Ch.7 Last Min

9. If researchers measure every tenth member of a population, they have a. conducted a census. b. collected a sample. c. increased internal validity. d. biased the study.

Answer: b. collected a sample.

31. How are quota sampling and stratified random sampling similar? a. Both identify subgroups that need to be studied. b. Both randomly sample subgroups to be studied. c. Both result in nonrepresentative samples. d. Both result in representative samples.

Answer: a. Both identify subgroups that need to be studied.

11. Which of the following is true of probability sampling? a. It is the best way to obtain a representative sample. b. It is the same as random assignment. c. It results in larger samples than nonprobability sampling. d. It should be used only when external validity is not the goal of the study.

Answer: a. It is the best way to obtain a representative sample.

28. Which of the following statements is true of random assignment and random sampling? a. Random assignment is necessary for internal validity, whereas random sampling is necessary for external validity. b. They both are necessary for frequency claims. c. They both mean the same thing. d. Random sampling is more important than random assignment.

Answer: a. Random assignment is necessary for internal validity, whereas random sampling is necessary for external validity.

56. Which of the following is an example of convenience sampling? a. Researchers recruited participants from online websites, such as Prolific Academic. b. Researchers oversampled Latinx participants for their study and adjusted their results. c. Researchers reached out to participants attending Gambler's Anonymous meetings. d. Researchers asked international college students to recommend other international students to participate in their study.

Answer: a. Researchers recruited participants from online websites, such as Prolific Academic.

21. Why are techniques like cluster sampling and multistage sampling just as externally valid as simple random sampling? a. They all contain elements of random selection. b. They all measure every member of the population of interest. c. They all use lists of all population members. d. They all rely on large samples.

Answer: a. They all contain elements of random selection.

45. Which of the following sampling techniques would you recommend to a researcher interested in studying rare individuals, like people who have been struck by lightning? a. snowball sampling b. purposive sampling c. quota sampling d. convenience sampling

Answer: a. snowball sampling

17. Convenience sampling relies on which of the following? a. studying people who are easy to find b. studying people who are willing to participate c. studying people who are typical d. studying people who are colleagues of the researcher

Answer: a. studying people who are easy to find

60. Which of the following is correct about sample size? a. A large sample size is more representative of the population than a small sample. b. A large sample size still needs to be a random sample in order to be generalizable. c. A sample size of 1,000 allows for the most statistically accurate conclusions. d. A sample size of 1,000 has the optimal balance of external validity and statistical accuracy.

Answer: b. A large sample size still needs to be a random sample in order to be generalizable.

46. Why might a researcher choose purposive sampling over systematic sampling? a. Purposive sampling is always cheaper. b. External validity is not vital to the researcher's study. c. Only purposive sampling allows the researcher to study a particular type of participant. d. The researcher does not have to specify a population of interest ahead of time.

Answer: b. External validity is not vital to the researcher's study.

27. For his research methods class project, Hiro is studying the effect of pet ownership on stress levels. Although a lot of research has been done on dog and cat owners, not much is known about other pets, so Hiro decides to study bird owners. Which of the following would demonstrate a purposive sampling technique? a. He contacts the Twitter followers of Dr. Oiseau, a famous biologist who studies birds. b. He recruits bird owners by e-mailing members of the National Bird Owners Association and asking for participants. c. His participants are all the people who have purchased birds at his local pet store in the past six months. d. He asks bird owners to give him the names of other bird owners.

Answer: b. He recruits bird owners by e-mailing members of the National Bird Owners Association and asking for participants.

36. When you are interrogating the external validity of a sample, which is the most important question to ask? a. How many people are in the sample? b. How was the sample collected? c. How were the participants measured? d. How many people are in the population?

Answer: b. How was the sample collected?

10. Which of the following is an example of a nonprobability sample? a. simple random sample b. convenience sample c. systematic sample d. cluster sample

Answer: b. convenience sample

22. The difference between a cluster sample and a multistage sample is a. cluster samples are probability samples; multistage samples are not. b. multistage samples sample both clusters and participants; cluster samples just sample clusters. c. cluster samples rely on clusters of participants; multistage samples collect data from participants at different stages. d. There is no difference between cluster samples and multistage samples.

Answer: b. multistage samples sample both clusters and participants; cluster samples just sample clusters.

18. Online surveys commonly suffer from which of the following? a. poor reliability b. self-selection c. probability sampling d. over sampling

Answer: b. self-selection

13. Dr. Chandler is a personality psychologist who is interested in studying the characteristics of people who report being abducted by UFOs. She finds several people in an online support group for UFO abductees to participate and asks them if they can provide the names and contact information of other people who have also been abducted. Upon contacting these new participants, she asks them to refer her to even more people they may know who have been abducted. This is an example of what kind of sampling? a. purposive sampling b. snowball sampling c. convenience sampling d. self-selection sampling

Answer: b. snowball sampling

54. Professor Adeyemi is examining well-being after retirement in a city, and it is important to have excellent external validity. If Professor Adeyemi obtains a sample that reflects the demographic proportions of their city, which of the following sampling techniques is most likely being used? a. cluster sampling b. stratified random sampling c. systematic sampling d. quota sampling

Answer: b. stratified random sampling

50. Studies that use nonprobability samples have ________ external validity. a. zero b. unknown c. guaranteed d. enhanced

Answer: b. unknown

23. The difference between a cluster sample and a stratified random sample is a. cluster samples study all possible clusters; stratified random samples randomly select strata. b. cluster samples use oversampling; stratified random samples use undersampling. c. cluster samples use randomly selected clusters; stratified random samples use predetermined strata. d. There is no difference between cluster samples and stratified random samples.

Answer: c. cluster samples use randomly selected clusters; stratified random samples use predetermined strata.

57. What information should you consider to examine the external validity of the claim, "Two-thirds of American college students sleep less than six hours a day"? a. if the sample size is large enough b. if random assignment was used in the study c. if the study used probability sampling d. if the sample includes non-American participants

Answer: c. if the study used probability sampling

12. Dr. Tanaka is an educational psychologist interested in students' attitudes toward science and the effect of those attitudes on performance on standardized tests. He chooses his local school district to study. There are 15 high schools, and he randomly chooses five. Then, of the 2,500 students in each of those five schools, he randomly recruits 250 students. This is an example of which of the following sampling techniques? a. snowball sample b. systematic sample c. multistage sample d. cluster sample

Answer: c. multistage sample

55. Dr. Choi is studying the extent to which Asian American mothers enforce gender roles at home. She wants to ensure that her sample includes 50 first generation, 50 second generation, and 50 third generation immigrants. If Dr. Choi obtains her particular sample by putting flyers in the local Asian grocery store, which of the following sampling techniques is she using? a. snowball sampling b. purposive sampling c. quota sampling d. stratified random sampling

Answer: c. quota sampling

19. Another term for probability sampling is a. purposive sampling. b. convenience sampling. c. random sampling. d. cluster sampling.

Answer: c. random sampling.

25. Which of the following results in an unrepresentative sample? a. systematic sample b. simple random sample c. snowball sample d. stratified random sample

Answer: c. snowball sample

53. Professor Adeyemi is examining well-being after retirement in a city, and it is important to have excellent external validity. Professor Adeyemi selects two random numbers, 4 and 6, and gets a list of all of the retired people in the city. If Professor Adeyemi obtains the sample by starting with the 4th person on the list and selecting every 6th person, which of the following sampling techniques is most likely being used? a. cluster sampling b. stratified random sampling c. systematic sampling d. quota sampling

Answer: c. systematic sampling

43. Which of the following may lead to a biased sample? a. using people who accept compensation (e.g., money) to participate b. using people who agree to participate c. using people who are readily available to the researcher d. using people who have participated in other research studies

Answer: c. using people who are readily available to the researcher

20. Why do studies that use probability samples have excellent external validity? a. They also ensure excellent internal validity. b. They study every member of the population of interest. c. They use a larger number of measures. d. All members of the population are equally likely to be represented in the sample.

Answer: d. All members of the population are equally likely to be represented in the sample.

30. For his research methods class project, Hiro is studying the effect of pet ownership on stress levels. Although a lot of research has been done on dog and cat owners, not much is known about other pets, so Hiro decides to study bird owners. Which of the following would demonstrate a snowball sampling technique? a. He contacts the Twitter followers of Dr. Oiseau, a famous biologist who studies birds. b. He recruits bird owners by e-mailing members of the National Bird Owners Association and asking for participants. c. His participants are all the people who have purchased birds at his local pet store in the past six months. d. He asks bird owners to give him the names of other bird owners.

Answer: d. He asks bird owners to give him the names of other bird owners.

51. Shoppers often leave reviews for products that they purchased online. Which of the following best describes the external validity of product reviews on an online shopping site? a. The external validity is high because this is a randomly selected sample of online shoppers. b. The external validity is high because online shoppers are more likely to be honest about their opinions. c. The external validity is low because online shoppers are more likely to change their mind. d. The external validity is low because this is a self-selected sample of online shoppers.

Answer: d. The external validity is low because this is a self-selected sample of online shoppers.

44. What do purposive, convenience, quota, and snowball sampling have in common? a. They are considered ethical sampling options. b. They are all probability sampling techniques. c. They produce large samples. d. They result in samples where some people are systematically left out.

Answer: d. They result in samples where some people are systematically left out.

24. Oversampling is a variant used in which of the following sampling techniques? a. simple random sampling b. cluster sampling c. convenience sampling d. stratified random sampling

Answer: d. stratified random sampling

26. Which of the following results in an unbiased sample? a. snowball sample b. convenience sample c. purposive sample d. systematic sample

Answer: d. systematic sample