Question

A professor of women's studies is interested in determining if stress affects the menstrual cycle. Ten women are randomly sampled for an experiment and randomly divided into two groups. One of the groups is subjected to high stress for two months while the other lives in a relatively stress-free environment. The professor measures the menstrual cycle (in days) of each woman during the second month. The following data are obtained. High stress Relatively stress free 18 19 25 26 20 23 22 30 26 31 The obtained value of the appropriate statistic for evaluating Ho is t-4.73 Ot-4.17 Ot--3.05 Ot 47 1pts Question 6 We can reject the null hypothesis if O t-obtained-t-critical O t-obtained > t-critical O t-obtained < t-critical o It-obtainedl It-criticall

Answer 1

NO sample 1 sample 2 mean std deviation 20.400 2.074 27.600 2.702 = 27.600 = - = 20.400X， 2.0745- 5.000n， 2.702 n = 5.000 Point estimate：X1-X2 = -7,200 std error of difference=Se= vis?,/n,+s?,/nz) 1.5232 test statt = (x-x-4)/se -4.727

from above test statistic t = -4.73

6)

we can reject null hypothesis: if |t-obtained| >=|t-critical|