Last night I was singing “La cucaracha” while I gave Doug a bath. I was pronouncing the r with the Spanish pronunciation. This sound is often referred to as the tap or flap, and we also have it in English: It is the same sound you make for the t in atom, or the d in Adam. (It sounds a lot like a [d], but it’s not—try making a careful [d] sound in Adam, and it will sound strange.) I’ll transcribe this sound as D, so I was singing:
(1) La cucaDacha, la cucaDacha!
Doug starts singing it, too, but like this, with a regular, plain old English [r]:
(2) La cucaracha, la cucaracha!
Now why did he do that? If he were reading the word, I would expect him to pronounce the r as [r], but he’s never seen this word written! All he had to go on was what he heard me say, and he heard me saying [D]. Doug has been making the flap sound for years in dozens of ordinary English words (including his brother’s name, Adam), so why should he suddenly turn this one into an [r]? I mean, suppose Doug had heard me say some unfamiliar English word that contained a flap, such as adage. Would he repeat it as arage? I can’t imagine he would.
There is, however, one difference between the flap in English words such as Adam the and the flap in Spanish words such as cucaracha. In English, the flap always occurs after a stressed syllable and before an unstressed one. For example, if we write out Adam with D indicating the flap and boldface underline indicating the stressed syllable, we get ADam. But doing the same thing with cucaracha, we get cucaDacha. So maybe Doug was picking up on the difference in stress. I tried an experiment with just the cara part of the word:
Me: Say caDa
Doug: caDa
Me: Say caDa
Doug: cara
How about that? He’s got the English flap rule well-internalized … as of course he should, being a native speaker of English. I’ll have to try a few other nonsense syllables with flaps in them to see what he does.
Friday, April 02, 2004
Gotcha, Cucaracha
Thursday, April 01, 2004
The Ramblin' Linguist Returns
My brother Neal has consented to join Agoraphilia for another guest blogging stint, this one of indeterminate length. Welcome back!
The Significance of Insignificance
Remarking on some recent poll results, Eugene says, "Repeat after me: I will not think that statistically insignificant changes in poll results are statistically significant -- even if I really, really like them."
In general, I agree with Eugene’s point (which he has made many times): people ascribe way too much import to small differences in polling results, without paying attention to the margin of error.
However, Eugene’s position may foster the false impression that all differences in poll results that fall within the margin of error are equally insignificant. Suppose that two candidates are separated by just 2 percentage points in the polls (say, 49% to 47%), and the margin of error is 3 percentage points for each figure. And suppose that two different candidates in another election -- or the same two candidates in a later poll -- are separated by 6 percentage points (say, 51% to 45%), again with a margin of error of 3 percentage points for each figure. While both differences are “insignificant” in the sense that the difference is within the combined margins of error, the latter result is clearly more significant than the former.
Indeed, the latter result would most likely have been deemed statistically significant had a very slightly lower level of confidence been applied. The margin of error is constructed using a conventional but essentially arbitrary confidence level. The typical convention is 95% confidence, but other levels of confidence could also be used; 90% and 99% are relatively common. These are the confidence levels employed by scientists, who don’t want to affirm a hypothesis unless they are very confident of it, and who are willing to remain agnostic in a wide range of cases. Lower levels of confidence might well be acceptable in other contexts, such as business, where some decisions have to be made without great confidence (e.g., should I plan to expand next year if I am 75% confident that consumer demand will pick up?). It’s not obvious what the appropriate level of confidence is for political prognostication, but I’ll put it this way: in the example given above, I would be willing to bet a larger amount of money on the second race than the first.
The broader point is that statistical significance is not an all-or-nothing proposition. Despite the way statistical significance is often taught, there is not a sharp discontinuity between significance and insignificance. Significance lies on a gradient.
Wednesday, March 31, 2004
Dietary Efficiency
Economists’ and engineers’ minds are very similar, as indicated by (among other things) the fact that many economist jokes are recycled engineer jokes, and vice versa. It’s no coincidence that my dad is an engineer. But one major difference between them is their notions of efficiency. Engineers’ notion of efficiency is typically driven by the physical or technological relationship between inputs and outputs. Economists’ notion of efficiency, on the other hand, is typically driven by subjective human valuations.
Here’s a nice illustration: What does it mean for the human body to be “a more efficient machine”? That’s a phrase you’ll sometimes hear about the alleged effect of dieting and exercise on the human body. To an engineer, a more efficient human body would presumably be one the generates the greatest amount of energy (or work) from a given amount of caloric intake. But I suspect that is not the kind of efficiency people want out of their bodies, at least in the modern age of cheap food. What most people (or Americans, at any rate) really want is a body that burns up lots of calories without really doing much with them. We want to maximize the amount of tasty food we can ingest without having to exert energy to lose the calories. And we don’t even want the calories to be stored; that just means fat. Nope, what we want is to waste calories.
The point is that our bodies could be inefficient from an engineering perspective and yet economically efficient. Economic efficiency is measured in terms of preference satisfaction, and a body that “wastes” lots of calories actually makes many of us happier.
ADDENDUM: Just to be clear, I realize that engineering efficiency could be “tweaked” to make it isomorphic to economic efficiency. It’s just a matter of redefining what the relevant inputs and outputs are. My point is about how notions of efficiency are typically deployed by the two professions. Specifically, economists usually place much greater emphasis on the subjective aspect of the problem.
Monday, March 29, 2004
The Two Things about the Two Things
A couple of months ago, I blogged about the two things. Lots of people commented, and others replied on their own blogs. As a result, I now know…
The Two Things about the Two Things:Why do people love to play the Two Things game? I suspect it's because two is a welcome change from the hackneyed three. Three leaves room for fluff, while two forces you to give a lean and mean summary of what's really important, without the padding. And why do computer people love the game even more? On that one, I'm unsure. It could be the result of the inherent bias of having asked the question on the web. Or it could be the whole binary thing, though no one went so far as to call their list the "10" Things.
1. People love to play the Two Things game, but they rarely agree about what the Two Things are.
2. That goes double for anyone who works with computers.
I have now created a Two Things webpage, which includes all the Two Things entries I’ve found thus far. Please feel free to send me more, and I’ll update the list periodically.
(In the earlier blog post, I promised to post only the best entries. But there was lots of disagreement, especially for anything computer-related, so I decided to just post them all and let the reader decide.)