Question

A fourth-grade teacher suspects that the time he administers a test, and what sort of snack his students have before the test, affects their performance. To test his theory, he assigns 90 fourth-grade students to one of three groups One group gets candy (jelly beans) for their 9:55 AM snack. Another group gets a high-protein snack (cheese) for their 9:55 AM snack. The third group does not get a 9:55 AM snack. The teacher also randomly assigns 10 of the students in each snack group to take the test at three different times: 10:00 AM (right after snack), 11:00 AM (an hour after snack), and 12:00 PM (right before lunch). Suppose that the teacher uses a two-factor, independent-measures ANOVA to analyze these data. Without post hoc tests, which of the following questions can be answered by this analysis? Check all that apply. (Note: Assume that receiving no snack is considered one type of snack.) Do students who eat a protein snack score higher than students who have no snack? Does student performance on the test depend on the time of the test? Does the effect of the type of snack depend on the timing of the test? Does the effect of the timing of the test depend on the type of snack the students eat? U In the following table are the mean test scores for each of these nine different combinations of snack type and test timing. Factor B: Time of Test 10:00 AM 11:00 AM 12:00 PM Candy Snack M = 92,0 M - 340 M-88.0 M-88.0 Factor A: Type of Snack Protein Snack M 89.5 M 38.0 M 87.5 M 18.0 No Snack M-900 M910 M-83.0 M - 83.0

Answer 1

Answer:

Given that:

A fourth - grade teacher suspects that the time he administers a test ,and what sort of snack his students have before the test,affects their performance.

1)

Only option B) is correct

$\mu _{10.00AM}=\mu _{11.00AM}=\mu _{12.00PM}$

The assumptions are:

1) The population defines by the nine treatment conditions are normally distributed.

2) The test scores within each of the nine samples (one for each treatment condition)are independent.

3) The population defines by the nine treatment conditions have equal variance regardless of snack test time.