Question

In: Statistics and Probability

A powder diet is tested on 49 people, and a liquid diet is tested on 36...

A powder diet is tested on 49 people, and a liquid diet is tested on 36 different people. Of interest is whether the liquid diet yields a higher mean weight loss than the powder diet. The powder diet group had a mean weight loss of 42 pounds with a standard deviation of 12 pounds. The liquid diet group had a mean weight loss of 45 pounds with a standard deviation of 14 pounds. Conduct a hypothesis test at the 5% level.

What is the test statistic?

Solutions

Expert Solution


The test hypothesis is

Now, the value of test static can be found out by following formula:

Degrees of freedom on the t-test statistic are n1 + n2 - 2 = 49 + 36 - 2 = 83
This implies that

Since, the t distribution is symmetric about zero, so -t_{0.05, 83}
Since, we fail to reject the null hypothesis H0 at


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