September 26, 2008

Structural Equation Modeling and Natural Systems, James B. Grace

The `structural equations' are what I would call systems of equations, which would be nothing out-of-the-way in modeling with differential equations. This is an explanation of how to set up and use such systems when you are beginning with statistics, specifically, linear relationships with error terms. There are lists and cookbook examples of how to map out relations and equations and get from there, eventually, to testable hypotheses about your actual system.

It's not written in the mathematical style, that is, it isn't deductive; it builds up from examples and rules-of-best-practice instead, with standards of how to draw the flowcharts that make them a notation for how you're thinking about the system (curved vs straight lines, for instance. There's a whiff of the drafting template in this, updated to drag-and-drop software).I think it's longer than a deductive exposition would need to be, but on the other hand the examples are useful for a different case of mind.

Nonlinear relationships are dealt with, but not very thickly; there are separate works on nonlinear structural equations.

Find in a Library: Structural Equation Modeling and Natural Systems

Posted by clew at 12:22 PM

September 20, 2008

Nine Times a Night

Nine Times a Night is a Renaissance poem about a widow who, being now economically independent, can choose a new husband for her own... pleasure. No-one is coerced, betrayed, murdered, or even dissatisfied at the end of the lyric, which makes it unusual in the works of Trad.

I don't know where the tune comes from, but here are lyrics and melody. Just now there's a YouTube version sung by Roberts and Barrand but scoring scenes cut from Pirates of the Caribbean movies; Trad. goes folk by way of Disney, commodious vicus.

It's also on a disc By the Tale of charming chanteys, vaudeville, bar songs, and ballads by a maritime duo Pilots of Tiger Bay, q.v.

Posted by clew at 08:59 PM

September 16, 2008

Dancing in the Streets, Barbara Ehrenreich

One of the minor questions in this "History of Collective Joy" is that of where dancing comes from, why it should be a universal action and pleasure. She hypothesizes that humans, or proto-humans, learned to do it to frighten off predators. The idea is that a group of people moving in unison look like a threat as big as the group, not a bunch of threats only as big as the puny individuals.

Now we know it works for giant honeybees, which do the wave to repulse wasps.

I can't remember if Ehrenreich extends the hypothesis to the possibility that moving in unison actually makes a group more dangerous to attack, but cooperation and communication are how humans now survive, and of course we do both with music. Dancing at predators might not be a false signal of a false size, but a true signal of a true skill, just as the bees also dance to each other when the wasps are gone.

The dance of the bees is a language; well, it has a grammar in the programming sense, although it's probably Not Done to refer to it as a language in the natural language sense... William Calvin sketches how the capacity for language might have arisen from the pre-processing needed to hit a rabbit with a thrown stone; the capacity needed to dance well is going to be harder to calculate (he neatly shows that the accuracy and speed needed to hit a rabbit, compared to the slowness with which signals travel through arm-muscles, mean that the whole throwing action is laid out in the brain before it's sent to the muscles to be executed there). Some of dancing is exactly unlike throwing the rock: there are many ways to bring a foot down at a given time, but the problem is to coordinate among all the dancers what that time is. And this implies a need for communication, and mirror-neurons and maybe rhythm, fired up exactly when the muscular activity is high. Irresistable just-so stories.

Find in a Library: Dancing in the Streets

Find in a Library: The Throwing Madonna

Posted by clew at 05:12 PM

September 07, 2008

Bitter Melon, Jeff Gillenkirk, James Motlow, intro. by Sucheng Chan

Locke is a rural Chinatown, maybe the only one surviving in the U.S. I don't think it's much architecturally; three blocks of frame houses built for floods, an enormous vegetable garden, and some levees. Bitter Melon is about the history seen in the surviving Chinese residents, and combines some old photographs with current ones and with transcripts of their reminiscences.

The town is unusual because U.S. discrimination against Chinese residents was so vicious for so long, forbidding them basic legal and economic rights and also the right to naturalize at all. Chinese communities were violently driven out of locales all over the West through the late 1800s (and probably later, but that's what I have a map of). For that matter, the Chinese were forbidden to naturalize or to own land as aliens throughout the West until 1952.

But, back to rural Locke; if driven out of most towns, and also the agricultural muscle of early California, where did the Chinese go? Most of them seem to have lived in field houses of large farms, or have been sharecroppers; Locke was unusual because it was a town run by the inhabitants and for regional Chinese workers, but it was on Locke land and the inhabitants didn't own it (until 2004!!). Which makes me think about various utopian and dystopian schemes, I must say; the river street was mostly run by and for the houses of gambling and prostitution, and then there were two blocks of houses, and then the community gardens, which are clearly managed to the inch so must have been surveyed and willed on.

The second most interesting thing, after the political wrongs done to the Chinese, is the view the survivors have of the rest of the country. Now, this is a delicate and nuanced thing; it's not as simple as the legal history, it's the impressions more or less tactfully conveyed by people with wildly different temperaments and histories. It's a good book to read on a hot afternoon when you miss your grandparents and can put up with some meandering in their memory. There's an interestingly contradictory line of comments about American blacks; that they were worse treated than the Chinese were, but some of the Chinese still dislike them, though certainly not all, and that whole civil rights noise was very un-Chinese... but admirable. The line on Mexican-Americans is a lot more straightforward, that despite more protective laws they are now what the Chinese were ninety years ago. And, although Locke was overwhelmingly in support of the Kuomintang, one resident remarks that the Chinese were treated horribly in the States until the U.S. was intimidated by Mao; you get the impression that someone who mightn't naturally approve of Mao had evidence that his ruthlessness was required, in this troubled world.

Third, I wanted more about the gardens; more than half the town by area, after all. These are vegetable gardens run by people who survived sharecropping, on the Delta soils of Yolo County which were rich to start with, and with a gardening tradition that wastes nothing. It's mildly famous that the Delta islands are losing topsoil at a measurable rate every year, as it blows away, decays away, and is stripped for turf. I would very much like to know if the Locke garden is shallower than it ever was. In the one photograph, it looks as convex and fluffy as the best feather bed.

Find in a Library: Bitter Melon

Posted by clew at 08:12 PM

September 03, 2008

The Country House, John Galsworthy

A family that is very bad at effectively loving each other, but considerably better at loving their country house, fumble through several linked emotional crises.

What, indeed, could be more delightful than this country-house life of Mr. Pendyce; its perfect cleanliness, its busy leisure, its combination of fresh air and scented warmth, its complete intellectual repose, its essential and professional aloofness from suffering of any kind, and its soup--emblematically and above all, its soup--made from the rich remains of pampered beasts?

Galsworthy is fairly straightforward about their merely human follies, but very, very slightly sarcastic about the follies of their class, so I could enjoy the real-estate fantasy without feeling like a total creep. (Ivy Compton-Burnett is a better author, but I feel like a horrible member of a horrible species after reading her books. Possibly she's enough better that I act like a slightly better person, but I don't think the effect is significant.)

Historical oddities; an landholder calling himself a "Tory Communist" because he quite consciously wants a conservative nanny state; "there were liberals [in the village] now that they were beginning to believe that the ballot was really secret"; "The Rector blushed. He hated tale-bearing--that is, of course, in the case of a man; the case of a woman was different--and just as, when he went to Bellew he had been careful not to give George away, so now he was still more on his guard."

Project Gutenberg etext 2772

Posted by clew at 03:28 PM
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