a. What is an unpaired t test?
b. Identify the two hypotheses involved in an unpaired t test.
c. What is the “independence” requirement? Give a concrete example.
d. How is an unpaired t test similar to and different from an ordinary t test for just one sample?
e. When is each standard error appropriate? (Answer both in words and using a formula.)
f. What new assumption is needed for the unpaired t test to be valid for small samples? What can you do if this assumption is grossly violated?