Ex post facto past events – UGC NET Question

Ex post facto research examines relationships between variables after the events or treatments have already occurred, without the researcher manipulating the independent variable. Groups are formed on the basis of existing characteristics, such as gender or prior experience, and the researcher attempts to infer possible causes of observed differences. Because manipulation and random assignment are not possible, it is classified as a non-experimental design. The stem clearly points to this situation, so ex post facto research is the correct answer.

Option A:
Experimental research actively manipulates one or more independent variables and randomly assigns participants to groups, allowing strong causal inferences. In ex post facto studies, such manipulation is not feasible, so experimental is not an accurate term for the design described.

Option B:
Ex post facto studies try to approximate causal explanations by comparing groups that differ on the independent variable that has already occurred, controlling for some extraneous factors statistically if possible. This aligns with the stem’s key feature: the independent variable cannot be manipulated by the researcher.

Option C:
Action research is a practitioner-led cyclic approach (plan–act–observe–reflect) aimed at improving local practice. It involves intentional interventions by the practitioner, unlike ex post facto designs where the “cause” has already occurred and is not manipulated.

Option D:
Longitudinal research studies the same individuals over time to observe change. While it may involve repeated measures, it is defined by time-based follow-up, not specifically by the “already occurred and cannot be manipulated” feature that defines ex post facto research.