Medicine and Clinical Studies
Over time, certain metabolic changes can cause the lens of the eye to become opaque, which leads to loss of vision. In this case, many adults elect to have cataract surgery in which the natural lens of the eye is removed and an artificial lens implant is inserted. A random sample of cataract surgeries was obtained and the length of each surgery was recorded (in hours).42 Past records indicate that the mean time for this type of surgery is 0.75 hour. Assume the underlying population is normal. catract
a. Is there any evidence to suggest that the mean time has decreased? Use a 5 0.01.
b. Find bounds on the p value associated with this test.