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Spaced repetition can allow for infinite recall

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Re: Spaced repetition can allow for infinite recall

#21

Post by kazinator »

It's cute math, but doesn't take into account the inexplicable differences between the retention of seemingly similar facts. Some items stick very well, whereas others suffer from lapses.

In my Ankid ecks, I have items that have 10+ year intervals. And some, which were introduced at around the same time as those, which have intervals in months, beaten down by lapses.

Anyone who thinks that some simple math leads to infinite recall has not suddenly lapsed on a card whose interval had reached 7 years.

Re: Spaced repetition can allow for infinite recall

#22

Post by kazinator »

dls2016 wrote: post #17

I was anti-memorization until I went back to graduate school for mathematics. I had forgotten (or never learned) a lot of things needed to pass qualifying exams. At some point I ran across the spaced repetition idea (maybe from the Wired SuperMemo article [0]) and I gave it a try. I ended up using it to memorize large portions of baby Rudin and Munkres' Topology, as well as some algebra and a bunch of qualifying exam…

I remember the exact point in my life when I realized how much difference rote memorization makes.

I had the opportunity to write some MC68000 assembly code, at a time which was not too long after having written a complete emulator for it in C. Writing the emulator required me becoming familiar with every single instruction in all of its nuances, and exactly what they all do.

So, having that behind me, I sat down to write this code and it was like wow ... I could just spew the code without having to look anything up. It was so easy!

Re: Spaced repetition can allow for infinite recall

#23

Post by kazinator »

monktastic1 wrote: post #20
kelseyfrog wrote: post #7

This is false if memory's are stored physically in the brain. Unless there is an increase in brain volume, this process will eventually hit the Bekenstein bound. I don't care if the upper bound is "effectively infinite," that's not what the proof claimed.

Proofs rely on assumptions. In this case, they state outright: > We first posit that the number of days T that a fact can be retained before it needs to be reviewed grows as a power-law in s, the number of times it’s been reviewed so far, ... Obviously this assumption will be false in our physical universe, but that doesn't make the proof itself invalid (edited).

In logic, the soundness of a proof in fact has to do with its interpretation in some universe of discourse. To be sound, the argument has to be deductively valid, and its premises have to have true interpretations in the chosen world where it is applied.

Here we have a valid mathematical argument which is unsound in this world, where its assumptions do not hold up.

Re: Spaced repetition can allow for infinite recall

#24

Post by [deleted] »

marcodiego wrote: post #15
kelseyfrog wrote: post #7

This is false if memory's are stored physically in the brain. Unless there is an increase in brain volume, this process will eventually hit the Bekenstein bound. I don't care if the upper bound is "effectively infinite," that's not what the proof claimed.

> "effectively infinite," This is what I have been thinking. If whatever you can remember is bigger than all experiences and lessons you could remember, then your memory is effectively infinite. I don't know if having a continuous effectively infinite memory is good or bad. As someone who play the classical guitar, having a better memory would do wonders for me.

[deleted]

Re: Spaced repetition can allow for infinite recall

#25

Post by xkfm »

dls2016 wrote: post #17

I was anti-memorization until I went back to graduate school for mathematics. I had forgotten (or never learned) a lot of things needed to pass qualifying exams. At some point I ran across the spaced repetition idea (maybe from the Wired SuperMemo article [0]) and I gave it a try. I ended up using it to memorize large portions of baby Rudin and Munkres' Topology, as well as some algebra and a bunch of qualifying exam…

That Supermemo article in Wired hooked me. I still remember where I was when I read it and the feeling of reading it. I still use Supermemo daily, and it's one of the programs keeping on Windows. Anki (and every other SRS program I've tried) just doesn't compare as soon as you move beyond a list of flashcards.

That said, having used Supermemo for over a decade at this point, the hardest thing about SRS is deciding what's actually worth reviewing for a long period of time. I delete (really remove from repetitions) cards from my collection almost on a daily basis.

There's a lot of stuff that seems really important that I just didn't care about after even three months.

Supermemo's incremental reading basically lets you schedule chunks of text or images (alleged video too) like a flashcard from Anki. So, instead of bookmarking articles and never reading them, I can put them into Supermemo and know I'll eventually review it.

It basically counts as a separate type of flashcard, but all your reviews are mixed by default. So on a typical day, I'll have maybe 20 flashcards to review, and then another 10-20 articles.

Supermemo saves where you last were reading, so when I get bored of an article, I just hit next and go to the next one. Eventually, you'll process an article down to individual flashcards like you'd put in Anki, or remove it from your review process altogether. Also, you can just leave the entire article in there if you like rereading it.

Re: Spaced repetition can allow for infinite recall

#26

Post by barking_biscuit »

I mean sure. The trouble is in order to keep the review time per day fixed you need to vary the rate at which you introduce new facts, and as time goes on the interval between when you can afford to introduce new facts will grow to be infinite.

The model also doesn't account for how you feel about doing this activity. This includes the pain of not doing reviews for several days and then having to catch up. The probability you eventually throw in the towel is also a function of how useful you're finding the activity, which in this case since we've opted to keep the per-day study time as fixed will likely be when the interval that you are required to wait before you can add a new fact becomes so large you are routinely bothered by occurrences where you encounter a fact you wanted to put into your SRS but didn't have the bandwidth to.

Source: input 35 new vocab a day into Anki while learning Japanese a decade ago and grew my vocab deck to 18000+ cards. Reviews would take several hours a day, and at one point I stopped adding new words to try and wait for the daily review load to go down. When it never did despite this, I just deleted the entire thing and say fuck it.

Re: Spaced repetition can allow for infinite recall

#27

Post by kelseyfrog »

vntok wrote: post #16
kelseyfrog wrote: post #7

This is false if memory's are stored physically in the brain. Unless there is an increase in brain volume, this process will eventually hit the Bekenstein bound. I don't care if the upper bound is "effectively infinite," that's not what the proof claimed.

> I don't care if the upper bound is "effectively infinite," that's not what the proof claimed. Very interesting. Do you typically process all claims as literally as you just did for this one, notably when you're interacting with people outside of the Internet? In which case, do most people react positively to your behaviour, or do they get annoyed because "you know what I meant"?

Internet "well actually," culture made me this way. I preempt rebuttals I'm not interested in.

Re: Spaced repetition can allow for infinite recall

#28

Post by monktastic1 »

kazinator wrote: post #23
monktastic1 wrote: post #20

Earlier quoted context omitted.

Proofs rely on assumptions. In this case, they state outright: > We first posit that the number of days T that a fact can be retained before it needs to be reviewed grows as a power-law in s, the number of times it’s been reviewed so far, ... Obviously this assumption will be false in our physical universe, but that doesn't make the proof itself invalid (edited).

In logic, the soundness of a proof in fact has to do with its interpretation in some universe of discourse. To be sound, the argument has to be deductively valid, and its premises have to have true interpretations in the chosen world where it is applied. Here we have a valid mathematical argument which is unsound in this world, where its assumptions do not hold up.

You're right. I should have said invalid rather than unsound. I still don't see the point of the criticism, however. Lots of interesting things can be learned by starting from approximations to actual reality.

Re: Spaced repetition can allow for infinite recall

#29

Post by snowpiercer »

dls2016 wrote: post #17

I was anti-memorization until I went back to graduate school for mathematics. I had forgotten (or never learned) a lot of things needed to pass qualifying exams. At some point I ran across the spaced repetition idea (maybe from the Wired SuperMemo article [0]) and I gave it a try. I ended up using it to memorize large portions of baby Rudin and Munkres' Topology, as well as some algebra and a bunch of qualifying exam…

Don't you think you actually did well in your exams because you really understood it and not because you blindly memorized it ?

Re: Spaced repetition can allow for infinite recall

#30

Post by nomel »

snowpiercer wrote: post #29
dls2016 wrote: post #17

I was anti-memorization until I went back to graduate school for mathematics. I had forgotten (or never learned) a lot of things needed to pass qualifying exams. At some point I ran across the spaced repetition idea (maybe from the Wired SuperMemo article [0]) and I gave it a try. I ended up using it to memorize large portions of baby Rudin and Munkres' Topology, as well as some algebra and a bunch of qualifying exam…

Don't you think you actually did well in your exams because you really understood it and not because you blindly memorized it ?

I imagine it's possible that they are related. In my life, I've only witnessed it as a required for being an expert at any topic: experience and memorized knowledge, of a topic.
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