Exam 12: Analysis of Variance

The minimum and maximum of values of an F statistic are _______ and ______.

A random sample of 20 female executives from companies with assets over $1 million was selected and asked for their annual income and level of education. The ANOVA comparing the average income among three levels of education rejected the null hypothesis. The mean square error (MSE) was 250. The following table summarized the results: To compare the mean annual incomes of female executives with an undergraduate degree and female executives with a high school or less education, compute the 95% confidence interval.

All values in an F distribution must be _____________.

The college of business was interested in comparing the interaction of academic status and class time on class attendance. Three different classes were sampled for each cell in the table. The means for each cell follow. What are the interaction degrees of freedom?

An electronics company wants to compare the quality of their cell phones to the cell phones from three competitors. They sample 10 phones from each company and count the number of defects for each phone. If ANOVA was used to compare the average number of defects, then the treatments would be defined as:

When testing a hypothesis regarding the equality of two population means, what is the analogy to a blocking variable?

A bottle cap manufacturer with four machines and six operators wants to see if variation in production is due to the machines and/or the operators. The ANOVA table follows. What is the mean square for error?

A bottle cap manufacturer with four machines and six operators wants to see if variation in production is due to the machines and/or the operators. The ANOVA table follows. What are the degrees of freedom for the errors?

A bottle cap manufacturer with four machines and six operators wants to see if variation in production is due to the machines and/or the operators. The ANOVA table follows. What is the mean square for machines?

The college of business was interested in comparing the interaction of academic status and class time on class attendance. Three different classes were sampled for each cell in the table. The means for each cell follow. What are the error degrees of freedom?

What is the purpose of using a blocking variable in a two-way ANOVA?

A preliminary study of hourly wages paid to unskilled employees in three metropolitan areas was conducted. Seven employees were included from Area A, 9 from Area B, and 12 from Area C. The test statistic was computed to be 4.91. What can we conclude at the 0.05 level?

In a two-way ANOVA table with interaction, the error degrees of freedom is represented by the equation ________.

When testing for differences between treatment means, a confidence interval is computed with __________________.

What is the advantage of using ANOVA to test for differences among treatment means rather than testing all possible pairs of treatment means?

The college of business was interested in comparing the attendance for three different class times for a business statistics class. The data follow. What is the blocking variable?

One characteristic of the F distribution is that the computed F can only range between -1 and +1.

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

The number of mean square errors summarized in a two-way ANOVA table is _______. They are called _______.

In a study of protein breakfast bars, five bars from each of three brands were tested to see if the mean amount of protein per bar differs among the brands. If the brand sum of squares is 0.07 and the error sum of squares is 0.09, the calculated value of F is _____.