Recommendations for practice are routinely included in articles that report educational research. Robinson et al. suggest that reports of primary research should not routinely do so. They argue that single primary research studies seldom have sufficient external validity to support claims about practice policy. In this article, I draw on recent statistical research that has formalized subjective notions about generalizability from experiments. I show that even rather large experiments often do not support generalizations to policy-relevant inference populations. This suggests that single primary studies are unlikely to be sufficiently generalizable to support recommendations for practice.
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This paper is based in part on work supported by the US National Science Foundation (NSF) under grants #0815295 and #1118978. Any opinions, findings, and conclusions or recommendations are those of the authors and do not necessarily represent the views of the NSF.
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Hedges, L.V. Recommendations for Practice: Justifying Claims of Generalizability. Educ Psychol Rev 25, 331–337 (2013). https://doi.org/10.1007/s10648-013-9239-x
- Practice policy