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Comment author: atorm 07 October 2011 06:00:47PM 7 points [-]

A friend of mine claims Fahrenheit is more convenient because of "-ties". "Today it will be in the fifties/sixties/thirties/high seventies." Celsius doesn't have conveniently-spoken ranges that give users a general idea of the weather. I countered with high and low teens, low twenties, but I don't think his point is completely invalid.

You say centimeters are better for small things and meters better for large things, but neither are very useful for things that might constitute an arm-load. I'm not sure that sentence is very clear, so I'll try examples. My laptop is 36 centimeters wide, which is an inconveniently large number of units for it to be, but it's only a little more than a foot. This textbook: about a foot square. That hard-drive is half a foot (I'll admit that "six inches" was easier to the tongue, but in reality it's closer to seven, which I wouldn't say). What I'm trying to say is that the unit "foot" is very convenient for things that we might be handling in everyday situations, unless those things are hand-sized.

Comment author: MatthewW 03 November 2011 06:59:30PM 2 points [-]

More generally, the words for the non-metric units are often much more convenient than the words for the metric ones. I think this effect is much stronger than any difference in convenience of the actual sizes of the units.

I think it's the main reason why many of the the non-metric units are still more popular for everyday use than the metric ones in the UK, even though we've all learned metric at school for the last forty years or so.

Comment author: dlthomas 28 October 2011 10:16:15PM 0 points [-]

What's wrong with that?

Comment author: MatthewW 29 October 2011 11:34:59AM 0 points [-]

It's slightly disconcerting to imagine some of the writing coming from the pen of an Anglican deacon.

Comment author: Vladimir_M 06 September 2011 11:28:33PM *  5 points [-]

I see at least three problems with your criticism:

  1. Orwell doesn't provide any useful guidelines on when the exceptions to his rules should apply. He only says you shouldn't use them when it would make you sound "outright barbarous." But this makes these rules useless as advice, since the exceptions are supposed to be guided by aesthetic feeling -- and those whose feeling is refined enough ipso facto already know what to do even without Orwell.

  2. The second LL article cites a result that the use of passives in Orwell's essay is in fact well above the average found in a large sample of English prose. So whatever exeptions to his rules he has in mind, this necesarily implies that he breaks his own advice. There is no reasonable interpretaton of his admonition to avoid passives, whatever caveats and exceptions are attached to it, that would permit writing a whole essay with such an exceptionally high rate of passives.

  3. One sample of old text is very weak evidence of the average quality of old writing. Especially considering that it's from a highly non-representative source. (By which I mean a high-budget collaborative translation by top-rate English stylists, which has also survived popularity competition with other Biblical translations.)

Comment author: MatthewW 28 October 2011 10:41:07PM 2 points [-]

The useful advice is in the first 5000 words of the essay, most importantly in the examples of bad writing. The 100 words or so of 'rules' are just a summary at the end.

This kind of teaching is common in other subjects. For example, in a Go textbook it's not rare to see a chapter containing a number of examples and a purported 'rule' to cover them, where the rule as stated is broken all the time in professional play. It would be a mistake to conclude that the author isn't a strong player, or that the chapter doesn't contain helpful advice. The 'rule' is just a way to describe a group of related examples.

I think it's better to think of the 'rules' in Orwell's essay more like mnemonics for what he's said earlier, rather than instructions to be followed on their own.

Comment author: lythrum 27 October 2011 09:05:59PM 1 point [-]

I strongly agree. I find Eliezer's italics so off-putting that I avoid reading his writing in formatted text. I don't know why, and I'm sure not everyone has the same reaction, but excess italics just make me twitch.

Comment author: MatthewW 28 October 2011 09:57:50PM 0 points [-]

I don't find it off-putting, but it does make me feel I'm reading Lewis Carrol.

Comment author: tut 11 October 2011 05:43:33PM 0 points [-]

No statistics at all.

Or to be a bit more precise: If you have good enough data to do anything useful with frequentist methods then you may use bayesian reasoning as well. What the judge forbade is using bayes to sound scientific when you can't back up your priors.

Comment author: MatthewW 16 October 2011 09:04:08PM 1 point [-]

Priors don't come into it. The expert was presenting likelihood ratios directly (though in an obscure form of words).

Comment author: Eliezer_Yudkowsky 07 October 2011 07:56:35PM 4 points [-]

I have some sympathy for the judge here, even as I wince. If in real life juries don't understand Bayes and the actual effect of its use in court is to be grossly misused or make wild guesses sound formal and authoritative, then in the end you can't have Bayes's Theorem used formally in courts.

Comment author: MatthewW 16 October 2011 09:02:52PM 0 points [-]

That isn't what was going on in this case. The expert wasn't presenting statistics to the jury (apparently that's already forbidden).

The good news from this case (well, it's news to me) is that the UK forensic science service both understands the statistics and has sensible written procedures for using them, which some of the examiners follow. But they then have to turn the likelihood ratio into a rather unhelpful form of words like 'moderately strong scientific support' (not to be confused with 'moderate scientific support', which is weaker), because bringing the likelihood ratios into court is forbidden.

(Bayes' Theorem itself doesn't really come into this case.)

Comment author: MatthewW 03 October 2011 07:37:46PM 4 points [-]

This isn't quite "a judge has ruled that [Bayes' theorem] can no longer be used", but I don't think it's good.

The judges decided that using a formula to calculate likelihood isn't allowed in cases where the numbers plugged into the formula are themselves uncertain (paragraph 86), and using conservative figures apparently doesn't help.

Paragraph 90 says that it's already established law that Bayes' theorem and likelihood ratios "should not be used", but I think it means "shouldn't be talked about in front of the jury".

Paragraph 91 says explicitly that the court wasn't deciding how (or whether) Bayes' Theorem and likelihood ratios can be used in cases where the numbers plugged into the formula aren't themselves very uncertain.

In paragraph 95, the judges decide that (when matching footprints) it's OK for an expert to stare at the data, come up with a feeling about the strength of the evidence, and express that in words, while it's not OK for the same expert to do a pencil-and-paper calculation and present the result in similar words.

I think part of the point is that when the expert is cross-examined, the jury will react differently if she says "this evidence is strong because I've got lots of experience and it feels strong to me", rather than "this evidence is strong because I looked up all the frequencies and did the appropriate calculation".

I do get the impression that the approach of multiplying likelihood ratios is being treated as a controversial scientific process (as if it were, say, a chemical process that purported to detect blood), and one which is already frowned upon. Eg paras 46, 108 iii).

Comment author: Morendil 03 October 2011 05:34:40PM *  9 points [-]

Don't read just the article, go see also the actual judgment (HT ciphergoth; pdf). I won't say "read it" because it's the kind of thing that may not be worth reading entire, but at least skim it to get a feel for what's actually being argued.

My sense of it is that the judge is saying "stats should not be allowed when the numbers on which they're based are 'merely' quantifying someone's uncertainty, rather than be anointed by scientists". Which is still silly, as it ignores that "scientific" stats do nothing other than quantify uncertainty; but it doesn't say "Ban Bayes".

Comment author: MatthewW 03 October 2011 07:28:22PM 4 points [-]

Thanks for the link.

I think paragraphs 80 to 86 are the key paragraphs.

They're declaring that using a formula isn't allowed in cases where the numbers plugged into the formula are themselves uncertain.

But in this case, where there was uncertainty in the underlying data the expert tried to take a conservative figure. The judges don't seem to think that helps, but they don't say why. In particular, para 108 iv) seems rather wrongheaded for this reason.

(It looks like one of the main reasons they overturned the original judgement was that the arguments in court ended up leaving the jury hearing less conservative estimates of the underlying figures than the ones the expert used (paras 103 and 108). That seems like a poor advertisement for the practice of keeping explicit calculations away from the jury.)

Comment author: GLaDOS 23 July 2011 02:07:06PM *  6 points [-]

I'm not sure the correction is that relevant. The US and the EU together make up about 40% of global GDP (PPP).

Several minor economies with nearly identical conditions and restrictions such as Canada, New Zealand, Australia, South Africa, Norway, Switzerland ... add up to another 3% or so.Most states in Latin America have similar legal prohibitions as well, they are not as well enforced, but avoiding them still imposes costs. This is mentioning nothing of Japan or other developed East Asian economies (though to be fair losses are probably much smaller than the developed West and perhaps even Latin America).

The other half of the world's has a massive opportunity cost due to the mentioned half's described inefficiency. Converting this loss into number of lives or quality of life is a depressing exercise.

Fortunately that is only a problem if you care about humans.

Comment author: MatthewW 27 July 2011 08:06:33PM 3 points [-]

Well, I'm in the UK, and there's no law against using IQ-style tests for job applicants here. Is that really the case in the US? (I assume the "You're a terrorist" bit was hyperbole.)

Employers here still often ask for apparently-irrelevant degrees. But admission to university here isn't noticeably based on 'generic' tests like the SAT; it's mostly done on the grades from subject-specific exams. So I doubt employers are treating the degrees as a proxy for SAT-style testing.

In response to Ability to react
Comment author: MatthewW 18 February 2011 09:19:53PM 1 point [-]

In your third speculation, I think the first and second category have got swapped round.

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