Post-Slump Links

March 11, 2007

Since every hour that passes I’m more certain I’m not going to keep blogging, here are a few good links for your perusal:

Stuart Staniford of the Oil Drum explains carefully why the Saudi production decrease is due to peak oil rather than a voluntary reduction. The minutiae of the Saudi production curve are more consistent with a post-peak slump rather than with a voluntary reduction meant to give Saudi Arabia the power to flood the market at any given time.

C. L. Hanson notes that the two basic principles of relationships – that people have the right to say no to sex and that people shouldn’t sleep with anyone but their partners – are incongruous. As such, she talks about how cheating can save relationships.

Stentor rebuts market-based arguments against environmental legislation. He explains specifically that air pollution needs to be curbed collectively since air is naturally a shared resource. This isn’t an especially novel argument – the tragedy of the commons is a recognized market failure – but some libertarians’ hostility to it requires repeating it more than should be necessary.

Melissa Franklin, Harvard’s first tenured female physics professor, speaks at a conference about women in science that has just given her an award. She recounts experiences ranging from students’ crying because they couldn’t finish their problem sets to sexual assault.

More Carnivals

March 2, 2007

I’m not sure why I missed Help Us Help Ourselves yesterday, but I did. The carnival’s posted on the 1st of every month, so it’s not as if it was hard to remember.

Also, there’s a new carnival in town, dealing with issues of women in science (and engineering, and math, and technology): Scientiae. The first edition features many good posts about discrimination against women in the academia; the highlights are Am I a Woman Scientist?’s writeup about why women publish less than men, and Female CS Grad Student’s experience with being the only female in her graduate electrical engineering class. The next edition will be posted on 3/15 on Post Doc, Ergo Propter Doc, but the submission deadline is 3/12.


March 1, 2007

The seventh installment of Philosophia Naturalis, the quadriweekly carnival of physics and technology, is up on Geek Counterpoint; the highlight is John Conway’s two-part series about the search for the Higgs boson. The next carnival will be posted on March 29th; the carnival webpage is here. Note that although the host is not yet publicly posted on the carnival webpage, the next available hosting opportunity is on 5/24.

The 33rd Carnival of the Liberals is up on Blue Gal in a Red State. The next edition will be posted on Brainshrub on 3/14.

The 108th Carnival of Education is up on Dr. Homeslice. No highlight is offered, although there were a few possible candidates. The 109th carnival will be hosted on 3/7 on What It’s Like on the Inside.

The Skeptics’ Circle is now up on The Second Sight, with a special numerology theme. The highlights are Hlynes’ takedown of yet another a scare story about genetically modified food and Phil Plait’s rant about the story of the creationist who got a Ph.D. in geoscience and made national headlines.

And, of course, remember that the Carnival of Mathematics is up on Michi’s Blog on 3/9 and the next Carnival of the Godless will be posted on Hell’s Handmaiden on 3/4.

The Teachers’ Union is the Source of All Evil in the World

February 27, 2007

Shelley finds a flowchart that documents how hard it is to fire a tenured teacher in New York, the idea being that if only the evil teachers’ union stopped demanding that teachers not be arbitrarily fired, the state of American education would be a lot better. Of course, as Mark Kleiman notes, in the South it’s already the case, and public schools stink even more than they do here…

Focusing on individual bad teachers misses the point. The point is that there’s a severe shortage of good teachers, which has gotten to the point that California has to accept teachers who flunk a tenth-grade-level reading test. Now, California’s schools are severely underfunded – per student funding in California is below national average even though housing prices are the highest of all states – but similar problems with teachers happen even with decent funding.

People who think the teachers’ unions are the source of all that’s evil in the world just focus on the wrong problem. There already exists a process for getting rid of bad teachers; it’s called not giving them tenure in the first place. And even if they’re fired, the state has to find an alternative teacher, typically a rookie who won’t necessarily be any better.

Look, you don’t need mega-pay to have good teachers. On average, schools in the US spent $8,300 per student in school year 2003-4, of which three fifths went to teacher pay and benefits. Stuyvesant’s per student spending is about the same (it was $8,200 in 2003 by a definition that leaves a small amount of spending out), so its teachers can’t be paid that much more, even though New York is hardly a cheap place to live in.

The American school crisis is mostly a low-income school crisis. Upper middle class suburbs like Westchester and Nassau Counties have non-selective public schools that do perfectly well. Part of it is because of an insane cash infusion, but that’s only true for some suburbs.

So it makes sense to ask how come low-income schools have teachers who stink. Is it because good teachers would rather get paid $40,000 a year to teach at a magnet school that produces Nobel Prize winners than get paid $40,000 to teach in a ghetto? Or is it because low-income schools naturally lack one of the most important control mechanisms, parental involvement (there’s a reason scripted learning works in low-income schools)? Or, is it really a funding question, with a few exceptions for glamorous places like Stuyvesant and Bronx Science.

Saturday Link Roundup

February 17, 2007

I wanted this roundup to be science-themed, but there’s been too few linkworthy science posts and too many political posts. Still, starting with the science, GrrlScientist reports about how sulfur particles cause some global cooling, which can be exploited to mitigate global warming. The only thing I have to say about that is to recall the Futurama episode where Fry says at a ski resort, “It’s a good thing global warming never happened.” Leela retorts, “It did, but the nuclear winter balanced it out.”

Orac writes about the dilemma of whether to allow individuals access to experimental drugs. He comes down strongly on the side of not allowing, explaining that,

The entire ruling also seems to rest on a misperception that there are “miracle drugs” out there that we will have to wait years for because the FDA is too slow to approve them. However, if there really were such a “miracle drug” that was amazingly effective compared to anything we have now, a large randomized phase III trial would not be necessary to detect its efficacy. Indeed, its efficacy would almost certainly show up in even a small phase I trial. There’d be examples of amazing tumor shrinkage or even outright cures. In reality, we don’t see these things in Phase I trials, because there are no miracle drugs, at least not yet. Because the effects of most new drugs against various tumors tends to be less than miraculous, we need Phase III trials to determine safety and efficacy.

Kevin Alexander Gray of Black Agenda Report skewers Obama as a bland, white-identified politician who’s not listening to the black community’s concerns. Obama happens to be black, but he’s not the black voters’ candidate; black voters prefer Clinton, who they’re backing by several percentage points more than whites do, while supporting Obama by no greater numbers than whites do. It could be due to unfamiliarity, but it could also be due to Obama’s failure to tap into traditional sources of black support.

Matthew Yglesias turns his attention to Iran. Scott McLemee has an entirely misguided column on Inside Higher Ed that accuses liberals of not caring about Iranian democracy. Matt Yglesias notes that he has no idea what he’s talking about. After all, American conservatives want to bomb Iran, a surefire way to cement support for the regime, while the liberals are letting the regime crumble under its own weight.

Via Ars Mathematica I found a long article in the New York Magazine about praise and self-esteem. The two-line conclusion is that praising children’s intelligence will only hurt them by making them complacent and causing them to view failures as embarrassments, while praising their effort will make them work harder. In addition, praise needs to be specific – e.g. “It’s good that you can concentrate for so long” – or else it will be perceived as disingenuous. Draw your own conclusions about education.

Carnival of Mathematics: Inaugural Edition

February 9, 2007

I’ve gotten plenty of submissions that span the entire gamut of math-blogging: education, pure math, applied math, debunking bad math – it’s all there. Only the gender distribution could be made slightly more equal (and that’s an understatement). I’m linking to the posters in roughly increasing order of mathematical difficulty, but don’t let my opinions deter you from reading the posts closer to the bottom.

First, Denise of Let’s Play Math has a long collection of quotes exhorting people to study mathematics. George Washington, Martin Gardner, Henri Poincaré, Abraham Lincoln, Galileo Galilei, Bertrand Russell – they’re all there.

Barry Leiba of Staring at Empty Pages uses modular arithmetic to solve a digit puzzle. The puzzle is based on writing any positive integer – say 8293 – and jumbling its digits and subtracting: 8293 – 3982 = 4311. Then delete a nonzero digit. Based on the resulting number, it’s possible to tell which digit you deleted.

P. Sternberg of Discreet Math links to various companies producing non-orientable material, like Möbius shoes and Klein bottle wool hats.

Heath Raftery writes about a probability paradox. Two dice are rolled, of which one is a 4. Given that, what is the probability that the sum of the two dice is a 7? Without further qualification – for example, “At least one die is a 4” – it’s obviously 1/6. And yet Heath’s professor maintained that the answer was 2/11.

Charles Daney of Science and Reason gives a brief history of algebra from the Middle Ages till the Renaissance. Whereas most accounts begin with a relatively modern mathematician, like Fermat or Euler, Charles begins far earlier, with Al-Khwarizmi, who invented the word “algebra” and after whom the word “algorithm” is named.

In the bad math department, Tyler DiPietro has a long rant fisking the arguments of Sal Cordova, an intelligent design proponent who makes dishonest arguments from information theory and computability theory in order to try refuting evolution.

JD2718 has a puzzle in plane geometry. A parallelogram is defined as a quadrilateral where two opposite pairs of sides are parallel. But there are other equivalent definitions, and other conditions that look like they define parallelograms but in fact don’t.

Science Pundit Javier Pazos tells an anecdote about John von Neumann and the bee problem. The bee problem involves two trains initially spaced 40 km apart and approaching each other at 20 km/h, and a bee that flies at 40 km/h, starting from one train, flying toward the other, turning around when it meets it, flying toward the first train, etc. How far does the bee fly until the two trains meet?

Suresh Venkatasubramanian of GeomBlog has a long primer for the game theory of author ordering. When publishing a scholarly paper, each contributor wants to be as close as possible to first author in order to get more credit; Suresh explains which ordering strategies are stable and which appear the most utilitarian.

He also notes that the theory of algorithms is undergoing fundamental changes as computing power reaches saturation. In the past, it was sufficient for researchers to say that the run time of a process is proportional to some simple function, like x^2; but now, the constant that accompanies that function is becoming increasingly important.

John Kemeny introduces spigot algorithms, which can be used to systematically generate digits of some irrational numbers, including e and pi.

Jeffrey Shalit of Recursivity writes about the prime game. The initial observation is that the decimal representation of every prime p can be reduced to one of 26 primes by scrubbing off digits. That leads to a more general investigation of the concept of subsequences.

Eric Kidd programs infinity into Haskell, in order to solve such expressions as dividing infinity by 2 or adding 1 to infinity. The trick is to teach Haskell about the finite natural numbers first, and then write into it something strong enough to code for infinite numbers.

David Eppstein of 0xDE writes about subgreedy algorithms for Egyptian fractions. An Egyptian fraction is a representation of a fraction p/q as 1/n1 + 1/n2 + … + 1/n(k). A greedy algorithm is one that tries getting the best-looking result in one step without regard for efficiency in later steps; a subgreedy algorithm is one that is almost greedy, but tends to get far better results in the long run.

He also writes about a local version of the central limit theorem, which differs from the regular theorem in that it says repeated distributions look approximately normal in a small neighborhood of 0 rather than globally; and about coloring tilings in such a way that on the one hand the colors display a regular pattern, just like the tiling, but on the other no two adjacent tiles have the same color.

And finally, Mikael Johansson has multiple great posts about algebraic topology and related subjects; choosing three was a fairly hard decision. Of the three that made it into this edition, the easiest is the Borsuk-Ulam theorem, which roughly states that any given time, there’s a pair of antipodal points on Earth with the same temperature.

Also, A for the Layman explains algebraic topology, beginning with simple definitions and ending with an overview of homological algebra. For the braver souls, there’s his post about carry bits and cohomology; group cohomology is an indispensable tool in algebra, and Mikael applies it to addition and multiplication modulo 10, or in other words carry digits.

The next edition will be posted in two weeks, on 2/23, on Good Math, Bad Math. Send submissions to Mark CC, or to me so that I’ll forward them to him.

On a final note, I should remind everyone I’m still looking for someone talented enough to make a decent logo or banner for the carnival.

Generic Issues

February 7, 2007

1. I intended to dedicate this day to Giuliani, not McCain. So here it goes: Giuliani had nothing to do with the drop in crime in New York. The blue dot is when Giuliani’s predecessor, Dinkins, assumed office. The red dot is when Giuliani assumed office.


(The data comes from here)

2. Tyler blogs about a right-wing nut who complains that Israel is recognizing gay marriages performed in other countries: “The pro-family official’s concern, he explains, is that Israel’s acceptance of same-sex marriage will give ammunition to its Islamic enemies and fuel their propaganda.” Tyler notes that this is just the Dinesh D’Souza strategy of saying that conservative values are good because the terrorists hate liberal values.

My own comment on that is that the greatest number of Palestinian terrorist attacks is on settlers, who are fairly religious, and on targets in Jerusalem, a conservative city. Attacks on liberal Tel Aviv are the most spectacular, but while half of Israel’s Jewish population lives in Tel Aviv metro, far fewer than half of Palestinian attacks are on Tel Aviv metro.

3. Hat-tip to JD2718: Ray of Education and Technology rips into the Wall Street Journal, which decided to resurrect the meme that public school teachers work 7 hours a week. Based on calculating the number of hours they spend teaching, it arrived at an hourly pay figure of $34/hour. Based on calculating the actual number of hours they work, including teaching, staff meetings, and grading, $15/hour is closer to reality.

Also due to JD2718, the NYC Department of Education’s fetish for small schools combines the worst features of small schools and large schools. Ordinary small schools have their own buildings and are self-contained enough to teach 400-500 students independently. New York’s small schools share the same building with other schools, so they have to coordinate things like bells; a better way to describe them would be large schools supervised by committee.

4. Wal-Mart’s dreadful history of discriminating against women is finally resulting in a trial. Wal-Mart isn’t even denying that the discrimination exists, but instead tries weaseling out of a class action lawsuit and says individual women should sue individual stores.

In a way this is significant beyond Wal-Mart, because the company’s ridiculous claim that it “did not have a policy of discriminating against women” can help underscore a strict liability doctrine in civil rights cases. A corporation is responsible for making sure it’s an equal opportunity employer; if it isn’t aggressively punishing managers who discriminate, it’s exposed to class action lawsuits. It’s just how states are responsible for making sure their militaries don’t murder civilians when occupying a foreign country.

5. Hamas and Fatah are negotiating in Mecca. They’ve been negotiating for a while; while their leaders are talking to each other about how to forge a unity government, their foot soldiers are killing each other as well as any civilians who happen to be at the wrong place at the wrong time.