Q1. For each problem, select the best response.

(a) In order to take a sample of 1200 people from a population, I first divide the population into men and women, and then take a simple random sample of 500 men and a separate simple random sample of 700 women. This is an example of a

A.convenience sampling.

B.stratified random sample.

C.a multistage sample.

D.a simple random sample.

E.randomized comparative experiment.

(b) A simple random sample of sizenis defined to be

A.a sample of sizenchosen in such a way that every unit in the population has a known nonzero chance of being selected.

B.a sample of sizenchosen in such a way that every set ofnunits in the population has an equal chance to be the sample actually selected.

C.a sample of sizenchosen in such a way that every unit in the population has the same chance of being selected.

D.All of the above. They are essentially identical definitions.

(c) A small college has 500 male and 600 female undergraduates. A simple random sample of 50 of the male undergraduates is selected, and, separately, a simple random sample of 60 of the female undergraduates is selected. The two samples are combined to give an overall sample of 110 students. The overall sample is

A.a stratified random sample.

B.a simple random sample.

C.a multistage sample.

D.convenience sampling.

E.a systematic sample.

Q2. For each problem, select the best response.

(a) Simple random sampling

A.reduces bias resulting from poorly worded questions.

B.reduces bias resulting from the behavior of the interviewer.

C.guarantees valid results.

D.offsets bias resulting from undercoverage and nonresponse.

E.None of the above.

(b) A news release for a diet product company reports: There's good news for the 65 million Americans currently on a diet. Its study showed that people who lose weight can keep it off. The sample was 20 graduates of the company's program who endorse it in commercials. The results of the sample are probably

A.unbiased, but they could be more accurate. A larger sample size should be used.

B.biased, overstating the effectiveness of the diet.

C.biased, understating the effectiveness of the diet.

D.None of the above.

Q3. A marketing research firm wishes to determine if the residents of Caldwell, Idaho, would be interested in a new downtown restaurant. The firm selects a simple random sample of 185 phone numbers from the Caldwell phone book and calls each household. Only 60 of those called are willing to participate in the survey, and 56 participants would support a new downtown restaurant.

(a) The sample in this survey is

A.all households in the Caldwell phone book.

B.all residents of Caldwell.

C.the 60 households that participated in the study.

D.the 185 phone numbers chosen.

E.None of the above.

(b) The chance that all 185 phone numbers chosen are located in one particular neighborhood in Caldwell is

A.exactly 0. Simple random sampling will spread out the locations of the phone numbers selected.

B.185 divided by the size of the population of Caldwell.

C.the same as for any other set of 185 phone numbers.

D.reasonably large due to the ''cluster'' effect.

E.None of the above.

(c) The population of interest is

A.the 60 households that participated in the study.

B.all households in the Caldwell phone book.

C.the 185 phone numbers chosen.

D.all residents of Caldwell.

E.None of the above.

Q4. Below is a bar graph of class standing for a Finance seminar containing five students who are either freshman, sophomores, juniors, or seniors. In the bar graph the bar for the juniors has been omitted.

\f\fAverage Number of Cigarettes per day Birth Weight of Child (in kilograms) 2.91 3.2? _I. \