PSYC 217 Lecture Notes - Lecture 14: Time Series, Random Assignment, Internal Validity
Document Summary
Explain why true experiments have higher internal validity than alternative designs. Compare and contrast the basic features of various alternative designs and understand how these features make them more and less susceptible to threats to internal validity. Evaluate scenarios when a specific alternative design would be most appropriate. Recognize and explain how the 5 threats to internal validity operate in various alternative designs. Continuum - internal validity varies across a continuum from low internal validity to high internal validity low internal validity has no causal claim, whereas high internal validity has a strong causal claim. Causal claim takes the form as x causes y , where x is cause and. Components of causal relationships y is effect. Temporal precedence (i. e. , a causes b) process of establishing that whatever the cause is, it did happen before the effect. Control (i. e. , no confounds, control group, random assignment) Ex. one group post-test only interrupted time series.
