Controlling Confounds in a Posttest Only Nonequivalent Groups Design
To enhance the internal validity of a posttest only nonequivalent groups design, researchers can intentionally select comparison groups that share key characteristics. For instance, when evaluating a teaching method across two classrooms, a researcher might select classes within the same school that have similar baseline test scores and teachers with comparable styles to eliminate major confounds. However, because true random assignment is absent, unmeasured confounding variables may still influence the outcomes, meaning researchers cannot make definitive causal claims.
0
1
Tags
KPU
Research Methods in Psychology - 4th American Edition @ KPU
Related
Example of a Posttest Only Nonequivalent Groups Design
Pretest-Posttest Nonequivalent Groups Design
Controlling Confounds in a Posttest Only Nonequivalent Groups Design
Which of the following best describes a posttest only nonequivalent groups design?
Controlling Confounds in a Posttest Only Nonequivalent Groups Design
A researcher wants to test a new fraction-teaching strategy. She implements it in one third-grade classroom and compares those students' final math scores to another classroom that used traditional methods. Students were not randomly assigned to these classrooms. What is the primary reason this design cannot establish that the teaching strategy caused any observed difference in scores?
Learn After
In a posttest only nonequivalent groups design, why are researchers unable to make definitive causal claims even if they carefully select comparison groups that share key characteristics?
In a posttest only nonequivalent groups design, selecting comparison groups that share key characteristics guarantees the elimination of all confounding variables.