Question:

A researcher wants to test whether production errors differ by time of day (Day, Evening, and Nigh shift). She randomly assigns a group of accountants to each of three different shifts and measures the number of errors they make per month. She obtains the following results:

Test for a difference at ? = .05

Day

?X = 11

?2 =23

n = 6

Evening

?X=27

?2=163

n = 6

Night

?X=36?

?2=273

n = 6

STEP 1: State the null and alternative hypotheses. (2 points)

STEP 2: Set up the criteria for making a decision. That is, find the critical value.(1 point)

STEP 3: Compute the appropriate test-statistic. Show your work! (12 points)

(I have computed SStot for you)

Rows: Source Between Within Total

Columns: SS df MS F

SS of within: 101.3

STEP 4: Evaluate the null hypothesis (based on your answers to the above steps).(1 point)

STEP 5: Based on your evaluation of the null hypothesis, what is your conclusion?(1point)

A. Based on your decision about the null in the previous problem, is it appropriate to conduct a post-hoc test? (1 point)

B. Calculate the magnitude of effect for the pQuestion:

A researcher wants to test whether production errors differ by time of day (Day, Evening, and Nigh shift). She randomly assigns a group of accountants to each of three different shifts and measures the number of errors they make per month. She obtains the following results:

Test for a difference at ? = .05

Day

?X = 11

?2 =23

n = 6

Evening

?X=27

?2=163

n = 6

Night

?X=36?

?2=273

n = 6

STEP 1: State the null and alternative hypotheses. (2 points)

STEP 2: Set up the criteria for making a decision. That is, find the critical value.(1 point)

STEP 3: Compute the appropriate test-statistic. Show your work! (12 points)

(I have computed SStot for you)

Rows: Source Between Within Total

Columns: SS df MS F

SS of within: 101.3

STEP 4: Evaluate the null hypothesis (based on your answers to the above steps).(1 point)

STEP 5: Based on your evaluation of the null hypothesis, what is your conclusion?(1point)

A. Based on your decision about the null in the previous problem, is it appropriate to conduct a post-hoc test? (1 point)

B. Calculate the magnitude of effect for the previous problem and interpret what it means. (2 points)revious problem and interpret what it means. (2 points)

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