InQuizitive Ch.7: Sampling: Estimating the Frequency of Behaviors and Beliefs

Select all of the sampling techniques that use meaningful categories from the population (e.g., demographics) and involve recruiting a certain number of participants from each of the categories in the population.

- over-sampling - stratified random sampling - quota sampling

Select all of the sampling techniques that lead to an unbiased sample

- stratified random sampling - cluster sampling - systematic sampling - multistage sampling - over-sampling

Scenario 1: A researcher at a nearby university wants to look at what teachers in a certain school district think about new policy changes. The researcher makes a list of all the schools in the district and uses a random number generator to select five schools from the district. Then the researcher interviews every teacher at each of those five schools. The researcher is using ______ in this study. Scenario 2: The campus safety committee has asked Professor Ibrahim to study bicycling on his campus. He trains two observers to rate the safety behaviors of cyclists at various locations around campus. He randomly selects 10 observation locations from the places where bicycles can be ridden on campus and randomly selects five 1-hour durations for each location. He has his observers make observations at each of the 10 places for each of the five durations. Dr. Ibrahim is using ______.

1. cluster sampling 2. multistage sampling

If a study's sample is not generalizable to the rest of the population, we would say that the study has ______ validity that is ______.

1. external 2. poor

A(n) ______ is the entire group of people that a researcher is interested in, while a(n) ______ is the smaller subset of that entire group that researchers study. A(n) ______ is conducted when a researcher investigates the entire group of people they are interested in.

1. population 2. sample 3. census

Scenario 1: A college administrator knows that 30% of the students at her college are from out of state, and she wants to make sure that she maintains this proportion in her survey about admission practices at the college. She has a list of all the out-of-state and in-state students and randomly selects 30 students from the out-of-state list and 70 students from the in-state list. She is using ______. Scenario 2: The directors of an annual community concert want to learn the musical preferences of the audience. The directors choose 2 and 6 from a random number generator and place a survey card on every sixth seat beginning with the second seat. All the cards are returned as the audience leaves. They are using ______.

1. stratified random sampling 2. systematic sampling

Identify the samples as either biased or unbiased.

Biased Sample(s): - Ami randomly selects phone numbers for a telephone survey and then asks the people she calls to recruit additional participants. - Dr. Lin recruits participants from her psychology class and then randomly assigns them to one of three conditions. - Zeynep posts advertisements for a study and then recruits every sixth person who contacts her. Unbiased Sample(s): - Travis randomly selects 15 major universities and then randomly selects 15 students from each of those universities. - Nasir selects telephone numbers from a random-digit dialer and then asks for the youngest male in the house who is at least 18.

Which of the following approaches increase external validity in a study?

Correct Answer(s): - using a probability sampling technique - using a representative sample Incorrect Answer(s): - increasing the sample size - using random assignment

Which of the following descriptions are relevant to probability or nonprobability samples?

Relevant to Probability Samples: - unbiased sample - externally valid sample - representative sample Relevant to Nonprobability Samples: - nonrandom sample - self-selected sample

Identify the true and false statements about generalizability and external validity.

True Statement(s): - A random sample of 1,000 people is enough to generalize to a population of 100 million people. False Statement(s): - External validity is always the highest priority in every type of claim. - A large sample is always more representative than a small sample. - If a finding does not generalize to other populations, it is invalid.

Dr. Lawrence is the director of Counseling Services at her university. She is planning to conduct a survey of 100 students to see how aware they are of the counseling services that the university offers. She wants the proportion of men and women in her sample to reflect the proportion at the university as a whole (55% women and 45% men). Dr. Lawrence plans to stand in the student center and ask people to participate until she has given the survey to 55 women and 45 men. Identify the true and false statements about Dr. Lawrence's study.

True Statement(s): - Dr. Lawrence is using quota sampling - Dr. Lawrence's study will have poor external validity False Statement(s): - Dr. Lawrence is using stratified random sampling - Dr. Lawrence is using a representative sample

Identify the true and false statements about probability and nonprobability sampling techniques.

True Statement(s): - Probability sampling techniques are a priority for frequency claims. - Only probability sampling techniques lead to externally valid results. False Statement(s): - Both probability and nonprobability sampling techniques allow researchers to generalize their results to the population of interest. - Nonprobability sampling techniques lead to larger sample sizes.

Label each sampling type as either biased or unbiased. Labels can be used more than once.

biased: - convenience sampling - snowball sampling - purposive sampling unbiased: - systematic sampling - stratified random sampling - probability sampling

Label each figure with the correct sampling technique.

cluster sampling: Results-3,5,6,10 (From research randomizer) multistage sampling: Results-3,5,6,10 (From research randomizer X2) stratified random sampling: Results based on meaningful categories + From research randomizer simple random sampling: Results- 2,4,6,12,13,16,18,22,23 (From research randomizer) quota sampling: Results based on meaningful categories

Jalon conducts a study to investigate whether anonymity affects the reported political opinions of college students. He recruits 156 participants from psychology classes and divides them into two groups. He asks the first group for their opinions about political issues and tells them that their responses will be completely anonymous. He asks the second group for their political opinions but does not tell them whether or not their opinions will be kept anonymous. Label the components of Jalon's study. Not all items will have a match.

sample: - psychology students sampling method: - convenience sampling population: - college students

The student government at a college is interested in determining how important intercollegiate sports are to the students. Because all students have e-mail accounts, the student government can send a survey to all the students at the college. About 50% of the students respond. What is the most likely bias in this sample?

self-selection

Label each example with the correct type of sampling.

snowball sampling: At the end of an online survey, participants are asked to tell their friends about it. simple random sampling: Researchers choose students at random by selecting the last digit of their student IDs. convenience sampling: Dr. Khan asks his intro psych students to fill out a survey on sleep quality and stress after class. multistage sampling: Researchers select children at three different elementary schools at random by birth date.

Karim is investigating the well-being of health care workers in his county during the COVID-19 pandemic. He notes that the health care workers in his county consist of 15% physicians, 50% nurses, and 35% administrative staff. He is considering several different sampling techniques for his study. Match each term to the sampling technique that Karim is considering.

stratified random sampling: Karim could randomly select 15 physicians, 50 nurses, and 35 administrative staff for his sample of 100 participants. quota sampling: Karim could visit a local hospital and pass out his survey to health care workers that walk by until he reaches his goal of 15 physicians, 50 nurses, and 35 administrative staff. multistage sampling: Karim could randomly select five hospitals from his county and then randomly select 50 health care workers from each of the selected hospitals. cluster sampling: Karim could randomly select five hospitals from his county and recruit all of the health care workers from those five hospitals. oversampling: Karim is concerned that 15 physicians might not give him a precise statistical estimate, so he could recruit more physicians and then adjust the results later.

Label each example with the correct type of sampling.

systematic sampling: A researcher approaches every fifth shopper who walks into a grocery store. oversampling: A survey interested in comparing prisoners to non-prisoners includes prisoners as 10% of its sample, even though they only make up 2.5% of the total population. quota sampling: Researchers conducting an online survey collect 50 men and 50 women in order to have equal gender representation. cluster sampling: Researchers select five hospitals at random and survey all the nurses in each hospital.

These are the results of a BuzzFeed poll about superstitions with 29,000 participants. To whom can we likely generalize the results of this poll?

the 29,000 participants of the BuzzFeed poll