5: Two Sample Test of Hypothesis

Question 1

What are the assumptions necessary for calculating a probability with two sample-test of means?

1. ___
2. ___
3. ___

Answer 1

1. The two populations follow normal distributions.
2. The two samples are unrelated, that is, independent.
3. The standard deviations for both populations are known.

Question 2

Recall the 6-Step Procedure for Testing a Hypothesis:

1. ___
2. ___
3. ___
4. ___
5. ___
6. ___

Answer 2

Step 1: State the Null Hypothesis (H0) and the Alternate Hypothesis (H1)2.
Step 2: Select a Level of Significance
Step 3: Select the Test Statistic
Step 4: Formulate the Decision Rule
Step 5: Make a Decision
Step 6: Interpret the Result

Question 3

Characteristics of the two sample tests:

1. ___
2. ___

Answer 3

1. We assume the sampled populations have equal but unknown standard deviations.
2. Because of this assumption, we combine or “pool” the sample standard deviations.
   We use the t distribution as the test statistic.

Question 4

There are two types of dependent samples:

1. ___
2. ___

Answer 4

1. Those characterized by a measurement, an intervention of some type, and then another measurement
2. A matching or pairing of the observations.