## Posts

Comment by anneominous on Why the tails come apart · 2014-10-17T21:30:31.573Z · score: 0 (0 votes) · LW · GW

A better way would be to make the criticisms more concrete.

What isn't "concrete" about it? I think the whole article is an exercise in stating the obvious, to those who have had basic education in statistics. Stricter correlations tend to be more linear. A broader spectrum of data points is pretty much by definition "fatter". I don't see how this is actually very instructive. And to be honest, I don't see how I could be much more specific.

Where, and what did they say? We cannot know what better resources you know of unless you tell us.

You mean you've never had a statistics class? Honestly? I'm not trying to be snide, just asking.

Extreme data points are often called "outliers" for a reason. Since (again, almost -- but not quite -- by definition, it depends on circumstances) they do not generally show as strong a correlation, "other factors may weigh more". This is a not a revelation. I don't disagree with it, I'm simply saying it's rather elementary logic.

Which brings us back to the main point I was making: I did not feel this was particularly instructive.

Besides, you're talking there about something you previously called "just wrong".

Wrong in the sense that I don't see any actual demonstrated relationship between his ellipses and the data, except for simple, rather intuitive observation. It's merely an illustrative tool. More specifically:

So this offers an explanation why divergence at the tails is ubiquitous. Providing the sample size is largeish, and the correlation not to tight (the tighter the correlation, the larger the sample size required), one will observe the ellipses with the bulging sides of the distribution (2).

This is an incorrect statement. What he is offering is a way to describe how data at the extreme ends may vary from correlation. Not "why". There is nothing here establishing causation.

If we are to be "less wrong", then we should endeavor to not make confused comments like that.

Comment by anneominous on Why the tails come apart · 2014-09-17T04:56:53.205Z · score: 0 (0 votes) · LW · GW

"At the extremes, other factors may weigh more."

Nothing that hasn't been said before, and in my opinion better.

I don't particularly like your "ellipse" generalization, either, because it's just wrong. We already know a perfect correlation would be linear. We already know a lesser correlation is "fatter". Bringing ellipses into the issue is just an intuitive, illustrative fiction, which I really don't appreciate very much because it's not particularly informative and it isn't scientifically sound at all.

Please don't misunderstand me: I do think it is illustrative, and I do think it has its place. In the newby section maybe.

Understand, I am aware that may come across as overly harsh, but it isn't meant that way. I'm not trying to be impolite. It's just my opinion and I honestly don't know a better way to express it right now without being dishonest.

Comment by anneominous on Rationality Quotes September 2014 · 2014-09-17T04:27:57.076Z · score: -1 (1 votes) · LW · GW

Quote: "The third perhaps is especially tricky. If you "re-express your target’s position ... clearly" you remove the obfuscation that concealed the gap. Now what? Leaving the gap in clear view creates a strawman. Attempting to fill it draws a certain amount of attention to it; you certainly fail the ideological Turing test because you are making arguments that you opponents don't make."

Just no. An argument is an argument. It is complete or not. If there is a gap in the argument, in most cases there are two eventualities: (a) the leap is a true one assuming what others would find obvious, or (b) either an honest error in the argument or an attempt to cover up a flaw in the argument.

If there is a way to "fill in" the argument that is the only way it could be filled in, you are justified in doing so, while pointing out that you are doing so. If either of the (b) cases hold, however, you must still point them out, in order to maintain your own credibility. Especially if you are refuting an argument, the gap should be addressed and not glossed over.

You might treat the (b) situations differently, perhaps politely pointing out that the original author made an error there, or perhaps not-so-politely pointing out that something is amiss. But you still address the issue. If you do not, the onus is now on you, because you have then "adopted" that incomplete or erroneous argument.

For example: your own example argument has a rather huge and glaring hole in it: "bad-use will increase a lot and good-use will increase a little". However, history and modern examples both show this to be false: in the real world, decriminalization has increased bad-use only slightly if at all, and good-use more. (See the paper "The Portugal Experiment" for one good example.)

Was there any problem there with my treatment of this rather gaping "gap" in your argument?