The document discusses using a z-test instead of a t-test when the population standard deviation is unknown. Using a z-test in this situation results in a true level of significance that is smaller than the nominal .01 level specified for the test.
Even though the population standard deviation is unknown, an investi.pdf
1. Even though the population standard deviation is unknown, an investigator uses z rather than the
more appropriate t to test a hypothesis at the .01 level of significance. In this situation the true
level of significance of this test is:
1. equal to .01
2. smaller than .01
3. larger than .01
4. unknown
Solution
2. smaller than .01