Exam 16: Hierarchical and Randomized Block Analysis of Variance Models

To study the effects of diet plans on blood pressure, the researcher assigned 10 subjects to diet plan A, and 10 participants to diet plan B. Within each group, five of the subjects are male and five participants are female. Which of the following statement is true?

To study the effects of a new mathematics textbook, 30 students are randomly selected. Based on the scores of their achievement test, students are grouped into three groups (limited: 0-15, proficient: 16-30, advanced: 31-45). Half of the students in each group are then randomly assigned to use the new textbook, while the rest of the students continue to use the old textbook. Which of the following methods of blocking is employed here?

In the scenario as described in Question 10, suppose the instructors from the same department are randomly assigned to use either the lecture-based method or the computer-based method. The researcher is primarily interested in the effects of different instructional methods on student outcomes. Which of the following statements is correct?

Azita wants to evaluate the effects of three new types of word processors (1: MacrosoftWork; 2: ToogleDoc, 3: WordTerrific) on the employees' working efficiency. 12 employees were randomly selected and grouped into four blocks based on the amount of their daily tasks (higher values indicate heavier work load). Within each block, each employee was randomly assigned to use one of the three word processors. Their working efficiency as measured by the number of files processed per day is listed in the table. Conduct a two-factor randomized block ANOVA ( $\alpha$ = .05) and Bonferroni MCPs using SPSS to determine the results of the study. Subject Word Processor Workload Number of files processed 1 1 1 8 2 1 2 13 3 1 3 18 4 1 4 26 5 2 1 3 6 2 2 10 7 2 3 13 8 2 4 20 9 3 1 5 10 3 2 12 11 3 3 14 12 3 4 20

Compared to the two-factor fully-crossed ANOVA, the two-factor hierarchical ANOVA

If the correlation between the concomitant variable and dependent variable is .5, and the concomitant variable is measured on an ordinal scale, which of the following designs is recommended?

How many hypotheses are tested in a design denoted by A(B)?

An experiment was conducted to compare the effect of three types of daily schedules on the employees' work performance. The schedules all contained the same amount of tasks, but the tasks were listed in different orders in each schedule. The day of the week was used as the blocking variable. The mean scores on the dependent variable, the percentage of tasks completed, are listed here for each cell. Weekday Type of schedule Monday Tuesday Wednesday Thursday Friday 1 70 89 74 85 75 2 74 94 81 90 80 3 80 98 85 96 84 Use these cell means to graph the interaction between type of schedule and the day of the week. a. Is there an interaction between type of schedule and the day of the week? b. What kind of recommendation would you make to the manager?

If a design is denoted by A(BC), and there are four observations in each cell, which of the following effects can be studied?

based on the following figure. Each cell represents one combination of factor levels. The actual experiment assigns participants only to the combinations represented by the shaded cells. It is unknown whether the levels of the factors are fixed or randomly selected. -A is a random-effects factor and B is a fixed-effects factor. Each cell has 5 observations. The F_B ratio has degrees of freedom equal to?