2.8 Letters to the editor. You work for a local newspaper that recently reported on a bill that would make it easier to create charter schools in the state. You report to the editor that 201 letters have been received on the issue, of which 171 oppose the legislation. “I’m surprised that most of our readers oppose the bill. I thought it would be quite popular,” says the editor. Are you convinced that a majority of the readers oppose the bill? How would you explain the statistical issue to the editor?

2.9 Instant opinion. On January 30, 2015, the Los Angeles Times ran an online poll on its website and asked readers the question, “Which NFL team would you like to see come to L.A.?” Readers could click on one of three buttons (a picture of the Oakland Raiders logo, a picture of the San Diego Chargers logo, and a picture of the St. Louis Rams logo) to vote. In all, 11,908 (33%) selected the Oakland Raiders, 1939 (5%) selected the San Diego Chargers, and 22,138 (62%) selected the St. Louis Rams.

2.10 More instant opinion. In early 2015, the Drudge Report ran an online poll asking participants to vote for who they preferred for the Republican presidential candidate. The choices were Jeb Bush, Ben Carson, Chris Christie, Ted Cruz, Mike Huckabee, Sarah Palin, Rand Paul, Rick Santorum, Donald Trump, Rick Perry, Carly Fiorina, Marco Rubio, and Scott Walker. When the poll closed in February 2015, Scott Walker had received 199,095 votes (44%), Ted Cruz had received 58,844 votes (13%), Rand Paul had received 51,770 votes (12%), Ben Carson had received 37,945 votes (8%), Donald Trump had received 23,974 votes (5%), Sarah Palin had received 20,935 votes (5%), Jeb Bush had received 18,864 votes (4%), Marco Rubio had received 14,995 votes (3%), Rick Perry had received 6268 votes (1%), Mike Huckabee had received 6259 votes (1%), Chris Christie had received 5726 votes (1%), Rick Santorum had received 3038 votes (1%), and Carly Fiorina had received 2291 votes (1%).

2.11 Ann Landers takes a sample. Advice columnist Ann Landers once asked her divorced readers whether they regretted their decision to divorce. She received approximately 30,000 responses, about 23,000 of which came from women. Nearly 75% said they were glad they divorced, and most of them said they wished they had done it sooner. Explain why this sample is certainly biased. What is the likely direction of the bias? That is, is 75% probably higher or lower than the truth about the population of all adults who have been divorced?

2.12 We don’t like one-way streets. Highway planners decided to make a main street in West Lafayette, Indiana, a one-way street. The Lafayette Journal and Courier took a one-day poll by inviting readers to call a telephone number to record their comments. The next day, the paper reported:

Journal and Courier readers overwhelmingly prefer two-way traffic flow in West Lafayette’s Village area to one-way streets. By nearly a 7–1 margin, callers on Wednesday complained about the one-way streets that have been in place since May. Of the 98 comments received, all but 14 said no to one-way.

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2.13 Design your own bad sample. Your college wants to gather student opinion about parking for students on campus. It isn’t practical to contact all students.

2.14 A call-in opinion poll. In 2005, the San Francisco Bay Times reported on a poll in New Zealand that found that New Zealanders opposed the nation’s new gay-inclusive civil-unions law by a 3–1 ratio. This poll was a call-in poll that cost $1 to participate in. The San Francisco Bay Times article also reported that a scientific polling organization found that New Zealanders favor the law by a margin of 56.4% to 39.3%. Explain to someone who knows no statistics why the two polls can give such widely differing results and which poll is likely to be more reliable.

2.15 Call-in versus random sample polls. A national survey of TV network news viewers found that 48% said they would believe a phone-in poll of 300,000 persons rather than a random sample of 1000 persons. Of the viewers, 42% said they would believe the random sample poll. Explain to someone who knows no statistics why the opinions of only 1000 randomly chosen respondents are a better guide to what all people think than the opinions of 300,000 callers.

2.16 Choose an SRS. A firm wants to understand the attitudes of its minority managers toward its system for assessing management performance. Following is a list of all the firm’s managers who are members of minority groups. Use software or Table A to choose five to be interviewed in detail about the performance appraisal system. If you use Table A, begin at line 132 to choose the five to be interviewed.

2.17 Choose an SRS. Your class in ancient Ugaritic religion is poorly taught and the class members have decided to complain to the dean. The class decides to choose six of its members at random to carry the complaint. The class list appears here. Choose an SRS of six using either software or the table of random digits, beginning at line 112.

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2.18 An election day sample. You want to choose an SRS of 20 of Columbus, Ohio’s, 636 voting precincts for special voting-fraud surveillance on election day.

2.19 Is this an SRS? A university has 30,000 undergraduate and 10,000 graduate students. A survey of student opinion concerning health care benefits for domestic partners of students selects 300 of the 30,000 undergraduate students at random and then separately selects 100 of the 10,000 graduate students at random. The 400 students chosen make up the sample.

2.20 How much do students pay for rent? A university’s housing and residence office wants to know how much students pay per month for rent in off-campus housing. The university does not have enough on-campus housing for students, and this information will be used in a brochure about student housing. The population contains 12,304 students who live in off-campus housing and have not yet graduated. The university will send a questionnaire to an SRS of 200 of these students, drawn from an alphabetized list.

2.21 Apartment living. You are planning a report on apartment living in a college town. You decide to select three apartment complexes at random for in-depth interviews with residents. Use software or Table A, starting at line 112, to select a simple random sample of three of the following apartment complexes.

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2.22 How do random digits behave? Which of the following statements are true of a table of random digits, and which are false? Explain your answers.

2.23 Text in your vote. During the television broadcast on the Big Ten Network of a 2010 basketball game at Ohio State between Ohio State and Penn State, the announcers asked the following question: “Which player has meant the most to his team this year: Talor Battle of Penn State, Evan Turner of Ohio State, or other?” Viewers were asked to text in their votes. Later in the program, the results were announced. Evan Turner received 72% of the vote; Talor Battle, 26%; and “other,” 2%. Explain why this opinion poll is almost certainly biased.

2.24 More randomization. Most sample surveys call residential telephone numbers at random. They do not, however, always ask their questions of the person who picks up the phone. Instead, they ask about the adults who live in the residence and choose one at random to be in the sample. Why is this a good idea?

2.25 Racial profiling and traffic stops. The Denver Police Department wants to know if Hispanic residents of Denver believe that the police use racial profiling when making traffic stops. A sociologist prepares several questions about the police. The police department chooses an SRS of 200 mailing addresses in predominantly Hispanic neighborhoods and sends a uniformed Hispanic police officer to each address to ask the questions of an adult living there.

2.26 Random selection? Choosing at random is a “fair” way to decide who gets some scarce good, in the sense that everyone has the same chance to win. But random choice isn’t always a good idea—sometimes we don’t want to treat everyone the same because some people have a better claim. In each of the following situations, would you support choosing at random? Give your reasons in each case.