic?

In an ANOVA problem involving three treatments and 12 observations per treatment,SSE = 297. The MSE for this scenario is ________.

To employ Analysis of Variance (ANOVA),the populations being studied must be approximately normally distributed.

Given the following ANOVA table for three treatments each with six observations: What is the computed value of F?

A manufacturer of automobile transmissions uses three different processes. Management ordered a study of the production costs to see if there is a difference among the three processes. A summary of the findings is shown next. In an ANOVA table,what are the total degrees of freedom?

The following partial ANOVA table was derived from data having four treatments and a total of 16 observations. The mean square between treatments (MST)is ________.

Given the following ANOVA table for three treatments each with six observations: What is the critical value of F at the 5% level of significance?

In ANOVA,the null hypothesis is ________.

If the computed value of F is 0.99 and the F critical value is 3.89,we would not reject the null hypothesis.

When a blocking effect is included in an ANOVA,the analysis is more likely to detect differences in the treatment means.

The annual dividend rates for a random sample of 16 companies in three different industries,utilities,banking,and insurance,were recorded. The ANOVA comparing the mean annual dividend rate among three industries rejected the null hypothesis that the dividend rates were equal. The mean square error (MSE)was 3.36. The following table summarized the results: When comparing the mean annual dividend rate for companies in the utilities and insurance industries,which of the following 95% confidence intervals can be constructed?

Suppose an automobile manufacturer designed a radically new lightweight engine and wants to recommend the grade of gasoline that will have the best fuel economy. The four grades are regular,economy,premium,and super premium. The test car made three trial runs on the test track using each of the four grades. The miles per gallon were recorded for each grade. At the 0.05 level,what is the critical value of F used to test the hypothesis that the miles per gallon for each fuel are the same?

The college of business was interested in comparing the attendance for three different class times for a business statistics class. The data follow. What are the block and treatment degrees of freedom?

Suppose a package delivery company purchased 14 trucks at the same time. Five trucks were purchased from manufacturer A,four from manufacturer B,and five from manufacturer C. The cost of maintaining each truck was recorded. The company used ANOVA to test if the mean maintenance costs of the trucks from each manufacturer were equal. To apply the F-test,how many degrees of freedom must be in the denominator?

In ANOVA analyses,when the null hypothesis is rejected,we can test for differences between treatment means by ________.

In a two-way ANOVA with interaction,a significant interaction term indicates that ________.

In a two-way ANOVA with interaction,there are two factor effects and an interaction effect.

A two-way ANOVA with interaction has how many sources of variation?

An experiment to determine the most effective way to teach safety principles applied four different teaching methods. Some employees were given programmed instruction booklets and worked through the course at their own pace. Other employees attended lectures. A third group watched a television presentation,and a fourth group was divided into small discussion groups. A high of 10 was possible. A sample of five tests was selected from each group. The test grade results were: At the 0.01 level,what is the critical value?