# Biological Data Analysis: Homework 5

## Due Tuesday, Oct. 6

**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. **If I wrote on your homework 4 that you needed to find a new data set, show me the new data set. Calculate the means for each group and list them; you don't have to do the other descriptive statistics (standard deviation, etc.).

**2. **Look at the data you collected for homework 4 (or your new data set) and pick out the two groups whose means are closest to each other. Do a two-sample t-test on the two groups you picked, using the Excel function described on the t-test page. Report the P-value and say what it means.

**3. **Do a two-sample t-test on the two groups in your data set with means that are the furthest apart. Report the P-value and say what it means.

**4. **Read the page in the textbook about SAS, then try to do a t-test on the two groups you picked in question 2, using SAS. Show your SAS program, your log file, and your output. If you can't get SAS to work, don't stay up all night struggling; show me your log file, or if you don't get that far, tell me what you're typing into the computer and what error message you're getting.

**5. **Study for the exam, then try to answer the study questions without looking at your notes. You don't need to turn in anything for this question.

Return to the
Biological Data Analysis syllabus

Return to John McDonald's home page

This page was last revised September October 2, 2015. Its URL is
http://udel.edu/~mcdonald/stathw5.html