This is not about solving homework questions per-se. Several questions of the type "How do I solve for this probability density" can be solved by the Jacobian method (change of variables) but most answers even the ones most voted usually just present a particular solution that addresses only the question at hand. Whenever I assign homework with such questions my intent was always for students to learn the general method. In sum: here should we give them fish or should we teach them how to fish?

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    $\begingroup$ Learning how to fish starts with catching one fish at a time. Sometimes a student needs to solve a few concrete examples to build up to the general case. $\endgroup$
    – Alexander Gruber Mod
    Nov 14, 2013 at 3:49
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    $\begingroup$ In teaching, I have often deliberately withheld some general formulas for a while, so that students can acquire concrete experience. Usually doesn't work. For example, even if I do not mention it for a while, they quickly find out about Bayes' Rule, and use it to get wrong answers. $\endgroup$ Nov 14, 2013 at 4:12
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    $\begingroup$ You mean, something like this or this? $\endgroup$
    – Did
    Nov 14, 2013 at 6:09
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    $\begingroup$ This is ostensibly a place to learn about fishing. We should teach people to fish. We may even want to guide people who want fish to realize that they want to learn to fish. People who just want a fish should visit a fishmonger. (and fishmongers should monger fish in a suitable market rather than in the halls of learning) $\endgroup$
    – user14972
    Nov 15, 2013 at 12:49
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    $\begingroup$ @André: ... and use it to get wrong answers. Ain’t it the truth! $\endgroup$ Nov 18, 2013 at 6:42

1 Answer 1


One possibility is to either answer one such question in full generality or ask-and-answer yourself one such question, and then tagging it with and adding the question to this list. After which you can always refer to that item when you see another such question where the general technique applies.

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    $\begingroup$ +1. This is one of the situations where answering your own question can make sense - because it gives you a chance to ask what you wish the askers would have asked, so that you can actually say the answer on the tip of your tongue. The thing that makes this type of self-answer good, in my opinion, is that it responds to a need that you have seen already, and you will be able to use the answer you write as a reference for other answers. So it is not just you talking to yourself about how to compute densities - that would be better on a personal website. $\endgroup$ Nov 14, 2013 at 12:54
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    $\begingroup$ -1. Such canned answers are frequently less than helpful to real students, as distinct from idealized students. $\endgroup$ Nov 18, 2013 at 6:43

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