Causal Inference and Policy Recommendations in Physics Education Research.

Sound policy recommendations require valid estimates of causal effects, but observational studies in physics education research often have undefined or loosely specified causal hypotheses. The connections between the observational data and the explicit or implicit causal conclusions are often misstated. The link between the causal conclusions and the policy recommendations is also often loose. Several papers, mostly from Physical Review Physics Education Research, are used to illustrate these issues.