Question

The two-sample t-test is one of the most commonly used hypothesis tests in Six Sigma work. It is applied to compare whether the average difference between two groups is really significant or if it is due instead to random chance. Select an application of the two-sample t-test and describe how it was justified to use the t-test for this particular application. Describe what the P-value of the 2-sample t-test of your example in part (1) means. Note that you are not being asked to provide a general definition of the P-value in hypothesis testing problems. You are being asked to interpret the P-value in the context of the particular example that you have selected.

Answer 1

A2 sample t test can be used when we think that variances of both population 1 and population 2 are about the same and can be said to be similar

An application of the 2 sample t test is comparing 2 machines of the same unit

one machine can be new relative to the other but both are doing the same task

To test if the new machine is actually doing the task faster than the old machine we can use a 2 sample t test

At a said level of significance we can check the null hypothesis and alternate hypothesis and confirm if we need to reject the null or not