Archive for June 20th, 2008

Wired has an excellent article on an optimal memorization algorithm developed by Piotr Wozniak. The technique has been embodied in a software program called SuperMemo and an open-source alternative called Mnemosyne

I’m somewhat skeptical that spending more time on memorizing facts is that useful but given that a few months ago I could barely remember the equation for the roots of a quadratic perhaps I should be more open-minded.

The algorithm is straightforward:

1. Split the knowledge into smallest possible items.
2. With all items associate an E-Factor equal to 2.5.
3. Repeat items using the following intervals:
   I(1):=1
   I(2):=6
   for n>2: I(n):=I(n-1)*EF
   where:
   I(n) – inter-repetition interval after the n-th repetition (in days),
   EF – E-Factor of a given item
   If interval is a fraction, round it up to the nearest integer.
4. After each repetition assess the quality of repetition response in 0-5 grade scale:
   5 – perfect response
   4 – correct response after a hesitation
   3 – correct response recalled with serious difficulty
   2 – incorrect response; where the correct one seemed easy to recall
   1 – incorrect response; the correct one remembered
   0 – complete blackout.
5. After each repetition modify the E-Factor of the recently repeated item according to the formula:
   EF’:=EF+(0.1-(5-q)*(0.08+(5-q)*0.02))
   where:
   EF’ – new value of the E-Factor,
   EF – old value of the E-Factor,
   q – quality of the response in the 0-5 grade scale.
   If EF is less than 1.3 then let EF be 1.3.
6. If the quality response was lower than 3 then start repetitions for the item from the beginning without changing the E-Factor (i.e. use intervals I(1), I(2) etc. as if the item was memorized anew).
7. After each repetition session of a given day repeat again all items that scored below four in the quality assessment. Continue the repetitions until all of these items score at least four.

There is a website called Memverse which has implemented this algorithm for memorizing popular bible verses. I’ve been using the site for about 3 months now and it is very impressive how much you can retain using the algorithm.