Bradford S. Bell and Jessica E. Federman write,

The meta-analyses reviewed above show that when instructional design characteristics are held constant across delivery conditions, e-learning and classroom instruction generally produce similar learning outcomes.

Pointer from Timothy Taylor–read his whole post.

The null hypothesis is that there is no difference in outcomes, and apparently the “meta analysis” does not reject the null hypothesis. Taylor interprets this as evidence that online learning has “caught up” to classroom learning in terms of quality. My more cynical interpretation is that there was never any catching up required, because what students learn does not appear to depend in any way on how they are taught. I am sure that there is a limit to this: presumably, if you do a randomized experiment in which one group of students gets $50,000 worth of instruction and another group gets zero, you will see some difference in outcomes. However, I would bet that, relative to what we do today, the way to improve cost-effectiveness in education is to slash costs. That is, my view of the null hypothesis is that most of what we spend on education has no marginal impact.

Note, however, that the authors of the study seem convinced that the null hypothesis is false. They believe that empirical evidence shows that pedagogical techniques do affect outcomes.