Quiz 7

if a researcher studies every member of a population, the researcher is conducting?

a census

what is a sample?

a subgroup of the population

The following is what type of purposive sampling? looking at how cases are deviant can help define the category boundaries and shed light on the conventional case within a group.

extreme or deviant case sampling

______ ______ is a form of purposive sampling that takes the opposite approach to maximum variation. it seeks to sample people who are similar to one another from a population that is larger or more diverse

homogeneous sampling

______ ______ describe the primary traits of the target and accessible populations that will qualify someone as a subject

inclusion criteria

is when researchers alternate between theory development and collection of more data

iterative

______ _____ _____, involves selecting a sample in which the widest range of variation on the dimensions of interest is represented

maximum variation sampling

if some of the participants drop out of the experiment midcourse, _____ is said to have occurred

mortality

______ _____ do not guarantee that each person or element in the population has an equal chance of being selected

non probability sample

the selection of _____ ________ is made by nonrandom methods

non-probability samples

clinical researchers are often forced to use ______ ______, created when samples are chosen on some basis other than random selection

nonprobability samples

population averages are also called?

parameters

_____ ____, are studies designed to obtain preliminary information on how new treatments and measures work

pilot studies

____ is a defined aggregate of persons, objects, or events that meet a specified set of criteria

population

the larger group to which research results are generalized is called?

population

_____ is the ability to find significant differences when they exists

power

the magnitude of sampling errors?

precision

sampling techniques can be categorized as ?

probability or non probability

are created through a process of random selection?

probability samples

occurs when separating the population into four classes and then drawing random or systematic samples from each class in the proportion that exists in the population?

proportional stratified sample

_______ _____ is when the researcher hand picks subjects on the basis of specific criteria

purposive sampling

in _____ sampling, the researcher uses their knowledge of the population to select individuals who they believe will be good sources of information

purposive sampling (judgmental sampling).

_____ _____ is based on the judgement of the researchers; however, instead of trying to represent various types of people, it selects additional participants based on information needed to corroborate, extend, or revise the emerging theory.

theoretical sampling

T/F: a sample can only be representative of the accessible population, not necessarily the target population

true

T/F: cluster sampling involves successive random sampling of a series of units in the population.

true

T/F: simple random sample reduces bias by giving every member of the population a chance of being selected.

true

T/F: small, unbiased samples tend to yield more accurate results than biased samples, even if the sizes of the biased sample are larger

true

T/F: stratification increases the precision of estimates only when the stratification variable is closely related to the variables of experimental interest

true

a random sample is _______ in that each selection is independent, and no one member of the population has any more chance of being chosen than any other member

unbiased

_______ ____ indicate those factors that would prelude someone from being a subject

exclusion criteria

when its not possible to gain access to everyone. some portion of the target population that has a chance to be selected must be identified. which is called the?

accessible population

______ _______ ____ allows a population to be sampled geographically

area probability sampling

in which the next question varies depending on prior answer

branching

in ______ ______, researchers draw groups (or clusters) of participants instead of selecting individuals

cluster sampling

allows us to link members of the population to some already established grouping that can be sample

cluster sampling or multistage sampling

occurs when a sample is selected purposefully?

conscious biases

the most used and practical approach to convenience sampling is _________ _____, which involves recruiting all patients who meet the inclusion and exclusion criteria as they become available

consecutive sampling

the most common form of nonprobability sample is?

convenience sample or accidental sample

which method is when subjects are chosen on the basis of availability

convenience sample or accidental sample

_____ are the background characteristics that represent an indicator by which populations are described

demographics

is when random samples of adequate size from each category are selected

disproportional sampling

using ____ ___, a researcher can control the potential confounding effect of known characteristics of a population by guiding the sampling process so that an adequate number of subjects are obtained for each stratum

quota sampling

______-______ _____ involves the random selection of phone numbers based on multistage sampling of area codes and telephone exchanges

random-digit dialing

the ___ serves as the reference group for estimating characteristics of or drawing conclusions about the population

sample

________ ___ _________ is when the sample was not selected by any other logic than participants being available and willing.

sample of convenience

occurs when the individuals selected for a sample overrepresent or underrepresent certain population attributes that are related to the phenomenon under study?

sampling bias

error created by random sampling is simply called ____ ___ by statisticians

sampling error

the difference between sample averages and population averages is?

sampling error or sampling variation

the interval between selected elements is called?

sampling interval

_____ is when no more can be added or absorbed to something

saturation

_______ relies on simultaneous analysis, in which major and minor themes of the research emerge

saturation

the use of volunteers is called?

self-selection

table of random numbers is ___ ____ sampling?

simple random

giving every member of a population an equal chance of being included in the sample is called?

simple random sample

what kind of sampling is it when.. once a unit is selected it has no further chance of being selected.?

simple random sampling or sampling without replacement

______ ____ is a method that is often used to study sensitive topics, rare traits, personal networks, and social relationships

snowball sampling

sample averages are called?

statistics

stratification in conjunction with random sampling is?

stratified random sample

involves identifying relevant population characteristics, and partitioning members of a population into homogeneous, nonoverlapping subsets, or strata, based on characteristics

stratified random sampling

_______ _______ is when the researcher divides the total number of elements in the accessible population by the number of elements to be selected

systematic sampling

the method of sampling is essentially equivalent to simple random sampling is _____. in this type of sampling, every nth individual is selected

systematic sampling

are generated by computers and comprise thousands of digits (0-9) with no systematic order or relationship

table of random numbers

the first step in planning a study is to identify the?

target population

the overall group of people to which the researcher intends to generalize findings is called?

target population or reference population

random means?

that every unit in the population has an equal chance or "probability" of being chosen