Mini-Essay: 'Spam in a can' and Spaced Repetition Software

In 1970, the harrowing almost-fiasco that was Apollo 13 promoted the astronaut's status from being a passive payload to the active role of an expert again external link. Four days of Type III fun external link in which the crew hot-wired the landing module to provide primary life support made it impossible for anyone to think of them as just spam in a can external link anymore. The idea of the perfect software design died, and human-in-the-loop external link became the default.


There is a phenomenon to be found in almost any spaced repetition software's community: The drive to empower and encourage users to fiddle with all kinds of input parameters of the respective algorithms. Examples truly abound. The Anki Subreddit external link features extensive discussions about the settings in Anki's similarly extensive Deck Options menu. Supermemo has a whole FAQ just about the intricate balancing act of setting the forgetting index external link. Ebisu even requires you to set some fairly abstract initial model parameters (α, β, t) external link.

I used to view all of these as flaws — after all, the second thing SR communities are obsessed with is finding the optimal SR algo external link external link, and if humans are truly bad at anything, it's numerical intuition. From this angle, every degree of freedom set by a human instead of optimized by a machine is a waste, a sign of hubris — or just technology being not quite there.

However, just maybe, some of these manual inputs fulfill a purpose other than filling the gaps the algorithm has left. From a cynical marketing perspective, it's just the IKEA Effect external link, but perhaps it truly is a step towards truly personal software external link₁₀, an acknowledge of the Substitution Myth external link₁₁, an embodiment of the idea that humans are more than spam in a can, even if they are just practicing for an exam.

I still want to have a better tool for calculating the ideal introduction rate for new learning items than external linkfriendly Redditor's guesstimates, though.

This is a external linkMini-Essay in the spirit of external linklearning in public. Feedback is truly welcome. Until next time!