statistics SAS asignment need asap
iamnickok
STAT 5132&6032 Homework 4 (Due: Monday 2/27/2017) Spring 2017
Attach to front of homework paper
Student name (LAST, First):
Reminder:
• DO NOT hand in unedited SAS output/code.
• ONLY include the results required
• Answer questions IN ORDER; Include question number; Label graphs
• Include SAS input for questions at the end of the entire homework as Appendix
• SAVE your SAS code, since you may be asked to continue problems on successive home- work
Reading: Montgomery Chapter 3
1. You want to compare 5 treatments using a one-way fixed effects model. You want enough replication so that the F test has at least 80% power (at the 5% significance level) when the largest difference between means is 4 units. Suppose that σ2 = 9. How large must n be (assuming balanced experiment, i.e., ni = n)? Make sure you show your software inputs or hand calculations to receive full credits.
2. Recall Exercise 5 in Lecture 9. There were a = 6 randomly chosen schools each with n = 5 teachers.
a. How much power does this study have if the true variances were such that 2σ2τ = σ2? Make sure you show your software inputs or hand calculations to receive full credits.
b. In a random effects situation you can either increase a and/or n to increase the power. You investigate different combinations and find the following:
• a = 11, n = 5, 81.6% power
• a = 9, n = 6, 82.2% power
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• a = 8, n = 7, 83.7% power
• a = 7, n = 8, 83.6% power
If it costs $20 in time and resources to evaluate each teacher once at a school and $100 in time and resources to access a school, which of these options would you choose? Explain your answer.
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