Suppose there are no significant differences ... It would be wrong to assume that you learned that tablets (or books) do not improve learning. What you have shown is that that particular tablet, with that particular software, used in that particular pedagogical strategy, and teaching those particular concepts did not make a difference.
...the [Randomised Control Trial] movement has had an impact equivalent to putting auditors in charge of the R&D department[via Danny Yee's blog]
Additionally, this phrasing reminded me of a story I heard many years ago, about the impossibility of proving a negative:
Have we proven that reindeer cannot fly? No, of course not. We have only shown that on this occasion, under these conditions of atmospheric pressure, temperature, radiation, at this position geographically, at this season, that these 1000 reindeer either could not or chose not to fly.The or chose not to cracks me up.
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