Question

You wish to test the following claim (HaHa) at a significance level of α=0.001α=0.001.

      Ho:μ1=μ2Ho:μ1=μ2
      Ha:μ1<μ2Ha:μ1<μ2

You believe both populations are normally distributed, but you do not know the standard deviations for either. However, you also have no reason to believe the variances of the two populations are not equal. You obtain the following two samples of data.

Sample #1	Sample #2
71.1 63.8 81 49.3 62.8 59.3 43.7 53.6 57.4 46.8 54.6 46.8 60.5 86.5 81 53.6 55.8 83.2 66.1	78.4 83.1 70.3 80.2 74.5 65.1 62.6 79.9 66.2 67.2 59.5 66.5 85.7 60.8 76.2 56.7 75.1 60.8 70.7 56.7 65.1 71.7

What test would you use?

• T-Test (Matched Pairs)
• 2-SampTTest (pooled)
• 2-PropZInterval
• 2-SampTTest (not pooled)
• 2-PropZTest
• 2-SampTInterval

Answer 1

Solution :

Given that ,

sample size of both samples < 30

The variances of the two populations are not equal so we use 2-SampTTest (not pooled) .