Threats to Internal Validity

history threat

occurs when an event (pos/neg) outside the experiment threatens internal validity by changing the dependent variable

history threat

occurs before testing session

simultaneous testing

history threat is solved by _________

maturation threat

produced when phys or psych changes in subj threaten internal validity by changing DV

control group

maturation threat is solved by __________

testing threat

occurs when prior exposure to a measurement procedure affects performance on this measure during the experiment

testing threat

performance tends to improve somewhat with practice even without any special treatment

control group

testing threat is solved by __________

testing threat

questionnaire is a threat

testing threat

the reason why pilot testers can't participate in the actual research

instrumentation threat

when changes in the measurement instrument or measuring procedure threatens internal validity

instrumentation threat

fault of the researcher

statistical regression

occurs when subjects are assigned to conditions on the basis of extreme scores

statistical regression

extreme scores typically get closer to the mean even without any treatment

large sample size

statistical regression can be solved by ___________

selection threat

occurs when individual differences are not balanced across treatment conditions by the assignment procedure

random assignment

selection threat can be solved by ______________

subject mortality threat

occurs when subjs drop out of experimental conditions at diff rates

subject mortality threat

occurs when there are more participants that drop out than those that stayed

selection interaction

occurs when a selection threat combines with at least one other threat

selection interaction

multiple threats occurred