Unit 5: Sampling techniques - Practice Quiz

1 What is sampling in psychological research?

2 What is the larger group from which a sample is selected called?

3 Why do researchers often use samples instead of studying entire populations?

4 A sample should ideally represent which group?

5 What is the main feature of probability sampling?

6 Which sampling method gives every population member an equal chance of selection?

7 In systematic sampling, researchers usually select:

8 What is the first step in many systematic sampling procedures?

9 Stratified sampling divides a population into groups called:

10 In stratified sampling, participants are selected from:

11 In cluster sampling, researchers select:

12 Which is an example of a cluster in cluster sampling?

13 What is the main feature of non-probability sampling?

14 Convenience sampling selects participants who are:

15 Purposive sampling involves selecting participants because they:

16 Quota sampling aims to include participants:

17 Snowball sampling is especially useful when participants are:

18 Which is an advantage of probability sampling?

19 Which is a common disadvantage of convenience sampling?

20 A major advantage of non-probability sampling is that it is often:

21 A psychologist wants to estimate the average stress score of all 8,000 students at a university. She studies 400 selected students and uses their average score as an estimate. What is the role of the 400 students?

22 A researcher defines the target population as all first-year psychology students at a university but collects data only from students attending one afternoon class. Which issue is most likely present?

23 A sample has the same proportion of undergraduate and postgraduate students as the university population, but it includes only students who volunteer. Which conclusion is most appropriate?

24 A researcher numbers every person in a population from 1 to 2,000 and uses a random-number generator to select 200 numbers without replacement. Which technique is being used?

25 From a list of 3,000 clients, a researcher selects every 15th client after randomly choosing a starting point between 1 and 15. What is the sampling interval?

26 A national survey first divides participants into age groups and then randomly selects people from each group in proportion to that group's population size. Which method is this?

27 A researcher randomly selects 10 schools and surveys every eligible student in those selected schools. What is the primary sampling method?

28 A population contains 60% women and 40% men. In a proportional stratified sample of 500 people, how many women should be selected?

29 Which situation most threatens the validity of a systematic sample?

30 Why might a researcher choose cluster sampling instead of simple random sampling when studying students across a country?

31 In a probability sample, one eligible person has a known selection probability of . What does this mean?

32 A researcher recruits participants by approaching people who are readily available in a shopping center. Which sampling method is being used?

33 A study of trauma survivors begins with three participants who refer other eligible survivors to the researcher. Which method is most appropriate to describe this procedure?

34 A survey requires 100 participants, including 50 women and 50 men, but interviewers recruit people nonrandomly until each target is reached. Which method is this?

35 A study on expert judgments selects clinical psychologists who have at least ten years of specialized experience. Which method is being used?

36 Which feature most clearly distinguishes quota sampling from proportional stratified random sampling?

37 A researcher uses simple random sampling rather than convenience sampling for a study intended to generalize to the entire population. What is the main advantage?

38 A researcher chooses cluster sampling and observes that participants within the same school have very similar stress scores. What is the likely consequence?

39 A convenience sample produces a very precise average for the people who participated, but most participants are psychology majors. What is the main limitation?

40 Which statement best explains a disadvantage of snowball sampling in research on a hidden population?

41 A psychologist wants to estimate the prevalence of test anxiety among 40,000 university students. The sampling frame omits students studying entirely online, and students with severe test anxiety are less likely to respond. Which statement best identifies the main threat to inference?

42 A study samples 100 people from a population of 10,000 using a genuinely random method. A second study samples 100 people from the same population using volunteers but obtains a very similar mean score. Which conclusion is most defensible?

43 A researcher samples intact therapy groups rather than individual clients. Clients within a group tend to resemble one another strongly. If the researcher analyzes the data as though all sampled clients were independent, what is the most likely consequence?

44 A sampling plan first defines the target population, then specifies an operational list from which units can actually be selected. Why is distinguishing these two concepts essential?

45 A school district has 80 schools and wants to sample 8 schools, surveying every student in each selected school. Students within schools are highly similar, and schools differ substantially in socioeconomic composition. Which design is most likely to reduce sampling variance compared with selecting 8 schools purely at random, assuming reliable school-level strata are available?

46 A population is divided into three strata containing 10%, 30%, and 60% of the population. A researcher samples 20%, 50%, and 30% from the respective strata and then computes an unweighted mean. What is the principal problem?

47 A researcher selects every 25th name after a random start from an ordered list of employees. The list is arranged in repeating cycles of 25 positions, and each cycle places night-shift workers in the same position. What risk is most serious?

48 In a two-stage design, 10 clinics are sampled with probability proportional to size, and then an equal number of patients is selected from each sampled clinic. Which statement is correct?

49 A population has 1,000 members. A simple random sample of 100 is selected without replacement. Compared with sampling 100 with replacement, which feature changes most directly?

50 A survey oversamples adolescents so that subgroup estimates are precise, then reports an overall prevalence without weights. The adolescent subgroup has a higher prevalence than adults. What direction of distortion is expected for the overall estimate?

51 A sampling frame lists households alphabetically by surname. A systematic sample uses an interval of 10 with a random start. If surname is associated with ethnicity and ethnicity is associated with depression scores, which claim is most accurate?

52 A researcher wants equal numbers of urban and rural participants, although the population is 70% urban and 30% rural. Participants are randomly selected within each area, and the final estimate uses population-proportion weights. What is this design?

53 A national survey selects regions, then schools within regions, then students within schools. Some schools refuse participation, and refusal rates differ by region. Which analysis is most appropriate?

54 A researcher recruits the first 200 visitors to a mental-health website and describes the result as an estimate for all adults with depression. Which limitation is most central?

55 A quota sample is designed to match the population on age and sex, but interviewers choose respondents within each quota at shopping centers. Which conclusion is most defensible?

56 To study undocumented migrant workers, a researcher begins with five participants and asks each to recruit peers. Recruitment chains remain concentrated within separate language communities. What is the key inferential concern?

57 A study uses purposive maximum-variation sampling to interview people with very different experiences of chronic pain. Which is the strongest justification for this approach?

58 A researcher recruits participants through an online advertisement offering a cash incentive. People with severe symptoms are disproportionately motivated to respond. Which adjustment would most directly address this problem?

59 For a rare psychological disorder, a researcher must choose between a simple random sample of the general population and purposive recruitment through specialist clinics. Which trade-off is most accurate?

60 A researcher compares a stratified design with a cluster design under equal costs. The population is heterogeneous overall but relatively homogeneous within neighborhoods. Which expectation is most defensible?