Chapter 6 - Sampling

Question 1

probability sampling

Answer 1

sampling based on a process of random selection that gives each case in the population an equal/known chance of being included in the sample

Question 2

nonprobability sampling

Answer 2

methods of case selection other than random selection

Question 3

population

Answer 3

the total membership of a defined class of people, objects, or events

Question 4

sample

Answer 4

a subset of cases selected from a population

Question 5

probability

Answer 5

the likelihood that something will occur, which may vary from 0 to 100 percent

Question 6

random selection

Answer 6

a selection process that gives each element in a population an equal/known chance of being selected

Question 7

sampling without replacement

Answer 7

sampling procedure where once a case is selected, it’s not returned to the sampling frame

Question 8

sampling with replacement

Answer 8

sampling procedure where once a case is selected, it’s returned to the sampling frame

Question 9

probability distribution

Answer 9

distribution of the probabilities for a variable, which indicates the likelihood that each category or value of the variable will occur

Question 10

sampling error

Answer 10

the difference between an actual population value (%) and the population value estimated from a sample

Question 11

sampling distribution

Answer 11

a rhetorical distribution of sample results for all possible samples of a given size

Question 12

standard error

Answer 12

a statistical measure of the ‘average’ sampling error for a particular sampling distribution, which indicates how much sample results will vary from sample to sample

Question 13

normal curve

Answer 13

a bell-shaped distribution of data that characterizes many variables and statistics, such as the sampling distribution of a proportion or mean (aka normal distribution)

Question 14

confidence interval

Answer 14

a range (interval) within which a population value is estimated to be at a specific level of confidence

Question 15

target population

Answer 15

the population to which researchers would like to generalize their results

Question 16

sampling frame

Answer 16

an operational definition of the population that provides the basis for drawing a sample; ordinarily consists of a list of cases

Question 17

coverage error

Answer 17

the error that occurs when the sampling frame does not match the target population

Question 18

simple random sample

Answer 18

every case and every possible combination of cases has an equal chance of being included in sample

Question 19

stratified random sample

Answer 19

population is divided into strata/variable categories and independent random samples are drawn from each stratum

Question 20

weighting

Answer 20

procedure that corrects for the unequal probability of selecting one or more segments/strata of the populationc

Question 21

cluster sampling

Answer 21

population is broken down into natural groupings/areas and a random sample of clusters is drawn (multistage = sample at two or more stages)

Question 22

nonresponse error/bias

Answer 22

(in survey sampling) error that occurs when nonrespondents differ systematically from respondents

Question 23

case study

Answer 23

holistic analysis of a single person, group, or event by one or more research methods

Question 24

convenience sampling

Answer 24

selection of cases that are currently available

Question 25

purposive sampling

Answer 25

sampling involving careful and informed selection of typical cases or of cases that represent relevant dimensions of the population

Question 26

crowdsourcing

Answer 26

(online study sampling) practice of hiring a group of paid workers to participate in a study, through requests on crowdsourcing platform

Question 27

online panel

Answer 27

sample of people who agreed to participate in online surveys upon request

Question 28

snowball sampling

Answer 28

sampling procedure that uses a process of chain referral, where each contact is asked to identify additional members of the target population

Question 29

theoretical sampling

Answer 29

sampling used in qualitative research in which observations are selected in order to develop aspects of an emerging theory

Question 30

saturation

Answer 30

purposive/theoretical sampling -- the point at which new data cease to yield new information or theoretical insights