Archive for October, 2009

Simpson’s Paradox

I suck at weekends. I’ve done nothing useful today. But something earlier reminded me about this, and for lack of anything else worth saying I’m going to talk about maths some more. I say bug humbah to your Hallowe’en malarkey. If you want spooky monsters and candy, go bother someone else. At my house, you get a lecture on algebra.

Simpson’s paradox is one of those really weird quirks of mathematics, which more people could do with understanding. It’s not even enormously complicated – the deep maths behind it can get pretty weird, but it’s really easy to appreciate how bizarrely counter-intuitive this stuff can be.

So, the paradox, and an example lifted straight from Wikipedia.

Some medical research happened a while back, into treatment for kidney stones. They took 700 people, split them into two groups, and tested a different treatment on each group. Treatment A worked on 273 out of 350 people in the first group, a success rate of 78%. Treatment B worked on 289 out of 350, or 83%.

So Treatment B works better, right?

Well, it turns out there are two different types of kidney stones. Broadly speaking, you can divide them into the “small” kind, and the “large” kind. So, even though Treatment B works better overall, maybe Treatment A is better for either small or large ones specifically. Right?

Well, half-right.

In fact, they found that Treatment A worked 93% of the time on small stones, while Treatment B worked 87% of the time. Meanwhile, with large stones, Treatment A hits 73% to Treatment B’s 69%.

So, for small kidney stones, Treatment A works demonstrably better than Treatment B. And for large kidney stones, A is still more successful than B. Treatment A actually works better in both individual cases.

But for kidney stones in general, Treatment B has a better overall success rate.

I’m a pretty intelligent person who studied mathematics more than anything else in life until I was 22, and I still don’t know how the fuck that works.

I mean, I understand all the maths behind it, it just still hurts my head. So now I’m going to go lie down. (This may also be related to the fact that it’s midnight now.)

Read Full Post »

Numbers and lies

Oh god I love this thread at FAIL Blog so much. You’re probably not a maths geek, so it might not mean much to you, but think about how much fun it is when people who don’t quite know what they’re talking about are convinced they do. Then apply that to a field of study in which absolute truth exists, and any answer or way of doing things is either definitely right or definitely wrong.

I know the actual calculus problem isn’t the point of the fail, but since when does that stop me? I solved it after a minute’s scribbling on a post-it, and got it right, because it’s not actually that complicated a question. What was more interesting was figuring out exactly how the over-confident engineering majors near the start of the discussion came up with their wrong answer. And I pretty quickly figured out what they’d done, and it’s quite funny. But only because I’m a real geek.

It’s interesting because they’re doing some moderately high-end maths, beyond the level most people would have studied to, but at the same time the mistakes they’re making indicate a fundamental lack of understanding about how differential calculus works. And that’s a perfectly okay thing to lack – I know a lot of fine, upstanding citizens with no concept of how differential calculus works at all, and I wouldn’t think to count it against them. But they have the sense not to go on internet message boards and try to teach people maths.

Also, I’ve started a new blog, which I’m planning to post to every weekday, as well as this one. It’s mostly a writing exercise for me, but I may start trying to get it noticed a bit too, now that it’s been going a week and I’m fairly sure my interest isn’t going to just fizzle out. It’s called The Daily Half-Truth, and the idea is to write weird and surreal news stories based on actual topical events, but with some strange and entirely fictional quirks. I’m having fun with it.

Okay, I think I’m done. Have fun noticing Hallowe’en. I’ll be probably not doing that.

Read Full Post »

Well, WorldNetDaily have found something original to be horrified by. What new threat to all that is good and holy are they a-weeping and a-wailing and a-gnashing their teeth over this time? No, not gay marriage. Quite the opposite, actually.

Some conservative fruitcakes are objecting to the fact that marriages between people of opposite sexes are being referred to as… “opposite-sex marriages”. Perhaps they would have preferred a less biased and more family-friendly term, like “normal marriages”, or “marriages, but not, y’know, the faggy kind”.

You might be thinking that “opposite-sex marriage” is a sensible way of clarifying the type of marriage you’re talking about, since “same-sex marriage” is becoming a widely recognised thing as well. It’s kinda similar to how phrases like “snail mail” have become popular since the rise of email, since “mail” on its own became an ambiguous term.

You might be thinking that. But that’s probably because you’re not a total dick.

If you were a total dick, you might think that using the phrase “opposite-sex marriage” constituted lying to children. But then, if you were that much of a dick, you might also be Bill Donahue. Or a columnist for WorldNetDaily.

And if you were really so much of a dick as to be Bill Donahue – and I’m not saying you are, this is all just hypothetical – then you might object to the fact that children aren’t being told that “some male-on-male sex practices are dangerous”. You might even believe that use of the term “opposite-sex marriage” has any bearing on this whatever. It’s entirely possible that you’d also say things like…

Nor will it be pointed out that only so-called opposite-sex marriages are capable of reproducing the human race.

…while simultaneously being the kind of douchebag who starts screaming about the government forcing pornography on our innocent darling children every time anyone tries to give adolescent students some actual sex education. You’d also completely be missing the point, of course, that there are many states of existence that are incapable of reproducing the human race, like an opposite-sex couple being infertile, or a member of the clergy (of any sexual orientation) remaining celibate.

And I wouldn’t be surprised if you tried to claim that “Marriage means one thing”, apparently oblivious to the many different concepts of marriage that have existed in different times, places, and cultures. I doubt you’d understand that, if we allowed gay marriage rights, marriage would still mean one thing – in fact, it would still mean the same thing as it did before, just in a less prejudiced and limited way. You’d probably be too busy counting how often the New York Times used the phrase “opposite-sex marriage” and using whatever number you come up with as conclusive proof of how liberal values are destroying your country.

… You know. If you were a colossal dick.

Read Full Post »

Here’s a fun drinking game.

Watch this video of some homeopathic woo-merchant talking about mass-energy equivalence…

…and knock back a shot every time you involuntarily frown in bemusement and think: “What the hell are you talking about?”

It’s like she’s taken a book on general relativity for six-year-olds, mostly just looked at the pictures, then spent an hour banging her head against a wall so that the few sensible scientific ideas she learnt got all jumbled up in her brain with everything crazy that was already in there.

When she’s not getting something completely wrong, it’s generally because what she’s saying literally doesn’t mean anything.

Oh good god, I just got to “Stephen Hawkings gave us the string theory”. And it’s getting worse.

I… Okay, is this a stealth stand-up comedy show? This is genuinely worth watching all the way through. Maybe put down any sharp things first, but… wow.

Hat-tip to PZ.

Jesus, now she’s moved on to throwing a home-made explosive device at her neighbour’s house. And it’s an analogy for how homeopathy works. I am not making this up. I love this crazy bitch.

(Hey, I went a whole blog post without bringing up the latest #singhbca gossip. Aw, dammit.)

Edit 28/10/09: As in so many areas of awesomeness, Steve Novella surpasses me by far.

Read Full Post »

The British Chiropractic Association continue to plunge ever more convincingly away from competent discussion and toward incoherent babbling.

Alun Salt has done a little research, and it turns out the BCA seem to believe that they have discovered and translated ground-breaking ancient manuscripts, pre-dating any currently known written records of any kind from that part of the world. Their organisation generally has no focus at all on archaeology, or the study of ancient languages, which makes this accomplishment all the more impressive. They’ve surpassed numerous world experts, while totally playing down their skill and achievements in this area. The humility is truly inspiring.

Actually, Alun’s got the sarcastic angle covered pretty well in his own blog. It’s more likely the BCA have just been a tad carelessly imprecise with their reckoning of the exact figures. (Which is totally different from just making up some bogus crap, of course.) But this sort of thing is becoming characteristic of them, in the eyes of some. Is anyone surprised to learn that they’re making demonstrably implausible claims, and not doing a whole lot to retract or clarify these claims once their questionable nature has been pointed out? Or does that just sound like the sort of thing they’d do?

My level of content’s been a bit unremarkable here lately. Partly I’ve been distracted with a new soopah-sekrit project, which I’ll share with people soon if I don’t give up in a sulk after a week because it’s too difficult. I’ll try to keep saying more interesting things here as well.

Read Full Post »

What’s the connection, you ask? Well, they’re both the subject of the blog post you’re reading now.

Yeah, I’m not really tying them together in any way. Actually I’ve just thought of a way I could. When Crispian Jago drank a homeopathic dilution of his own urine, common knowledge states that some small number of the water molecules from his sample had also once been drunk by Adolf Hitler.

And because the most potent homeopathic solutions are the ones containing the least active ingredient, and because the number of Hitler-water molecules he was starting with was statistically very small… Crispian Jago absorbed into his system a potion that was almost 100% essence of Hitler. Holy crap.

I swear that literally just occurred to me as I was typing it. I’m going to have to let that sink in and examine the ramifications more thoroughly at some later time.

For now, I’ll just get on with what I was going to say.

The Journal of Alternative and Complementary Medicine sounds like a pretty official, mainstream, reputable journal, right? Just going by the title, it doesn’t exactly sound like a wacky fringe part of the Alternative and Complementary Medicine movement. It’s not using all sorts of long-winded buzzwords to try and make itself sound relevant while actually just being churned out by a couple of hacks with access to paper and crayons. It’s a proper journal. It’s the journal for this branch of medicine, with proper peer review and everything.

They also don’t seem to mind publishing utter, undeniable bullshit.

I don’t know who Dr Lionel Milgrom is, but he’s apparently someone people have heard of in the realm of homeopathy. The JACM printed an article of his recently, in which he apparently said this:

The British Chiropractic Association recently won a libel case against the science writer and CAM “skeptic” Dr Simon Singh for publishing an article in a British newspaper in which he accused them of promoting “bogus” treatments.

The judge agreed with this argument, awarding the BCA substantial damages.

Um. No. Neither of those things has happened. Nothing that even sounds like either of those things has happened if you’ve had at least one sensory organ functioning properly and pointed in the general direction of the English courts lately.

I just… it’s bewildering. It’s not even like this is some subtle point of legal technicality which it’s easy to misinterpret. When your fact-checking is this much worse than mine, you have serious problems.

Jack of Kent is all over this one. It’s really funny. I particularly like the bit where Milgrom tries to explain what the libel suit was about, but accidentally ends up arguing part of Simon Singh’s defence for him.

The racism part was going to be about this excellent post looking at the recent tabloid vilification of Nick Griffin and placing it in the context of some of the tabloids’ own recent headlines. Well worth a look, though I’m too lazy to add my own commentary now.

I have no other news, except that I also left another comment on this article earlier, because some idiocy just keeps coming back.

Night night.

Read Full Post »

If centuries of theology and philosophy and religious apologetics and dialectic debate haven’t been enough to persuade you of the totally genuine and absolutely real existence of God, then get ready for something that might finally tip the scale.

A nine-month-old child, somewhere in “southern Russian [sic]”, has been having verses of the Quran appear on various parts of his body in some sort of pink writing. They apparently turn up twice a week, and fade away over a few days. You know, similar to the way that ink might do if someone was writing things on him. This kid’s become quite the popular celebrity, with thousands of people turning up from all around to witness the miracle of words appearing on an infant boy’s body and his parents denying they put them there with a pen.

We’re told that “Local doctors have not been able to explain the phenomenon.” Now, I don’t know how many qualified medical practitioners have looked at the kid. But I’m thinking this might be true in the same way that parents have not been able to explain how Santa Claus delivers presents to hundreds of millions of children in one night. They could probably come up with one explanation, if pushed, but… well, that’d just spoil all the fun.

I really don’t get people sometimes. There’s so little inclination to question or doubt here, it’s like it doesn’t matter whether it’s true or not. It’s just important to believe in something.

In less crazy news, Derren Brown’s latest Science of Scams video is up. It’s about ouija boards, and has a demonstration of a test devised yonks ago by Michael Faraday, which I’d never seen before but is quite ingenious. I’m still really enjoying this series.

Read Full Post »

Older Posts »

%d bloggers like this: