# Biological Data Analysis: Homework 7

## Due Tuesday, Nov. 1

**You must type this and all other homework assignments. Do not e-mail the assignment to me; turn it in early (at 322 Wolf) for a foreseeable absence, or turn it in late after an unexpected absence from class. **

**1. **You are planning a large study of one-legged eyes-shut balance time, one that will have multiple observers measuring balance time for multipe subjects per observer. You want to know whether there is a significant amount of variation among observers in the balance times of their subjects. You also want to know whether female and male observers differ significantly in the mean balance time of their subjects. I have created a manageable-sized subset of the balance time data set and have added a column for the sex of the observer. Log-transform the balance times, then perform a nested anova. Present the test statistics, degrees of freedom, P-values, and percent of variation explained.

**2. **Based on your results from question 1, what conclusions do you draw? How would the results affect how you design your large study of balance times?

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This page was last revised October 25, 2016. Its URL is
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