scales
Nominal scale
type of measurement in which the categories represent qualitative differences in the variable being measured
predictive validity
efficacy wherein scores obtained from a measure accurately predict behavior according to a theory
parallel-forms reliability
The type of reliability established by comparing scores obtained by using two alternate versions of a measuring instrument to measure the same individuals and calculating a correlation between the two sets of scores.
The influence on the findings of a study from the experimenter’s expectations about the study. Experimenter bias is a type of artifact and threatens the validity of the measurement, as well as both internal and external validity.
experimenter bias
In a study, a participant’s tendency to respond in a way that is expected to corroborate the investigator’s hypothesis.
good subject role
opperational definition
procedure for indirectly measuring a variable that cannot be observed or measured directly
concurrent validity
efficacy wherein scores from a measure are directly related to scores from an established measure
test-retest reliability
The type of reliability established by comparing the scores obtained from two successive measurements of the same individuals and calculating a correlation between the two sets of scores.
A research study in which both the researcher and the participants are unaware of the predicted outcome for any specific participant.
double-blind research
In a study, a participant’s tendency to respond in a socially desirable fashion rather than truthfully.
apprehensive subject role
ratio scale
type of continuous measurement in which there is an absolute zero point
construct validity
efficacy wherein scores obtained from a measure behave exactly the same as the variable itself
split-half reliability
A measure of reliability obtained by splitting the items on a questionnaire or test in half, computing a separate score for each half, and then measuring the degree of consistency between the two scores for a group of participants.
Any potential cues or features of a study that (1) suggest to the participants what the purpose and hypothesis are, and (2) influence the participants to respond or behave in a certain way. Demand characteristics are artifacts and can threaten the validity of the measurement, as well as both internal and external validity.
demand characteristics
In a study, a participant’s tendency to respond in a way that is expected to refute the investigator’s hypothesis.
negativistic subject role
construct
hypothetical attribute or mechanism that helps explain and predict behavior
convergent validity
The type of validity demonstrated by a strong relationship between the scores obtained from two different methods of measuring the same construct.
The clustering of scores at the high end of a measurement scale, allowing little or no possibility of increases in value.
ceiling effect
Participants’ modification of their natural behavior in response to the fact that they are participating in a research study or the knowledge that they are being measured. Reactivity is an artifact and can threaten the validity of the measurement, as well as both internal and external validity.
reactivity
faithful subject roleIn a study, a participant’s attempt to follow experimental instructions to the letter and to avoid acting on the basis of any suspicions about the purpose of the experiment.
faithful subject role
face validity
concern whether a measure superficially appears to measure what it claims to measure
divergent validity
A type of validity demonstrated by using two different methods to measure two different constructs. Convergent validity then must be shown for each of the two constructs. Finally, there should be little or no relationship between the scores obtained for the two different constructs when they are measured by the same method.
The clustering of scores at the low end of a measurement scale, allowing little or no possibility of decreases in value; a type of range effect.
floor effect
In a study, a participant’s tendency to respond in a way that is expected to corroborate the investigator’s hypothesis.
good subject role
laboratoryA research setting that is obviously devoted to the discipline of science. It can be any room or space that the subject or participant perceives as artificial.
laboratory