Unfortunately there's no single good source for this; 30% is just an approximate aggregate figure I've come up with after seeing various people's posts on diffe

Unfortunately there's no single good source for this; 30% is just an approximate aggregate figure I've come up with after seeing various people's posts on different sites. Some things I could find just now: Anki vs. SM-8: https://anki.tenderapp.com/discussions/effective-learning/1258-sm-2-vs-sm-15/page/2?full_site=1 https://anki.tenderapp.com/discussions/effective-learning/12... SM-2 vs. SM-17: https://supermemo.guru/wiki/Universal_metric_for_cross-comparison_of_spaced_repetition_algorithms https://supermemo.guru/wiki/Universal_metric_for_cross-compa... Anki vs. custom machine learning scheduler: https://old.reddit.com/r/Anki/comments/d0i8uy/improved_algorithm_for_anki_scheduling_w/ https://old.reddit.com/r/Anki/comments/d0i8uy/improved_algor... Anki vs SM-17: https://unrelatedwaffle.medium.com/battle-of-the-spaced-repetition-heavyweights-anki-vs-supermemo-part-ii-10ef2cd0379d https://unrelatedwaffle.medium.com/battle-of-the-spaced-repe... SuperMemo seems to fall behind Anki in the short term (<6 months), but eventually makes up for it. Some of the links reflect that. As for open-source implementations, there this: https://github.com/slaypni/SM-15 https://github.com/slaypni/SM-15