In: Statistics and Probability
A researcher wants to assess if there is a difference in the average age of onset of a certain disease for men and women who get the disease. Let = average age of onset for women and = average age of onset for men. A random sample of n1 = 30 women with the disease showed an average age of onset of = 83 years, with a sample standard deviation of s1 = 11.5 years. A random sample of n2 = 20 men with the disease showed an average age of onset of = 77 years, with a sample standard deviation of s2 = 4.5 years. Assume that ages at onset of this disease are normally distributed for each gender.
Conduct a hypothesis test to determine if the average age of onset of disease for women is greater than the average age of onset of disease for men. Test using a = 0.05 level of significance. Do this test by hand. Use the back if needed.
Step 2: Hypotheses
Step 3: Test Statistic
Step 4: P-value and Conclusion. Note: df = 41.
Post hoc analysis: Calculate a 95% confidence interval for the difference in average age of onset of disease for women vs men. Note: df = 41. Do this CI by hand. Use the back if needed.