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A\&M again The president of the university plans a speech to an alumni group. He plans to talk about the proportion of students who responded in the survey that they are the first in their family to attend college, but the first draft of his speech treats that proportion as the actual proportion of current A\&M students who are the first in their families to attend college. Explain to the president the difference between the proportion of respondents who are first attenders and the proportion of the entire student body that are first attenders. Use appropriate statistics terminology.

Sampling students A professor teaching a large lecture class of 350 students samples her class by rolling a die. Then, starting with the row number on the die (1 to 6 ), she passes out a survey to every fourth row of the large lecture hall. She says that this is a simple random sample because everyone had an equal opportunity to sit in any seat and because she randomized the choice of rows. What do you think? Be specific.

Sampling satisfaction A company hoping to assess employee satisfaction surveys employees by assigning computer-generated random numbers to each employee on a list of all employees and then contacting all those whose assigned random number is divisible by 7 . Is this a simple random sample?

Survey students What problems do you see with asking the following question of students? "Are you the first member of your family to seek higher education?"

Student samples The university administration of Exercise 1 ? is considering a variety of ways to sample students for a survey. For each of these proposed survey designs, identify the problem. a. Publish an advertisement inviting students to visit a website and answer questions. b. Set up a table in the student union and ask students to stop and answer a survey.

Roper Through their Roper Reports Worldwide, GfK Roper conducts a global consumer survey to help multinational companies understand different consumer attitudes throughout the world. Within 30 countries, the researchers interview 1000 people aged 13-65. Their samples are designed so that they get 500 males and 500 females in each country. (www.gfkamerica.com) a. Are they using a simple random sample? Explain. b. What kind of design do you think they are using?

Student center survey For their class project, a group of statistics students decide to survey the student body to assess opinions about the proposed new student center. Their sample of 200 contained 50 first-year students, 50 sophomores, 50 juniors, and 50 seniors. a. Do you think the group was using an SRS? Why? b. What sampling design do you think they used?

Drug tests Major League Baseball tests players to see whether they are using performance-enhancing drugs. Officials select a team at random, and a drug- testing crew shows up unannounced to test all 40 players on the team. Each testing day can be considered a study of drug use in Major League Baseball. a. What kind of sample is this? b. Is that choice appropriate?

Gallup At its website (www.gallup.com), the Gallup Poll publishes results of a new survey each day. Scroll down to the end, and you'll find a statement that includes words suchas these: Results are based on telephone interviews with 1016 national adults, aged 18 and older, conducted March \(7-10,2014 \ldots .\) In addition to sampling error, question wording and practical difficulties in conducting surveys can introduce error or bias into the findings of public opinion polls. a. For this survey, identify the population of interest. b. Gallup performs its surveys by phoning numbers generated at random by a computer program. What is the sampling frame? c. What problems, if any, would you be concerned about in matching the sampling frame with the population?

In Exercises 17 ? to 23 ?, for the reports about statistical studies, identify the following items (if possible). If you can't tell, then say so - this often happens when we read about a survey. a. The population b. The population parameter of interest c. The sampling frame d. The sample e. The sampling method, including whether or not randomization was employed f. Who (if anyone) was left out of the study g. Any potential sources of bias you can detect and any problems you see in generalizing to the population of interest Mayoral race Hoping to learn what issues may resonate with voters in the coming election, the campaign director for a mayoral candidate selects one block from each of the city's election districts. Staff members go there and interview all the adult residents they can find.