Chapter 6

In a study of Americans from a variety of professions were asked if they considered themselves left- handed, right-handed, or ambidextrous. The results are given below: Profession Right Left Ambidextrous Total Psychiatrist 101 10 118 Architect 115 26 148 Orthopedic Surgeon 121 5 6 132 Lawyer 83 16 6 105 Dentist 116 10 6 132 Total 536 67 32 635 1. Amongst Americans, 10% of the population is left-handed. Is there enough evidence from this data to show that more than 10% of those in these professions are left-handed? Make sure you show all the steps of this test. 2. Construct and interpret the 99% confidence interval for the proportion of Americans who are ambidextrous, based on this sample. 3. Is there enough evidence to conclude that proportion of left-handed orthopedic surgeons is less than the proportion of left-handed architects? Make sure you show all the steps of the test