BA 1605 Spring 2013 Page 1 of 3
Assignment 1 Solutions
Due May 9, 2013
Total Points: 40
Chapter 2 # 2, 4, 10, 12, 16
2, a) Each row represents a different transaction (not customer or book). It is best described as a case.
b) 8 variables (3 points)
4. a) Transaction: categorical (identifier), ordinal
Customer ID: categorical (identifier), ordinal
Date: categorical, ordinal [ also accept quantitative, day]
ISBN Number: categorical (identifier), ordinal
Price: Quantitative, dollars
Coupon: Categorical, nominal
Gift: Categorical, nominal
Quantity: Quantitative, number of items
b) Cross Sectional (also accept time series, since date is included) (5 pts)
10. Store Locations: categorical
Weekly Sales: quantitative, dollars
Town Population: quantitative, number of people
Median town age: quantitative, years
Median town income: quantitative, years
Beer and Wine? Categorical
Variables are cross sectional [ accept if answer indicated sales represent time series] Data not from a designed survey or experiment (4 pts)
12. Type of Meat: categorical
Number of Calories: quantitative, calories
Serving Size: quantitative, ounces
Cross sectional data, not from designed survey or experiment (4 pts)
16. Customer Name: Categorical
ID Number: Categorical (Identifier)
Region of Country: Categorical
Date of Last Purchase: Categorical [also accept if response is quantitative, day]
Amount of Purchase: quantitative, dollars
Item Purchased: categorical
Cross Sectional Data [also accept id time series, since date is included] Data is not from a designed experiment. (4 points)
Chapter 3 # 2, 4, 6, 8, 12, 16, 20
2. a. F
b. F
c. F
d. T (4 points)
4. a. Population– All frequent flyer customers of the airline.
b. Sampling Frame–Airline database of frequent flier customers.
c. Parameter–Proportion who plan to use one of the airline’s new hubs in the next 6 months.
d. Sampling method–Simple random sample (SRS). (4 points)
6. a. No. It would be nearly impossible to get exactly 50 students from each class by selecting them at random from the student body.
b. . Stratified sampling (2 points)
8. The airline used stratified sampling (1 point)
12. a. The population of interest is all frequent flier customers of the airline.
b. Customers who have recently registered for the “Win the trip to Miami” contest on the Internet.
c. Accept a variety of responses. Only 1 problem required: The sampling frame may not be representative of all frequent fliers since those who are interested
in a trip to Miami may be more likely to fly there. Also, only those with Internet access would have been able to register for the contest. Since customers without Internet access may have different flying preferences than those with access, there is potential bias due to undercoverage. The survey question is biased (encouraging customers to respond in a particular way) and may lead to an inflated estimate of the true proportion of airline customers who would consider
traveling through the Miami hub. (3 points)
16. a. F
b. F
c. F
d. T (4 points)
20. a. This sample was a cluster sample, with the teams selected being the cluster.
b. It is a reasonable solution to the problem of randomly sampling players. You can sample an entire team at once relatively easily. (2 points)