Deck 5: Sampling: Surveys and How to Ask Questions

Question 1

Use the following information for questions:
Decide if the sample is representative (or not) of the population for the question of interest.

-What proportion of people intends to vote in the next presidential election?
Sample: 100 baseball fans at a baseball game.
Population: All voters in the next presidential election.

A) Representative
B) Not representative

Answer 1

Not representative

Question 2

Use the following information for questions:
Decide if the sample is representative (or not) of the population for the question of interest.

-What is the average age of people in Salt Lake City?
Sample: 10 people picked randomly from all people living in Salt Lake City.
Population: All people living in Salt Lake City.

A) Representative
B) Not representative

Answer 2

Representative

Question 3

Use the following information for questions:
Decide if the sample is representative (or not) of the population for the question of interest.

-What is the average number of letters on a page in Webster's unabridged dictionary?
Sample: The first page for each of the 26 letters in the alphabet.
Population: All pages in the dictionary.

A) Representative
B) Not representative

Answer 3

Not representative

Question 4

Use the following information for questions:
Decide if the sample is representative (or not) of the population for the question of interest.

-What is the average daily number of hours of sleep over a one year period?
Sample: Hours of sleep for 100 randomly selected students the night before an exam.
Population: All students in the university.

A) Representative
B) Not representative

Question 5

A national polling organization wishes to estimate the percentage of all teenagers who believe social security will 'be there' for them. The organization surveys a random sample of 1500 teenagers and 37% of this sample says that they believe social security will 'be there' for them. In this survey, what is the population of interest?

A) The 1500 teenagers who were surveyed.
B) Teenagers who believe social security will 'be there' for them.
C) All teenagers.
D) The people in the sample who believe social security will 'be there' for them.

Question 6

For which of the following situations would a census be more useful than a sample survey?

A) To determine what percent of the adults in a state are unemployed.
B) To estimate how many of the 200 physicians in a large city accept patients on welfare.
C) To estimate how many homeless people there are in a city.
D) To estimate how many of the students at a large university are in favor of a proposed fee increase to fund more parking.

Question 7

A census differs from a sample survey because

A) a sample survey is only done when measuring the units will destroy them.
B) a census is only done when measuring the units will destroy them.
C) in a sample survey the whole population is measured.
D) in a census the whole population is measured.

Question 8

Which of the following is not an advantage of a sample survey over a census?

A) A sample survey can be used when a census isn't possible.
B) It is much faster to collect a sample than a census.
C) A sample survey allows the researcher to devote the resources to getting the most accurate information possible.
D) Survey results have a good chance to be biased.

Question 9

For a survey of American diets a random sample of 1000 people were contacted. Of the 1000 people, 340 people completed the questionnaire. The results of this study, if applied to all Americans, are questionable because of

A) a large margin of error.
B) selection bias.
C) nonresponse bias.
D) response bias.

Question 10

A survey-taker randomly selected 1000 students who were studying in the library and found that 90% of these students were in favor of longer library hours. The results of this study, if applied to all students in the university, are questionable because of

A) lack of accuracy.
B) selection bias.
C) nonresponse bias.
D) response bias.

Question 11

A survey based on a random sample of 1000 students found that 1% of these students, when asked by the professor doing the survey, admitted to having cheated on at least one exam. The results of this study, if applied to all students in the university, are questionable because of

A) lack of accuracy.
B) selection bias.
C) nonresponse bias.
D) response bias.

Question 12

When the method for selecting subjects produces a sample that does not represent the population of interest, the problem is called

A) lack of accuracy.
B) selection bias.
C) nonresponse bias.
D) response bias.

Question 13

When a representative sample is selected but only a small proportion are actually contacted, the problem is called

A) lack of accuracy.
B) selection bias.
C) nonresponse bias.
D) response bias.

Question 14

When a representative sample is selected but respondents give answers that are different from their true opinions, the problem is called

A) lack of accuracy.
B) selection bias.
C) nonresponse bias.
D) response bias.

Question 15

A weight-loss company is trying to promote its product. Based on a sample of 10 of their clients they model the relationship between starting weight and weight after 4 weeks using their product. It turns out that these 10 clients were selected because they had lost a decent amount of weight in 4 weeks. Clients who had lost hardly any weight or even gained weight were not included for this study. The results of this study, if applied to all clients, are questionable because of

A) lack of accuracy.
B) selection bias.
C) nonresponse bias.
D) response bias.

Question 16

In the College of Engineering exams aren't proctored. Students are required to write out the University honor code. They sign their name to pledge that they didn't cheat. But the engineering professors cannot observe if students cheat or not. One way to collect data on this topic would be to use an "exit poll": Have a Graduate Student Instructor ask the students if they cheated on the exam after the student has left the exam room. The results of this study, if applied to all students in the College of Engineering, are questionable because of

A) lack of accuracy.
B) selection bias.
C) nonresponse bias.
D) response bias.

Question 17

People claim that only 5% of the students who take the introductory statistics course will continue their education in statistics. The Statistics Department believes that this value is too low and decides to take a sample of 20 students out of the 315 students registered that semester. Of the 20 students, 7 (or 35%) say they will continue to study more statistics. It turns out that the 20 students selected for this study were those that received the highest scores on the first quiz. The results of this study, if applied to all students who take the introductory statistics course, are questionable because of

A) lack of accuracy.
B) selection bias.
C) nonresponse bias.
D) response bias.

Question 18

A researcher is conducting a survey among students to determine their mean age. Data is collected by asking the age of a simple random sample of 150 students. The researcher simply asked the ages of these students. The results of this study, if applied to all students in the university, are questionable because of

A) lack of accuracy.
B) selection bias.
C) nonresponse bias.
D) response bias.

Question 19

Define the purpose of descriptive statistics.

Question 20

Define the purpose of inferential statistics.

Question 21

Use the following information for questions:
The next question are based on a survey of 500 students living in campus dormitories. Questionnaires were mailed to each of the 500 students. The questionnaire asked if they had ever stolen a bicycle or not. The sample proportion who said they had stolen a bicycle was used to estimate the proportion of all students on campus who had ever stolen a bicycle.

-Describe why selection bias is a problem for this survey.

Question 22

Use the following information for questions:
The next question are based on a survey of 500 students living in campus dormitories. Questionnaires were mailed to each of the 500 students. The questionnaire asked if they had ever stolen a bicycle or not. The sample proportion who said they had stolen a bicycle was used to estimate the proportion of all students on campus who had ever stolen a bicycle.

-Describe why response bias could be a problem for this survey.

Question 23

Use the following information for questions:
The next question are based on a survey of 500 students living in campus dormitories. Questionnaires were mailed to each of the 500 students. The questionnaire asked if they had ever stolen a bicycle or not. The sample proportion who said they had stolen a bicycle was used to estimate the proportion of all students on campus who had ever stolen a bicycle.

-Describe why non-response bias could be a problem for this survey.

Question 24

A survey is planned to be done by contacting a random sample of people who have bought something over the Internet; the question would ask whether sales made over the Internet should be taxed or not. The purpose is to estimate the proportion of all Americans who would support an Internet sales tax. Explain why selection bias would be a problem for this survey.

Question 25

A random sample of registered 500 voters was taken, and 80% responded that they had voted in the last presidential election. Explain why response bias may be a problem for this survey.

Question 26

A telephone survey was planned to ask people whether they planned to watch the next Super Bowl. Explain why non-response bias may be a problem for this survey.

Question 27

Studies have shown that growing numbers of young girls are beginning to use steroids. At a committee hearing, a survey by the Centers for Disease Control and Prevention of high school students was cited, in which 7.3 percent of ninth-grade girls said they had used illegal steroids. One critic of the results objected to the methodology of the survey, which used an anonymous questionnaire and did not ask what substances were used. He suggested that some of the teenagers might have thought incorrectly that were using anabolic steroids. What type of bias is being raised by this issue?

Question 28

Which one of the following statements is true about sample size and margin of error?

A) Increasing the sample size of a survey decreases the margin of error.
B) Increasing the sample size of a survey increases the margin of error.
C) Increasing the sample size of a survey does not change the margin of error.
D) Increasing the sample size of a survey only changes the margin of error if there is an error (a mistake) in the way the survey is conducted.

Question 29

A randomly selected sample of 1,000 college students was asked whether they had ever used the drug Ecstasy. Sixteen percent (16% or 0.16) of the 1,000 students surveyed said they had. Which one of the following statements about the number, 0.16 is correct?

A) It is a sample proportion.
B) It is a population proportion.
C) It is a margin of error.
D) It is a randomly chosen number.

Question 30

A random sample of Americans at least 65 years old showed that 32% believe their health is extremely important. If the sample size was 100, approximately what was the margin of error?

A) 1%
B) 5%
C) 10%
D) 15%

Question 31

A random sample of 1001 Americans aged 18-24 years showed that 51% believe their health is extremely important. An approximate 95% confidence interval for the proportion of all 18-24 year olds who believe that their health is extremely important is

A) between 41% and 61%.
B) between 46% and 56%.
C) between 48% and 54%.
D) between 50% and 52%.

Question 32

A random sample of Americans showed that 4% believe their health care is excellent. If the conservative margin of error was 12.5%, what was the sample size?

A) 25
B) 36
C) 49
D) 64

Question 33

A Gallup poll reported that 88% of Americans say they have health insurance. If the sample size was 2500, an approximate 95% confidence interval for the proportion of all Americans who say they are insured is

A) between 80% and 96%.
B) between 84% and 92%.
C) between 86% and 90%.
D) between 87.3% and 88.7%.

Question 34

A Gallup poll reported that 58% of Americans say they are satisfied with the costs of healthcare. If the margin of error was 5%, approximately what was the sample size?

A) 10
B) 200
C) 400
D) 1600

Question 35

Use the following information for questions:
According to a Gallup poll, about 90% of all American adults owned a cell phone at the time of the poll. The results are based on telephone interviews with a randomly selected national sample of 998 adults, 18 years and older. The margin of error was reported to be 3.5%.

-What was the population of interest in this Gallup Poll?

A) All American adults who own cell phones.
B) All American adults.
C) The 998 adults who participated in the survey.
D) The participants in the survey who owned cell phones.

Question 36

Use the following information for questions:
According to a Gallup poll, about 90% of all American adults owned a cell phone at the time of the poll. The results are based on telephone interviews with a randomly selected national sample of 998 adults, 18 years and older. The margin of error was reported to be 3.5%.

-Which of the following statements correctly interprets the reported margin of error of 3.5%?

A) In about 95% of all random samples of this size from the same population, the difference between the sample percent and the population percent will be less than 3.5%.
B) In about 3.5% of all random samples of this size from the same population, the sample percent will equal the population percent.
C) The probability that a 95% confidence interval based on this poll does not cover the population proportion is 3.5%.
D) In about 95% of all random samples of this size from the same population, the difference between the sample percent and the population percent will be more than 3.5%.

Question 37

A recent poll reported that 62% of all college students believe there is extraterrestrial life. The 95% margin of error for the poll was 4%. Which of the following statements is correct?

A) We can be certain that the percentage of all college students who believe there is extraterrestrial life is in the interval 58% to 66%.
B) The chance is 95% that at least 62% of all college students believe there is extraterrestrial life.
C) With 95% confidence we can say that the percentage of all college students who believe there is extraterrestrial life is between 58% and 66%.
D) The chance is 5% that at least 62% of all college students believe there is extraterrestrial life.

Question 38

A polling agency conducted a survey of 100 doctors on the question: "Are you willing to treat women patients with the recently approved pill RU-486?" The conservative margin of error associated with the 95% confidence interval for the percent who say 'yes' is

A) 50%.
B) 10%.
C) 5%.
D) 2%.

Question 39

In a random sample of n = 400 people, 40% say they have allergies. The conservative margin of error is reported to be 5%. What is a 95% confidence interval for the percent of the population that has allergies?

A) 25% to 55%
B) 30% to 50%
C) 35% to 45%
D) 40% to 45%

Question 40

Which one of the following statements is true?

A) Increasing the sample size of a survey decreases the margin of error.
B) Increasing the sample size of a survey increases the margin of error.
C) Increasing the sample size of a survey decreases the impact of response bias.
D) Increasing the sample size of a survey increases the impact of response bias.

Question 41

Recently a group of adults who swim regularly for exercise was evaluated for depression. Each person's depression status was recorded as either currently depressed, likely to get depressed, or not depressed. It turned out that these swimmers were less likely to be depressed than the general population. What sample size was used if the margin of error was about 6%?

A) n = 17
B) n = 36
C) n = 278
D) n = 400

Question 42

A student organization is trying to decide whether or not to offer more movies on campus. A random sample of students is about to be asked if they are in favor of more free movies on campus. What sample size would be needed to provide a margin of error of about 3%?

A) n = 33
B) n = 1000
C) n = 1001
D) n = 1112

Question 43

During the graduation ceremonies, a student who writes for the school newspaper decides to sample some of the graduating seniors for a quick survey. After the students receive their diploma and step off the stage, he will ask them the question: "Have you already been accepted to college at this point?" What sample size would be needed to provide a margin of error of about 10%?

A) n = 1
B) n = 10
C) n = 100
D) n = 1000

Question 44

A random sample of 2000 students showed that 800 were in favor of more movies on campus. Report the results of this poll using the sample proportion and margin of error.

Question 45

A random sample of 400 students involved in club activities showed that 250 were women. What is an approximate 95% confidence interval for the proportion of all students involved in club activities who are women?

Question 46

Two researchers are each conducting a study to estimate a certain population proportion. Researcher A proposes to take a random sample of n = 1000 units from his population of 1 million units. Researcher B proposes to take a random sample of n = 2000 units from his population of 2 million units. For which researcher will the margin of error be the smallest? Explain.

Question 47

Use the following information for questions:
A claim was made that at a local college only 5% of the students that take the introductory statistics course will continue their education in statistics. The Statistics Department at the college believes that this value is too low and decides to conduct a sample survey of 100 students that completed the introductory course the previous term.
-Identify the population.

Question 48

Use the following information for questions:
A claim was made that at a local college only 5% of the students that take the introductory statistics course will continue their education in statistics. The Statistics Department at the college believes that this value is too low and decides to conduct a sample survey of 100 students that completed the introductory course the previous term.
-Of the 100 selected students, 35 reported that they plan to continue an education in statistics. Report the results of this poll using the sample proportion and margin of error.

Question 49

Use the following information for questions:
According to a survey conducted by the Association for Dressings and Sauces (this is an actual association!), 85% of American adults eat salad at least once a week, so that 15% of American adults eat no salad at all! A nutritionist suspects that the percentage (of no-salad eaters) is wrong. She conducts a survey among a sample of adults in her area to test this idea.
-What would be the approximate margin of error if the researcher randomly sampled 2000 adults?

Question 50

Use the following information for questions:
According to a survey conducted by the Association for Dressings and Sauces (this is an actual association!), 85% of American adults eat salad at least once a week, so that 15% of American adults eat no salad at all! A nutritionist suspects that the percentage (of no-salad eaters) is wrong. She conducts a survey among a sample of adults in her area to test this idea.
-What sample size would be needed to provide a margin of error no larger than 2%?

Question 51

Which of the following is not true about drawing a simple random sample from a population?

A) It protects against hidden or unknown biases.
B) It gives each member of the population an equal chance of being selected.
C) It requires that the population be represented by a list.
D) It requires that the size of the sample be no more than 5% of the size of the population.

Question 52

A company has 500 employees and would like to select a simple random sample of 25 of them for a study. Of the following, only one fits the definition of a simple random sample. Which one is it?

A) Randomly choose one person whose last name begins with A, one with B, and so on, omitting X because it's least common.
B) Randomly choose 25 pages from the employee directory, then choose the first person listed on each of those pages.
C) Number the employees from 1 to 500 based on seniority and randomly choose one person from the first 20 names on the list, one from the next 20, and so on.
D) Number the employees from 1 to 500 in random order and choose the first 25 names on the list.

Question 53

A class consists of 30 students and the instructor wants to take a simple random sample of 5 students from this class. Which of the following represent the labels that are needed in order to select the sample using a random number table?

A) 1, 2, 3, 4, 5.
B) 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, …, 30.
C) 01, 02, 03, 04, 05, 06, 07, 08, 09, 10, …, 30.
D) 01, 02, 03, 04, 05.

Question 54

A class consists of 30 students and the instructor wants to take a simple random sample of 5 students from this class. The students are labeled 01 to 30 for the selection process. Which of the following possible samples of size n = 5 is most likely to be selected?

A) 11, 18, 10, 08, 25.
B) 05, 10, 15, 20, 25.
C) 01, 02, 03, 04, 05.
D) None of the above, as they are all equally likely samples.

Question 55

A population consists of 500 members and a simple random sample of 100 members is to be selected. Which of the following represents the most efficient method for labeling the members for selecting the sample using a random number table?

A) 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, …, 99, 100.
B) 1 = labels 001 and 501, 2 = labels 002 and 502, … 500 = labels 500 and 000.
C) 001, 002, 003, …, 499, 500.
D) 1 = labels 001, 101, 201, 301, …, 901; 2 = labels 002, 102, 202, 302, …, 902; and so on.

Question 56

Use the following information for questions:
The next question are based on the following row of digits from a random number table. Use these digits to select a random sample following steps 1 through 4 in the text.
00157 $\quad$ 37071 $\quad$ 79553 $\quad$ 31062 $\quad$ 42411 $\quad$ 79371 $\quad$ 25506 $\quad$ 69135

-Suppose that a group of 10 students are numbered from 0 to 9. Draw a simple random sample of 5 students by starting with the digit 1 in the first string of digits 00157. Which 5 students would be selected?

Question 57

Use the following information for questions:
The next question are based on the following row of digits from a random number table. Use these digits to select a random sample following steps 1 through 4 in the text.
00157 $\quad$ 37071 $\quad$ 79553 $\quad$ 31062 $\quad$ 42411 $\quad$ 79371 $\quad$ 25506 $\quad$ 69135

-Suppose that a group of 50 students are numbered from 01 to 50. Draw a simple random sample of 5 students by starting with the digit 15 from the first string of digits 00157. Which 5 students would be selected?

Question 58

Use the following information for questions:
The next question are based on the following row of digits from a random number table. Use these digits to select a random sample following steps 1 through 4 in the text.
00157 $\quad$ 37071 $\quad$ 79553 $\quad$ 31062 $\quad$ 42411 $\quad$ 79371 $\quad$ 25506 $\quad$ 69135

-Suppose that a group of 20 students are numbered from 01 to 20. Draw a simple random sample of 5 students by starting with the digit 01 from the first string of digits 00157. Which 5 students would be selected? (Do not use the more efficient method of, for instance, choosing number 1 if 21, 41, 61, or 81 is the random number.)

Question 59

Use the following information for questions:
First Avenue is in desperate need of repaving. The county road commission would like to survey the people who live along this road. They have a list available of all 176 household addresses along First Avenue with the addresses listed in numerical order by address.
-Explain an efficient labeling scheme for taking a simple random sample of 20 household addresses.

Question 60

Use the following information for questions:
First Avenue is in desperate need of repaving. The county road commission would like to survey the people who live along this road. They have a list available of all 176 household addresses along First Avenue with the addresses listed in numerical order by address.
-Using the following stream of random digits, determine the first five selected addresses that would be part of the simple random sample of 20 addresses.
16332 40139 64701 46355 62340 22011 47257 74877

Question 61

Use the following information for questions:
Olivia wants to learn a foreign language. To get an idea of how satisfied other students were after taking a foreign language course, she decides to take a random sample of 20 students.

-If Olivia randomly selects 5 students from French, 5 from German, 5 from Spanish, and 5 from Chinese, the sampling method is a

A) simple random sample.
B) stratified random sample.
C) cluster sample.
D) systematic sample.

Question 62

Use the following information for questions:
Olivia wants to learn a foreign language. To get an idea of how satisfied other students were after taking a foreign language course, she decides to take a random sample of 20 students.

-If Olivia randomly selects one class among all the foreign language classes taught that year, and then interviews all students in that class, the sampling method is a

A) simple random sample.
B) stratified random sample.
C) cluster sample.
D) systematic sample.

Question 63

Use the following information for questions:
Olivia wants to learn a foreign language. To get an idea of how satisfied other students were after taking a foreign language course, she decides to take a random sample of 20 students.

-If Olivia randomly selects 20 students among all students taking a foreign language class that year, the sampling method is a

A) simple random sample.
B) stratified random sample.
C) cluster sample.
D) systematic sample.

Question 64

Use the following information for questions:
Olivia wants to learn a foreign language. To get an idea of how satisfied other students were after taking a foreign language course, she decides to take a random sample of 20 students.

-If Olivia selects every 100^th student from a list of the 2000 students who took a foreign language that year, the sampling method is a

A) simple random sample.
B) stratified random sample.
C) cluster sample.
D) systematic sample.

Question 65

A magazine printed a survey in its monthly issue and asked readers to fill it out and send it in. Over 1000 readers did so. This type of sample is called a

A) cluster sample.
B) stratified sample.
C) simple random sample.
D) self-selected sample.

Question 66

A population of taxpayers is divided into five income levels and a simple random sample is selected from each one for an audit. This is an example of a _________ sample.

A) cluster
B) stratified
C) simple random
D) systematic

Question 67

Taxpayers in a population are listed in order of increasing income, with people with the lowest incomes listed first. A sample is selected by randomly choosing one of the first 100 names, then choosing every 100^th name from that point forward. This is an example of a __________ sample.

A) stratified
B) cluster
C) simple random
D) systematic

Question 68

Children at a Kindergarten school are divided into three groups: Those who are the oldest/first child (there are 200 of them, call this Group I), those who are the second child (there are 150, call this Group II), and those who are the third (or even fourth or fifth) child (there are 75, call this Group III). The social worker at the school will take a sample to find out how many sleepovers they have had (without parents) at a friend's house. She suspects that first-borns do not get as many as later children, so she decides to take a simple random sample of 15 children from each of the three groups. What sampling technique will be used to obtain the sample of children?

A) stratified
B) cluster
C) simple random
D) multi-stage

Question 69

A librarian wants to gather data on the number of times books of fiction are checked out during the year. The library has 2000 books of fiction, of which 500 are murder mysteries, 400 are science fiction, and the rest are "other". She decides to sample 120 books. Suppose the librarian decides to take a simple random sample of 30 books from the murder mystery category, 24 from the science fiction category, and the remaining 66 from the other category. What sampling technique was used?

A) simple random
B) cluster
C) stratified
D) multi-stage

Question 70

A company that produces electronics (stereos, TV's, DVD players, etc.) is thinking about adding an incentive program to the contracts of its employees. To learn about the opinion of its employees regarding this idea, a survey will be sent out to a sample of the employees. To ensure that employees of all three plants are represented in the survey, the statistician decides to take a sample of employees from each of the three plants. At each plant, a list is available of all employees. A 1-in-20 systematic sample will be taken from each plant. What sampling technique is being used to sample the employees?

A) simple random
B) cluster
C) stratified
D) multi-stage

Question 71

Use the following information for questions:
The Michigan Department of State Police keeps track of the number of points received for various traffic violations by Michigan drivers. The department is interested in examining the relationship between the number of points received and the insurance premium. The following chart shows the number of drivers in each category of points according to the records from last year. The department will take a simple random sample of 3% of the drivers in the Low category and 2% of the drivers in the other two categories.

-How many drivers will be included in the study?

A) 574
B) 24
C) 540
D) 399

Question 72

Use the following information for questions:
The Michigan Department of State Police keeps track of the number of points received for various traffic violations by Michigan drivers. The department is interested in examining the relationship between the number of points received and the insurance premium. The following chart shows the number of drivers in each category of points according to the records from last year. The department will take a simple random sample of 3% of the drivers in the Low category and 2% of the drivers in the other two categories.

-What sampling method will be used to obtain the sample?

A) simple random
B) cluster
C) stratified
D) multi-stage

Question 73

There are five cities in a politician's district but redistricting has been proposed for the state. The politician would like to know which city he should try to remove from his district. He plans to conduct a survey to find out his approval rating. Which one of the following sampling plans would be most useful for his purposes?

A) Take a stratified sample with political parties as the strata.
B) Take a stratified sample with the five cities as the strata.
C) Take a simple random sample across his district.
D) Take a cluster sample with the five cities as clusters.

Question 74

Which of the following is the best example of a population from which a cluster sample would be easier to obtain that a simple random sample?

A) Passengers who will be flying in the upcoming week on a certain airline.
B) Registered drivers in a certain state.
C) Employees of a large company.
D) Members of a national organization.

Question 75

One problem with using random digit dialing to get a representative sample of households in a city is that

A) the method can only be used to get a sample for the whole country.
B) households with multiple telephones on the same line will be over-represented.
C) households with multiple phone numbers will be over-represented.
D) households with unlisted phone numbers will not be represented.

Question 76

Use the following information for questions:
These questions pertain to how to collect a random sample of 800 airline passengers from 100 particular flights leaving San Francisco International Airport. Assume there are 200 passengers aboard each flight.
-Describe how to draw the sample as a stratified random sample, using the 100 flights as the strata.

Question 77

Use the following information for questions:
These questions pertain to how to collect a random sample of 800 airline passengers from 100 particular flights leaving San Francisco International Airport. Assume there are 200 passengers aboard each flight.
-Describe how to draw the sample as a cluster random sample, using flights as the cluster.

Question 78

Use the following information for questions:
These questions pertain to how to collect a random sample of 800 airline passengers from 100 particular flights leaving San Francisco International Airport. Assume there are 200 passengers aboard each flight.

-Describe how to draw the sample as a systematic sample from these flights.

Question 79

Both cluster and stratified sampling rely on sub-groups in the population. If the sub-groups are all very similar (they can all be considered mini-populations), which sampling method would be preferred?

Question 80

On a chilly spring afternoon, 10 lab sections of a statistics class all have full attendance. The 10 lab sections each have the same number of students attending. A survey is about to be administered to a sample of the students. It has been decided to first randomly select 3 of the 10 lab sections and then give the evaluation to a simple random sample of 25% of the students in those selected lab sections. What sampling technique is being used for this survey?