3.94 Online behavioral advertising.

The Federal Trade Commission Staff Report “Self-Regulatory Principles for Online Behavioral Advertising” defines behavioral advertising as “the tracking of a consumer’s online activities over time—including the searches the consumer has conducted, the webpages visited and the content viewed—to deliver advertising targeted to the individual consumer’s interests.” The report suggests four governing concepts for online behavioral advertising:

Write a report discussing your opinions concerning online behavioral advertising and the four governing concepts. Pay particular attention to issues related to the ethical collection and use of statistical data.

3.95 Confidentiality at NORC.

The National Opinion Research Center conducts a large number of surveys and has established procedures for protecting the confidentiality of their survey participants. For its Survey of Consumer Finances, it provides a pledge to participants regarding confidentiality. This pledge is available at scf.norc.org/Confidentiality.html. Review the pledge and summarize its key parts. Do you think that the pledge adequately addresses issues related to the ethical collection and use of data? Explain your answer.

3.96 What’s wrong?

Explain what is wrong in each of the following statements. Give reasons for your answers.

3.97 Price promotions and consumer behavior.

A researcher is studying the effect of price promotions on consumer behavior. Subjects are asked to choose between purchasing a single case of a soft drink for $4.00 or three cases of the same soft drink for $10.00. Is this study an experiment? Why? What are the explanatory and response variables?

3.98 What type of study?

What is the best way to answer each of the following questions: an experiment, a sample survey, or an observational study that is not a sample survey? Explain your choices.

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3.99 Choose the type of study.

Give an example of a question about your customers, their behavior, or their opinions that would best be answered by

3.100 Compare Pizza Hut with Domino’s.

Do consumers prefer pizza from Pizza Hut or from Domino’s? Discuss how you might make this a blind test in which neither source of the pizza is identified. Do you think that your blinding will be successful for all subjects? Describe briefly the design of a matched pairs experiment to investigate this question. How will you use randomization?

3.101 Coupons and customer expectations.

A researcher studying the effect of coupons on consumers’ expectations makes up two different series of ads for a hypothetical brand of cola for the past year. Students in a family science course view one or the other sequence of ads on a computer. Some students see a sequence of ads with no coupon offered on the cola, while others see regular coupon offerings that effectively lower the price of the cola temporarily. Next, the students are asked what price they would expect to pay for the cola.

3.102 Can you remember how many?

An opinion poll calls 2200 randomly chosen residential telephone numbers, and then asks to speak with an adult member of the household. The interviewer asks, “How many movies have you watched in a movie theater in the past 12 months?”

3.103 Marketing a dietary supplement.

Your company produces a dietary supplement that contains a significant amount of calcium as one of its ingredients. The company would like to be able to market this fact successfully to one of the target groups for the supplement: men with high blood pressure. To this end, you must design an experiment to demonstrate that added calcium in the diet reduces blood pressure. You have available 30 men with high blood pressure who are willing to serve as subjects.

3.104 A hot fund.

A large mutual funds group assigns a young securities analyst to manage its small biotechnology stock fund. The fund’s share value increases an impressive 43% during the first year under the new manager. Explain why this performance does not necessarily establish the manager’s ability.

3.105 Employee meditation.

You see a news report of an experiment that claims to show that a meditation technique increased job satisfaction of employees. The experimenter interviewed the employees and assessed their levels of job satisfaction. The subjects then learned how to meditate and did so regularly for a month. The experimenter reinterviewed them at the end of the month and assessed their job satisfaction levels again.

3.106 Executives and exercise.

A study of the relationship between physical fitness and leadership uses as subjects middle-aged executives who have volunteered for an exercise program. The executives are divided into a low-fitness group and a high-fitness group on the basis of a physical examination. All subjects then take a psychological test designed to measure leadership, and the results for the two groups are compared. Is this an observational study or an experiment? Explain your answer.

3.107 Does the new product taste better?

Before a new variety of frozen muffins is put on the market, it is subjected to extensive taste testing. People are asked to taste the new muffin and a competing brand and to say which they prefer. (Both muffins are unidentified in the test.) Is this an observational study or an experiment? Why?

3.108 Questions about attitudes.

Write two questions about an attitude that concerns you for use in a sample survey. Make the first question so that it is biased in one direction, and make the second question biased in the opposite direction. Explain why your questions are biased, and then write a third question that has little or no bias.

3.109 Will the regulation make the product safer?

Canada requires that cars be equipped with “daytime running lights,” headlights that automatically come on at a low level when the car is started. Some manufacturers are now equipping cars sold in the United States with running lights. Will running lights reduce accidents by making cars more visible?

3.110 Learning about markets.

Your economics professor wonders if playing market games online will help students understand how markets set prices. You suggest an experiment: have some students use the online games, while others discuss markets in recitation sections. The course has two lectures, at 8:30 A.M. and 2:30 P.M. There are 11 recitation sections attached to each lecture. The students are already assigned to recitations. For practical reasons, all students in each recitation must follow the same program.

3.111 How much do students earn?

A university’s financial aid office wants to know how much it can expect students to earn from summer employment. This information will be used to set the level of financial aid. The population contains 3478 students who have completed at least one year of study but have not yet graduated. The university will send a questionnaire to an SRS of 100 of these students, drawn from an alphabetized list.

3.112 Attitudes toward collective bargaining.

A labor organization wants to study the attitudes of college faculty members toward collective bargaining. These attitudes appear to be different depending on the type of college. The American Association of University Professors classifies colleges as follows:

Class I. Offer doctorate degrees and award at least 15 per year.

Class IIA. Award degrees above the bachelor’s but are not in Class I.

Class IIB. Award no degrees beyond the bachelor’s.

Class III. Two-year colleges.

Discuss the design of a sample of faculty from colleges in your state, with total sample size about 200.

3.113 Student attitudes concerning labor practices.

You want to investigate the attitudes of students at your school about the labor practices of factories that make college-brand apparel. You have a grant that will pay the costs of contacting about 500 students.

3.114 Treating drunk drivers.

Once a person has been convicted of drunk driving, one purpose of court-mandated treatment or punishment is to prevent future offenses of the same kind. Suggest three different treatments that a court might require. Then outline the design of an experiment to compare their effectiveness. Be sure to specify the response variables you will measure.

3.115 Experiments and surveys for business.

Write a short report describing the differences and similarities between experiments and surveys that would be used in business. Include a discussion of the advantages and disadvantages of each.

3.116 The product should not be discolored.

Few people want to eat discolored french fries. Potatoes are kept refrigerated before being cut for french fries to prevent spoiling and preserve flavor. But immediate processing of cold potatoes causes discoloring due to complex chemical reactions. The potatoes must, therefore, be brought to room temperature before processing. Fast-food chains and other sellers of french fries must understand potato behavior. Design an experiment in which tasters will rate the color and flavor of french fries prepared from several groups of potatoes. The potatoes will be freshly harvested, stored for a month at room temperature, or stored for a month refrigerated. They will then be sliced and cooked either immediately or after an hour at room temperature.

3.117 Quality of service.

Statistical studies can often help service providers assess the quality of their service. The U.S. Postal Service is one such provider of services. We wonder if the number of days a letter takes to reach another city is affected by the time of day it is mailed and whether or not the zip code is used. Describe briefly the design of a two-factor experiment to investigate this question. Be sure to specify the treatments exactly and to tell how you will handle lurking variables such as the day of the week on which the letter is mailed.

3.118 Mac versus PC.

Many people hold very strong opinions about the superiority of the computer they use. Design an experiment to compare customer satisfaction with the Mac versus the PC. Consider whether or not you will include subjects who routinely use both types of computers and whether or not you will block on the type of computer currently being used. Write a summary of your design, including your reasons for the choices you make. Be sure to include the question or questions that you will use to measure customer satisfaction.

3.119 Design your own experiment.

The previous two exercises illustrate the use of statistically designed experiments to answer questions of interest to consumers as well as to businesses. Select a question of interest to you that an experiment might answer, and briefly discuss the design of an appropriate experiment.

3.120 Randomization for testing a breakfast food.

To demonstrate how randomization reduces confounding, return to the breakfast food testing experiment described in Example 3.18 (page 146). Label the 30 rats 01 to 30. Suppose that, unknown to the experimenter, the 10 rats labeled 01 to 10 have a genetic defect that will cause them to grow more slowly than normal rats. If the experimenter simply puts rats 01 to 15 in the experimental group and rats 16 to 30 in the control group, this lurking variable will bias the experiment against the new food product.

Use software or Table B to assign 15 rats at random to the experimental group as in Example 3.20. Record how many of the 10 rats with genetic defects are placed in the experimental group and how many are in the control group. Repeat the randomization using different lines in Table B until you have done five random assignments. What is the mean number of genetically defective rats in experimental and control groups in your five repetitions?

3.121 Two ways to ask sensitive questions.

Sample survey questions are usually read from a computer screen. In a computer-aided personal interview (CAPI), the interviewer reads the questions and enters the responses. In a computer-aided self interview (CASI), the interviewer stands aside and the respondent reads the questions and enters responses. One method almost always shows a higher percent of subjects admitting use of illegal drugs. Which method? Explain why.

3.122 Your institutional review board.

Your college or university has an institutional review board that screens all studies that use human subjects. Get a copy of the document that describes this board (you can probably find it online).