Wednesday, July 21, 2010

Memorizing with Smart Flashcards: the Freakish Power of Anki

Memorizing is my achilles heel. I think avoiding memorization even
shaped the course of my life, away from things requiring that kind of
factual knowledge and towards things that mostly require understanding
systems. I shuddered when I heard the stories from my friends in medical
school about being examined on the names of hundreds of bones - I felt
like I just couldn't do it. But now I have a tool that I think could
achieve that for my brain, called Anki. It's technically a spaced
memorization program, derived from the original called Supermemo. But
Anki is free and has a *much* less complicated interface, while still
having tons of great features, including the ability to sync over the
internet (it is also open source and has good import & export
capabilities so that you're not locked in).

The best intro is probably via the youtube videos on the website where you can also download it:

http://ichi2.net/anki/
But I will try to describe it here. Anki is essentially smart flash
cards. It's good for learning any kind of knowledge that can be
summarized as a short answer or fill-in-the-blank. You input the front
and back of a lot of these "cards" (can be imported from a simple
spreadsheet), and then Anki gives them to you at exponential intervals:
say every day for a couple of days, and then 3 days later, 7 days later,
21 days later, 2 months later etc, to infinity and beyond. The interval
is modified by whether you got it right (and how hard it was) or wrong:
it presents you with the front of the card, you try to think the answer
to yourself, then press the spacebar to reveal the back, and click or
press a key to say whether you got it. If you get it wrong, you get it
again after the day's normal review, and then probably tomorrow too. The
theory is that if you get reminded just before the point when you would
naturally forget it, then you can retain knowledge indefinitely. And
pretty much an unlimited amount.

That's assuming you actually Anki every day, and I was wondering if I'd
be able to keep it up. Turns out I didn't need to worry: it's something
I look *forward* to, even procrastinate on things with. For the number
of cards I have it only takes 6-10 minutes to do, and it's very
satisfying to see how quickly progress comes at mastering these facts. I
started 40 days ago by adding a few different sets of facts just to try
it out and because I wanted to have them in my brain (plus most of these
were already in a format that was easy to enter): metric conversions,
the International Phonetic Alphabet, constellation names, the greek
alphabet, some numbers to do with vision science and facts about 19th
century vision scientists, and some constants and timelines that I
wanted to use as reference markers. In total 450 cards, which are added
to my study schedule 10 per day, so that I've almost seen all of them now.

How are the results? Well the wealth of stats and graphs that Anki
provides to warm my nerdy soul give some hard evidence: when I first see
cards I get them 57% correct (remember that I already read these facts,
in order to enter them). However my average success rate for non
first-time cards - most of which I've seen a bunch of times now - is
87%. That's a more than 50% improvement! And it's still relatively early
for these facts. I feel like I can easily get to point of answering them
95% correctly, and with every one occasionally turning up months and
years from now, keep that rate. What about subjectively? Knowing these
facts with so little effort feels a little freaky. Like Neo getting kung
fu uploaded into his brain, or the subliminal training in Brave New
World. Without checking: The sun is 150 million km from the earth. One
teaspoon is about 5 ml. The big bang was 14 billion years ago. The peak
response for the short, medium and long wavelength cones are 430, 540
and 570. Despite what people assume, except when it comes to movie
character actors and 1950s science fiction I've never been a fact and
trivia guy. It's a new feeling to get enjoyment just running through my
command of these numbers in my mind.

Some things are proving tricky to shove into my brain even using this
method, and I'm finding it useful to go back to this great document from
the somewhat crankish creator of supermemo:
http://www.supermemo.com/articles/20rules.htm
Essentially the important points are to understand before you memorize,
try to break things into the simplest possible chunks, and avoid
learning lists. How I wish I'd had this in school! So many classes could
have been a piece of cake, because their knowledge was susceptible to
being formulated as fill-in-the-blanks. And I might have actually
retained the knowledge (ever heard someone say, "I'm just going to
forget all this right after the exam"?). Further advice for those tough
cards (and the beautiful part is that they identify themselves, since
they keep coming up while the easy ones are cast far into the future) is
that spaced memorization works *great* with mnemonics. For example the
star Mirphak was giving me a lot of trouble, and coming up every day,
until I made up the mnemonic that Perseus (the constellation it's in)
used a MIRror to PHAK up medusa. Bam, now I'm acing that card. I also
put a reminder of the mnemonic on the back of the card, easy to do even
in the middle of reviewing.

You might be questioning at this point how far memorization can take
you. Is it the same as real knowledge? It's definitely not the whole
story, but I've come to believe that it goes hand in hand with
understanding. Even with my somewhat silly starting set I'm already
seeing how having facts at my fingertips can help me make connections
and inferences. For instance when I was on the plane and saw how far
we'd flown on the way to amsterdam, I automatically compared it to the
circumference of the earth (40,000 km). When a book referenced
creationists denying that dinosaurs existed 65 million years ago, I
realized that that's around the time when they went extinct. And more
substantially, remembering the active periods of a few different vision
scientists made me make all kinds of comparisons of who came first and
who were contemporaries when I was reading a bit more about them. Even
though all these facts are accessible within seconds on the internet,
there is something incredibly powerful about having them all in your
head at once. I think it's a foundation for creativity and true depth of
knowledge. I have big ambitions for using it to memorize hundreds of key
concepts in my field, not to mention references I might be asked about
in my PhD defence. And because it's so easy to use, there's no reason
not to boot up Anki at a moment's notice and add anything you want to
remember, including facts from something you're reading (especially
useful for mass anki-fying: the "cloze" feature)

Give it a try, and then tell me what you've got in your deck!