Confirmed again: high quality and #openaccess  go hand in hand. Open textbooks…

"Open textbooks can be just as good (rigorous and effective) as the best non-OA textbooks. Here's a new study confirming it.

We already knew that OA journals can be just as good as the best non-OA journals. But on both fronts (textbooks and journals) there are doubters. Moreover, there are wretched examples of OA textbooks and OA journals, which some mistake (innocently or cynically) for representative examples. So bring on the empirical studies!

Nobody thinks the worst subscription journals are representative of their class, let alone the best specimens of their class. So why do so many people -- so many academics who ought to care about evidence -- make this mistake with OA journals and OA textbooks? I have charitable and uncharitable answers to this question. But here's my charitable answer. Subscription journals have been around long enough for us to discriminate. But we had to learn to discriminate. Undergraduates and young graduate students often think all journals are equivalent in quality and differ only in topic or methodological orientation. But if they stay in the field, they start to see quality differences as well. Many academics are still at the bottom of this learning curve for OA journals and OA textbooks, or their experience is limited to the bottom tiers of quality and doesn't yet extend to the top tiers of quality."