2: 4 Vailidites Flashcards
Construct validity
-adequacy of operational definition
-does OD tap into conceptual variable being studied
-evaluate quality of operational definition
-abstract variables must infer from objective measurements.
Important for all
Statistical validity
Do the numbers support claim -are appropriate stats used -margin of error -what is the strength of an association -is conclusion stat. Significant. Type 1 error: false positive; low probability that finding is due only to chance Type 2 error: false negative; null result was a miss Important for all
External validity
Genealizability to other people/contexts
-threatens by anything that may make data unrepresentative
-threats to generalizing beyond small: biased sampling, self-selection/volunteer bias
-threats to generalizing beyond the context: subject reactivity, highly controlled lab setting, unique measures or manipulating
More important when generalizability is emphasized(frequency or association)
Internal validity
Causal relationship can be inferred
-no possible alternative causal explanations
ESSENTIAL FOR CAUSAL CLAIMS
-degree to which ensures only IV manipulation is responsible for changes in DV
-control EV: eliminates as alt factors(confounds), CV threaten internal validity
Interrogating frequency claims
Construct: how well was variable measured
Stat: how large sample size and margin of error?, confidence true value of a proportion or avg lies within range
External ESSENTIAL: generalize from sample to intended population? Sample representative of population? How was it acquired?
Interrogating association claims
Construct: how well was each variable measured?
Stat: how strong is association? Is stat. Significant? Avoid type 1 and 2 errors
External: to what can we generalize? Does apply to other? Consider representativeness of sample and setting.
Interrogating causal claims
Construct: how well was IV manipulated? How well was DV measured?
Stat: how big is diff? Is stat. Significant? Avoid Type 1 and 2 errors
External: (many not be prioritized)
To whom or what generalize effect? Does apply to other people or occur in other contexts?
Consider representativeness of sample and setting
Internal ESSENTIAL: required to establish causation
How well have EV been controlled.
Trade off between internal and external
-steps to increase internal may decrease external
Increase internal but external will suffer
3 criteria for causation
Covariance: variables associated
Temporal precedence: manipulate A before measuring B
Internal validity: eliminated possible alt. Causal explanations by controlling EV