You're looking at Less Wrong's discussion board. This includes all posts, including those that haven't been promoted to the front page yet. For more information, see About Less Wrong.

Misha comments on What Direct Instruction is - Less Wrong Discussion

49 [deleted] 04 September 2011 11:03PM

You are viewing a comment permalink. View the original post to see all comments and the full post content.

Article Navigation

Comments (81)
Tags: education

Comments (81)

You are viewing a single comment's thread. Show more comments above.

Comment author: [deleted] 05 September 2011 12:15:24AM *  4 points [-]

The examples don't have to be binary ones, those are just the easiest ones to describe and the most common. If you were teaching addition, your examples would be (more or less) addition problems, but they would still follow the same rules, with some modifications (for instance, negative examples don't really make sense in the context of "2+3=?").

But basically you have the right idea. Another thing I didn't touch on in the above post is that the testing examples seem to serve a teaching role, as well. I've even seen example sequences in which all negative examples are left until the testing, though I haven't read carefully enough to be able to say when one is supposed to do this.

Comment author: atucker 05 September 2011 02:15:23AM *  1 point [-]

But basically you have the right idea. Another thing I didn't touch on in the above post is that the testing examples seem to serve a teaching role, as well.

Ah, yup. Also heard about this effect with spaced repetition.

I've even seen example sequences in which all negative examples are left until the testing, though I haven't read carefully enough to be able to say when one is supposed to do this.

That seems like an interesting case.

Comment author: [deleted] 05 September 2011 02:54:17AM *  3 points [-]

That seems like an interesting case.

Okay, so looking into it further, this sometimes happens when teaching a "noun" concept (that is, a basic concept with multiple defining qualities and possibly a fuzzy boundary). The text has this to say about the matter:

Because very small differences in examples are usually not shown in a noun sequence, the sequence is usually fairly short, consisting of enough positive examples to show the range of variation and those negatives that might be confused with the positives.

There are multiple examples of noun sequences:

  • Learning the concept of a "truck", distinguishing from already-known concepts of "car", "bus", and "train". Three truck examples are given, then testing begins; no negative examples.
  • Learning the letter "b", distinguishing from several already-known letters. Only two examples ("b" in two fonts) are given before the test examples, because the concept has a narrow range; no negative examples.
  • Identifying a "black oak" leaf, distinguishing it from other leaves. A "white oak" leaf is also shown in the test examples, because the two look very similar.
  • Learning the category "vehicle", when various types of vehicles are known. It has negative examples of "swing" and "lawnmower" to demonstrate boundary cases, before the testing examples begin.

Ah, yup. Also heard about this effect with spaced repetition.

I'm surprised I didn't make the connection between Direct Instruction and spaced repetition earlier. A lot of the theory of DI easily translates to making better spaced repetition tests.

Comment author: Viliam_Bur 05 September 2011 09:35:08AM 0 points [-]

Learning the letter "b", distinguishing from several already-known letters. Only two examples ("b" in two fonts) are given before the test examples, because the concept has a narrow range; no negative examples.

I think it would be good to include also non-examples of "d", "p" and "q".

Generally, I think that any explanation should include non-examples, to show the boundaries of the concept. Otherwise you did not disprove the hypothesis that "anything is a valid example".

My intuition about DI is that you give a few examples and non-examples such that an Occam's razor will lead student to the correct explanation. Or in other words, "faultless communication" is one where the correct interpretation of teacher's words has lower (preferably: much lower) Kolmogorov complexity than any incorrect interpretation.

Comment author: [deleted] 05 September 2011 02:47:28PM 0 points [-]

One of the rules for nouns is that the negative examples you use (in the whole sequence, including testing) are ones the learner already knows. In this case, I think that, because there is such a narrow range of variation in letters, they felt like the already-known "d", "p", and "q" could be saved for the test examples.

I personally think it wouldn't hurt to mention them before the testing examples, too, and this seems like something open to interpretation.

Powered by Reddit Powered by Reddit