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Wednesday, January 31, 2007

A Stab in the Dark

Lawrence Block’s 1981 Matthew Scudder mystery, A Stab in the Dark, has recently been reissued in audiobook format. If you’ve only read some of the recent Scudder novels, where he’s a non-drinking alcoholic, you’ll find that A Stab in the Dark fills in most of the back story. It’s also an absorbing, entertaining, and transparently well-written mystery — very New York, very introspective, very much in the sensitive-but-hard-boiled-detective vein. I have to agree with the AudioFile reviewer’s observation that the narrator in the audio version (William Roberts) is expressive and yet “somehow off,” but the expressiveness wins out in bringing both the novel and the main character to life. Whether you read it or listen to it, you will enjoy A Stab in the Dark.


Tuesday, January 30, 2007

Maybe we should try this in high school

Rudbeckia Hirta, the pseudonymous math professor from a state university in the south, recounts a story with a delicious little idea at the end:
So today I saw one of the football players in the class sending text messages on his cell phone. I say to him, “You don’t need that now. Put it away.” And he was like, “I’m using the calculator to calculate.” Unfortunately for him, at the time the board looked like:

(I was getting ready to write: “Show that there must be a prime number > 5.”)

So I responded, “All we have so far is 5. We don’t even have an operation. You don't need a calculator for 5.”

He sulked and put it away.

What I wish I had was his phone number (which I don’t because he added after the first day, and I collected that information on the first day) and a Bluetooth cell phone that worked with Address Book because then I would send him an SMS message via my laptop (probably something like “Stop texting during class”), projected on the screen in the front of the room for all to see.
Maybe that’s an idea that we could try in Weston — not that any of our students would ever text in class — oh, no, not in Weston.

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Monday, January 29, 2007

Wikipedia revisited

My students have had a hard time finding any errors in Wikipedia (one of their assignments). Of course there are plenty of errors in it, so why was it so hard to find them? I think the issue is that most high-school students can’t find topics in which they have deep expertise, and it’s difficult to identify what’s wrong with an account of a topic in which you aren’t an expert.

As I’ve indicated earlier, the articles that concern mathematics, computer science, and some other technical domains are remarkably accurate — not that they’re free of errors, but they’re certainly as good as many printed textbooks. I assume that there are two reasons why this observation might in fact be true: contributors are rarely motivated to slant a technical article out of political or emotional bias, and writers are unlikely to spend the time to compose a math article if they don’t know what they’re writing about. So the two major sources of error — bias and ignorance — are greatly reduced in these cases.

Wikipedia has been in the news a lot recently. For instance, Mark Bernstein posts three entries in his blog: What Wikipedia can do well, WikiPolicing, and Wikipedia Biography. Here are a few of his interesting observations:
Where is wikipedia best? The most effective articles share some common properties:
  • Of potential interest to a wide audience
  • Of vital interest to very few
  • Impersonal
A wikipedia article on cycloctatetraene (one of my old friends) is likely to be good. Lots of people might be interested in cyclooctatetraene. Nobody cares terrible about it. Nobody loves or hates it. (I have a sneaking, nostalgic affection for it, but that’s just my and my COT).

A wikipedia article on a controversial, living person is almost bound to be a combat zone.


Wikipedia is terrific for lots of uncontentious corners. As Diane Greco points out, the Vietnam War is still being fought on Wikipedia and that page is unlikely to reach consensus or achieve stability.

But if you want to know when Lord Acton wrote, or check exactly when Galileo died, Wikipedia is remarkable good. That’s not everything, but it's a lot.

Wikipedia has strengths. It’s useful. We shouldn’t expect it to be take on tasks for which it is poorly suited, tasks like contemporary biography. And its internal regulatory systems needs to be repaired, lest it be owned by an anonymous bureaucracy of axe-grinding children. This can all be fixed.
For various reasons, many of them rather obvious, it’s not a good idea to cite a Wikipedia article as an authoritative source in a bibliography for an academic paper. But it can be a great source of basic information, a quick way to acquire initial knowledge that can be confirmed or questioned in later research. Only the lazy would use it as the last word.

Not surprisingly, the Chronicle of Higher Education has its doubts:
Among academics...Wikipedia continues to receive mixed — and often failing — grades. Wikipedia’s supporters often portray the site as a brave new world in which scholars can rub elbows with the general public. But doubters of the approach — and in academe, there are many — say Wikipedia devalues the notion of expertise itself.

Perhaps because of the site’s refusal to give professors or other experts priority — and because of an editing process that can resemble a free-for-all — a clear preponderance of Wikipedia’s contents has been written by people outside academe. In fact, the dearth of scholarly contributions to the site has prompted one prominent former Wikipedian — Larry Sanger, one of the site’s co-founders — to start an alternative online encyclopedia, vetted by experts.
It always makes me nervous when academics consider themselves to be a priesthood that must intercede between hoi polloi and the truth. Maybe that’s one reason why I’m a math teacher: mathematical truth can be discovered by anyone and vetted by anyone, regardless of credentials. Leaving truth to the experts alone can be dangerous. Do read the entire (long) article from the Chronicle of Higher Education which I’ve excerpted above.

Even the establishment New Yorker and the slightly alternative Boston Phoenix get into the act:
...just look at Wikipedia.com, which, with just five employees and an annual operating budget of $750,000, has become the 17th most popular site on the Web, boasting more than a million articles about every subject imaginable, written by hundreds of thousands of people across the globe. Compare that to the Encyclopedia Britannica’s measly 120,000 entries. Since its launch in January 2001, Stacy Schiff writes in a recent New Yorker article (from which those numbers are gleaned), Wikipedia has succeeded in realizing the dream of H.G. Wells, who “prescribed a ‘world brain,’ a collaborative decentralized repository of knowledge that would be subject to continual revision.”

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Sunday, January 28, 2007

Romantic pairings: inappropriate for high school?

No, it’s not what you think. Of course there are romantic pairings in high school, and there’s no point in considering them inappropriate. But that’s not what this post is all about. The question is whether a precalculus class that’s studying combinatorics should be given the following cartoon from xkcd:

The mathematics is impeccable, the content is surely of interest to students, so what’s the problem?

Actually, I don’t think there is any problem. But some of my colleagues think that it’s inappropriate for high school and would offend some students and/or their parents, even at Weston. What do you think?

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Saturday, January 27, 2007

Watch Your Back!

I recently read another funny novel by Donald Westlake, Watch Your Back!, and I can recommend it to anyone with a sense of humor. Though nominally in the thriller genre, this entrant in the Dortmunder series manages to combine convincing character development with a plausible story line (well... somewhat plausible) and a hilarious plot. Things go wrong, things go right, it’s hard to tell the good guys from the bad guys — all in all, it’s a well-written page-turner that’s non-stop fun. If you like this sort of thing, read it! If you don’t, stay away.


Friday, January 26, 2007

Once again, addressing the achievement gap

We had a day-long workshop last week on the achievement gap, which I’ve discussed in various earlier posts. What troubles all of us is that our black and Latino students (mostly from Dorchester, Roxbury, and other Boston neighborhoods) get significantly lower test scores and GPAs than our white and Asian students (almost entirely from Weston). Furthermore, a significantly lower percentage of the first group is in honors and AP courses, and many more of them withdraw from such courses after the deadline, thereby earning a grade of W. This, of course, is a nationwide problem, not just one in Weston — in fact, we have a smaller achievement gap than elsewhere.

This topic is one that many people are uncomfortable with and therefore don’t want to discuss. But it’s important to confront it and try to find solutions, so that’s what we did. It was generally a productive day, with a good balance between an analysis of the problem and proposals for a solution.

I have tentatively reached the following conclusions at this point:
  • Cultural differences are a major factor, but we can do nothing about them.

  • Summer programs, on the other hand, could make a major difference. The gap is widest in September and narrowest in June. Given the geographical gap and the time it takes to commute, summer programs in Boston (or accessible by public transportation) would be particularly helpful.

  • Black and Latino students don’t see their peers in honors and AP courses, and don’t see black and Latino teachers either. (I’m talking about Weston here, not elsewhere.) Changing this fact could have a major impact. But how do we change it?

  • There is an inherent contradiction between asking for increased honors/AP enrollment by black and Latino students and also asking for increasing GPAs: if more margin students take such courses, their grades will inevitably drop. We’re caught between a rock and a hard place, and I see no possibility of having it both ways.

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Thursday, January 25, 2007


If you have any interest at all in crossword puzzles, you will definitely enjoy Cruciverbalism: A Crossword Fanatic’s Guide to Life in the Grid, a small but well-written book by Stanley Newman and Mark Lasswell. Fascinating, amusing, and full of information, this non-fiction work tells you everything you want to know about crossword puzzles, including the significance of the sequence of editors of the standard-setting New York Times puzzle. Those of us who remember Margaret Farr, Eugene Maleska, and Will Weng — and who now are devoted fans of Will Shortz — will eagerly devour Newman and Lasswell’s account, which grabs the reader’s attention from the very first paragraph by throwing the reader right into the middle of the action. I know, you might say that there can’t possibly be action in crossword puzzles, but you would be wrong. Read this lively and engaging book to find out how: you’ll learn a lot and will be entertained in the process.


Wednesday, January 24, 2007

Arsenic and Old Lace

Arsenic and Old Lace is definitely a classic film, so that means I’m supposed to like it — right? I don’t know why I had never seen it before, but I finally got around to it the other day. Unfortunately I was disappointed. Cary Grant was unconvincing in the lead role, and nothing about this movie held my attention very much. The best actors were Grant’s aunts, played by Josephine Hull and Jean Adair. (Maybe I should have heard of them, but I hadn’t.) While screwball comedy has never been one of my favorite genres, I usually like it better than I liked this one. There are some amusing lines, but on the whole I don’t think it’s worth seeing.


Monday, January 22, 2007

Off by two ems

There’s a flaw in the typography of the sign outside my dentist’s office. It’s neatly lined up in two columns, starting something like this [names changed to preserve anonymity]:

John Smith, DMD
Mary Jones, DDS
Joe Gummer, DDS
Rhonda Radical, DDS   
General Dentistry
Dental Surgery

But that isn’t actually how it looks. Poor Dr. Gummer’s line is misaligned, so the sign actually looks like this

John Smith, DMD
Mary Jones, DDS
Joe Gummer, DDS
Rhonda Radical, DDS   
General Dentistry
Dental Surgery

I thought I should tell my students about this discovery, but Barbara claims that they would consider me too geeky for words. I replied that they already know that about me.

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Saturday, January 20, 2007

The Rottweiler

The Rottweiler is another excellent book in Ruth Rendell’s collection of thrillers (as distinguished from her Wexford detective novels). There is a richly developed cast of characters, including one who is the favorite suspect of the police but who the reader knows is not the serial murderer. This character has Fragile X Syndrome, which I had never heard of before. But, as any good book does, The Rottweiler motivated me to learn more. Just Google it and you’ll find out what you need to know.

Anyway, in standard thriller fashion (as opposed to detective stories), Rendell reveals the murderer’s identity to the reader early on. Actually, it’s about a hundred pages in, and it could easily have been earlier. But you don’t read this sort of book for suspense; you read it for the character development, the setting, and the evolving discovery of the truth. Rendell succeeds in all three areas. I found it totally absorbing. The novel creates a believable world with a cast of believable characters. Humorous subplots help lighten what would otherwise be a rather somber plot. Read it!


Thursday, January 18, 2007

Excellence without a Soul

I highly recommend Excellence without a Soul: How a Great University Forgot Education, by Harry Lewis. Though nominally about Harvard, it’s really about a much larger domain, including not only elite universities but also elite public high schools such as Weston High School. A well-known computer science professor who recently resigned his position as Dean of Harvard College to return to full-time teaching, Lewis offers a searing indictment of how our leading academic institutions treat their “customers.”

You might expect a lot about Larry Summers in this book, especially since the commonly accepted rumor is that the reason Lewis went back to teaching was that Summers pushed him out as dean. Maybe so, maybe not. There certainly is some interesting material on Summers here, especially the analysis that discounts the common wisdom that attributes the former president’s unpopularity to his style and his lack of social skills (Lewis claims that it was actually due to incompetence). But on the whole there is no significant emphasis on Larry Summers. And you might expect a lot of criticism of grade inflation, but actually Lewis shows through convincing statistics that grade inflation at Harvard is no more severe than it ever was, and that it was definitely not caused by affirmative action and sympathy for draftees in the 1970s. (In fact, that turns out to be the one decade when grade inflation was actually flat!) So neither of these topics dominates the book, which actually emphasizes cultural and academic issues, such as treating students and their parents as customers.

I’ll write in much greater detail later on, but for now all I can say is that this book should be read by the entire Weston faculty and by anyone else who cares about high standards at our top high schools and colleges.

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Wednesday, January 17, 2007


We tried to watch Somersault, acclaimed all over Australia. It looked like it might be of interest to film buffs and to anyone who works with teenagers (or anyone who has a teenager in the family). But neither Barbara nor I could bother finishing it. We both found it uninspiring, routine, and even boring. Maybe we both missed something.

Here are quotations from three respected movie critics. First, from Stephen Holden of the New York Times:
“Somersault,” which the Australian Film Institute garlanded with 13 awards, including best film, director, actor and actress (for Ms. Cornish’s astonishing performance), is a movie about the looks on people’s faces and the disparity between the surface and the roiling chaos beneath. Cool-headed and emotionally distanced from its characters, it trains an X-ray eye on their precarious balancing of civilized and bestial impulses.
And then our own Ty Burr, from the Boston Globe:
'“Somersault,” in other words, is about that time in young people’s lives when they understand that no one can define them but themselves, a prospect that can scare them into noisy compensatory behavior. Heidi has (or thinks she has) one asset, but her needy lust keeps blowing up in her face. Why does being available turn people against her? How can sex promise such closeness only to deny it?
And from Michael Wilmington of the Chicago Tribune:
“Somersault” is a small film, done with limited resources, but it’s impressive — and so is Cornish.
Well, as I say, maybe I missed something. If you see this film and enjoy it, tell me what I missed.


Tuesday, January 16, 2007


I just came across this clipping I had saved from the Boston Globe some years ago. Unfortunately, I don’t know the date, and it’s not really worth the trouble researching it. It quotes Joe Cazazza. who has finally retired from his long-held position as Commissioner of Public Works for the City of Boston:
“For every ten people you ask, seven will say, ‘Great, we have a clean street,’ ” said Casazza. “The other two will hate you for life.”
The seven must live in certain neighborhoods...

I don’t know about the missing one.

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Thursday, January 04, 2007

A Madman Dreams of Turing Machines

Too often the books I review are mysteries (or novels in related genres, such as psychological thrillers). But not this time (and not next time either). Today we’re talking about a straight, mainstream novel — more or less.

As you can guess from its offbeat title, physics professor Janna Levin’s A Madman Dreams of Turing Machines is not exactly a typical work of fiction. Maybe it would be appropriately labeled historical fiction — well, again, more or less. On the surface it’s a slightly fictionalized version of the lives of two of the most important mathematicians of the twentieth century: the Englishman Alan Turing and the Austrian Kurt Gödel. In a slender 230 pages it is of necessity very selective, and of course the novelist’s purposes make it even more so. What’s most interesting is the interplay between the contrasting worldviews of Turing and Gödel — mechanization vs. uncertainty. Levin’s style is also quite interesting and will not be everyone’s cup of tea. She writes in a rather non-traditional manner, which you will like if it captures you. Otherwise you may just agree with the Cambridge reviewer (our Cambridge, not Turing’s) who thinks that Levin just doesn’t know how to write and that her editors just don’t know how to edit. He’s wrong, but I can see why he thinks that “the prose is unbearable.” If you can’t jump into the spirit of this book, you will indeed find the prose unbearable. But give it a try, without any preconceptions of a prose style that you want to impose on the author, and you may find it a rewarding experience. I did.

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Wednesday, January 03, 2007

Hey, Verizon, $.02 does not equal .02¢

You have to listen to this actual mind-boggling conversation between a Verizon Customer Service manager and a Verizon customer. Here is the first astonishing excerpt:
Customer: Do you recognize that there’s a difference between point zero zero two dollars and point zero zero two cents?

Manager: (after another long pause)... They’re both the same, if you look at it on-paper-wise.
This customer had been quoted a rate of 0.002 ¢/kilobit for service in Canada, and then Verizon ended up charging him 0.002 $/kilobit, claiming that it was the same thing. You really don’t want to listen to the entire recording — I didn’t — as it’s quite long and all goes on and on in the same vein, but the first couple of minutes are distressingly priceless... and then the manager keeps insisting that it makes no difference whether the units are cents or dollars. He says that his calculator gives him the right answer, but the calculator of course doesn’t include units. Even when the customer points out that 20,000 cents would not be an acceptable payment for a $20,000 car, the manager insists on ignoring the units and wants to charge 100 times the quoted rate. As the science teachers would tell us, units do matter.

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Monday, January 01, 2007

“Don’t think about thinking, it’s not on the test”

On NPR’s Morning Edition today there was a story about education and standardized testing, which included a debut performance of “Not on the Test” — a “gentle lullaby for students across the country” by Tom Chapin and John Forster. Do give it a listen.



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