Question

In a study the physician wanted to test the hypothesis whether time to get pregnant is different when women switch to decaffeinated coffee from caffeinated coffee. So, she recruited four women who were regular coffee drinkers and who were planning on having several children. First she monitored the number of months it took these women to conceive when they were still drinking regular coffee; and then she monitored months to conception after these same women switched to decaff for their second pregnancy. (The data are in the following table.)

Month to conception while consuming .........

Caffeinated coffee

de-Caffeinated coffee

7

  4

9

10

11

5

3

3

Using   alpha=.­01, test the hypothesis whether caffeine consumption affects the number of months to conception by comparing "months to conception" between when drinking caffeinated coffee and when drinking de-caffeinated coffee using a Matched Paired Samples t-test.

1. State the Null and Alternative hypotheses.

2. State the Degrees of Freedom, and Critical value (at alpha= .01)

3. Compute an appropriate Standard Deviation

4. Compute an appropriate Standard Error of the Mean.

5. Compute the t-value and state your decision on the hypothesis testing.

Answer 1

Conclusion is that we can't reject the null hypothesis that caffeine consumption don't affect the number of months to conception.