Exam 18: A Roadmap for Analyzing Data

A physician and president of a Tampa Health Maintenance Organization (HMO)are attempting to show the benefits of managed health care to an insurance company. The physician believes that certain types of doctors are more cost-effective than others. To investigate this, the president obtained independent random samples of 20 HMO physicians from each of 4 primary specialtiesGeneral Practice (GP), Internal Medicine (IM), Pediatrics (PED), and Family Physicians (FP)and recorded the total charges per member per month for each. A second variable which the president believes influences total charges per member per month is whether the doctor is a foreign or US medical school graduate. To investigate this, the president also collected data on 20 foreign medical school graduates in each of the 4 primary specialty types described above. So information on charges for 40 doctors (20 foreign and 20 US medical school graduates)was obtained for each of the 4 specialties. The president has already found out that specialty types and origin of the medical degree do not interact to affect the charges. He has also found out special types do have an impact on average charges. Which of the following tests will be the most appropriate to find out which primary specialty has the highest charges?

The superintendent of a school district wanted to predict the percentage of students passing a sixth-grade proficiency test. She obtained the data on percentage of students passing the proficiency test (% Passing), daily mean of the percentage of students attending class (% Attendance), mean teacher salary in dollars (Salaries), and instructional spending per pupil in dollars (Spending)of 47 schools in the state. She believed that holding everything else constant, instructional spending per pupil had a positive but decreasing impact on percentage. Which of the following would be the most appropriate analysis to perform?

A supplier of silicone sheets for producers of computer chips wants to evaluate her manufacturing process. She takes samples of size 5 from each day's output and counts the number of blemishes on each silicone sheet for 20 days consecutive days. Which of the following would be the most appropriate analysis to perform?

An investor wanted to forecast the price of a certain stock. He collected the mean daily price for the stock over the past 10 years. Which of the following would be the most appropriate analysis to perform?

Every spring semester, the School of Business coordinates a luncheon for graduating seniors, their families, and friends with local business leaders. Corporate sponsorship pays for the lunches of each of the seniors, but students have to purchase tickets to cover the cost of lunches served to guests they bring with them. Data on the number of guests each graduating senior invited to the luncheon and the number of graduating seniors in each category were collected. A histogram can be used to present this information.

Every spring semester, the School of Business coordinates with local business leaders a luncheon for graduating seniors, their families, and friends. Corporate sponsorship pays for the lunches of each of the seniors, but students have to purchase tickets to cover the cost of lunches served to guests they bring with them. Data on the number of guests each graduating senior invited to the luncheon and the number of graduating seniors in each category were collected. You want to know the most popular number of guests brought by the graduating seniors. Which of the following will you compute?

A contractor wants to forecast the number of contracts in future quarters, using quarterly data on number of contracts during the 10-year period from 2001 to 2010. Which of the following would be the most appropriate analysis to perform?

A few years ago, Pepsi invited consumers to take the "Pepsi Challenge." Consumers were asked to decide which of two sodas, Coke or Pepsi, they preferred in a blind taste test. Pepsi was interesting in determining what factors played a role in people's taste preferences. One of the factors studied was the gender of the consumer. Data on the percentage of men and women depicting preference for Pepsi were collected. Which of the following tests will you use to find out if there is any difference in preference between the different gender groups?

Data on the amount of money made in a year by 1,000 families in a small town were collected. You want to know if the money made is normally distributed. Which of the following would you use?

The opinions (classified as "for," "neutral" or "against")of a sample of 200 people broken down by gender about the latest congressional plan to eliminate anti-trust exemptions for professional baseball. You can present this information using a scatter plot.

An airline wants to select a computer software package for its reservation system. Four software packages (1, 2, 3, and 4)are commercially available. The airline will choose the package that bumps as few passengers, on the average, as possible during a month. An experiment is set up in which each package is used to make reservations for 5 randomly selected weeks. (A total of 20 weeks was included in the experiment.)Which of the following tests will be the most appropriate?

Data on the amount of time spent studying for a particular exam at a high school were collected for 150 students. You want to know at least how much time half of the students spent studying for that exam. Which of the following would you compute?

An insurance company evaluates many variables about a person before deciding on an appropriate rate for automobile insurance. A representative from a local insurance agency selected a random sample of 15 insured drivers and recorded the amount of claims each made in the last 3 years. Based on this information, which of the following will you construct to learn about the mean amount of claims made by the company's customer?

A powerful women's group has claimed that men and women differ in attitudes about sexual discrimination. A group of 50 men (group 1)and 40 women (group 2)were asked if they thought sexual discrimination is a problem in the United States. Of those sampled, 11 of the men and 19 of the women did believe that sexual discrimination is a problem. Which of the following tests will you use to find out if there is any difference in attitudes about sexual discrimination?

Data on the amount of money made in a year by 1,000 families in a small town were collected. You want to know the difference in the amount of money made in that year by the middle 50% of the 1,000 families. Which of the following would you compute?

An economist is interested to see how consumption for an economy (in $ billions)is influenced by gross domestic product ($ billions)and aggregate price (consumer price index). Annual data from 30 years were collected. Which of the following would be the most appropriate analysis to perform?

A quality control engineer is in charge of the manufacture of computer disks. Two different processes can be used to manufacture the disks. He suspects that the Kohler method produces a greater proportion of defects than the Russell method. He samples 150 of the Kohler and 200 of the Russell disks and finds that 27 and 18 of them, respectively, are defective. If Kohler is designated as "Group 1" and Russell is designated as "Group 2," which of the following tests will you use to find out if the Kohler method is worse than the Russell method?

To test the effectiveness of a business school preparation course, 8 students took a general business test before and after the course. Suppose the before and after exam scores are both normally distributed. Which of the following tests will be the most appropriate?

Data were collected on the amount of detergent used in gallons in a month by 25 drive-through car wash operations in Phoenix. You can use a time-series plot to present this information.

The director of admissions at a state college is interested in seeing if admissions status (admitted, waiting list, denied admission)at his college is related to the type of community (urban, rural, suburban)in which an applicant resides. Which of the following tests will be the most appropriate?