One conclusion you might reach hint after completing the rea

One conclusion you might reach (hint) after completing the readings for this assignment is that there are no bad designs, only bad design choices (and implementations). State a research question for which a single-group post-test only design can yield relatively unambiguous findings.

Solution

Quasi-experimental design has a number of advantages over the single-group pretest-posttest design. In addition to eliminating some threats to internal validity found in the one-group pretest-posttest design, the time series design provides measures of how long a treatment effect will occur.Tthe regression-discontinuity design often allows researchers to make relatively unambiguous interpretation of treatment effects, even where groups are not initially equivalent. Indeed, evidence indicates that this design, when properly implemented, is equivalent to a randomized experiment in its ability to rule out threats to internal validity.