kitchen table math, the sequel: 7/20/08 - 7/27/08

Saturday, July 26, 2008

for all you content freaks out there

A couple of years ago Carolyn decided that's what ktm-types are: content freaks.

Well, good news! I have discovered the ultimate content freak product: SuperMemo.

Actually, I rediscovered it. A couple of years ago I came across SuperMemo in my wanderings and didn't know what to make of it. It sounded good -- it sounded great -- but who were these people? Offhand, I couldn't tell whether SuperMemo was the brainchild of some crackpot internet nut or some crackpot genius internet nut. So I filed the URL and planned to get back to it when I had more time.

Then I forgot about it until it popped back up a few weeks ago in a Wired article, which I printed out and also forgot. (Once I have my very own copy of SuperMemo and have figured out how to operate the incremental reading feature, this kind of thing won't happen to me any more.)

A couple of days ago the print-out surfaced, and there you have the Living History of my journey to SuperMemo and extreme memory:

Piotr Wozniak's quest for anonymity has been successful. Nobody along this string of little beach resorts recognizes him as the inventor of a technique to turn people into geniuses. A portion of this technique, embodied in a software program called SuperMemo, has enthusiastic users around the world. They apply it mainly to learning languages, and it's popular among people for whom fluency is a necessity — students from Poland or other poor countries aiming to score well enough on English-language exams to study abroad. A substantial number of them do not pay for it, and pirated copies are ubiquitous on software bulletin boards in China, where it competes with knockoffs like SugarMemo.

SuperMemo is based on the insight that there is an ideal moment to practice what you've learned. Practice too soon and you waste your time. Practice too late and you've forgotten the material and have to relearn it. The right time to practice is just at the moment you're about to forget. Unfortunately, this moment is different for every person and each bit of information. Imagine a pile of thousands of flash cards. Somewhere in this pile are the ones you should be practicing right now. Which are they?

Fortunately, human forgetting follows a pattern. We forget exponentially. A graph of our likelihood of getting the correct answer on a quiz sweeps quickly downward over time and then levels off. This pattern has long been known to cognitive psychology, but it has been difficult to put to practical use. It's too complex for us to employ with our naked brains.

Twenty years ago, Wozniak realized that computers could easily calculate the moment of forgetting if he could discover the right algorithm. SuperMemo is the result of his research. It predicts the future state of a person's memory and schedules information reviews at the optimal time. The effect is striking. Users can seal huge quantities of vocabulary into their brains.

Want to Remember Everything You'll Ever Learn? Surrender to This Algorithm
By Gary Wolf
Wired Magazine

memory is good

The problem of forgetting might not torment us so much if we could only convince ourselves that remembering isn't important. Perhaps the things we learn — words, dates, formulas, historical and biographical details — don't really matter. Facts can be looked up. That's what the Internet is for. When it comes to learning, what really matters is how things fit together. We master the stories, the schemas, the frameworks, the paradigms; we rehearse the lingo; we swim in the episteme.

The disadvantage of this comforting notion is that it's false. "The people who criticize memorization — how happy would they be to spell out every letter of every word they read?" asks Robert Bjork, chair of UCLA's psychology department and one of the most eminent memory researchers. After all, Bjork notes, children learn to read whole words through intense practice, and every time we enter a new field we become children again. "You can't escape memorization," he says. "There is an initial process of learning the names of things. That's a stage we all go through. It's all the more important to go through it rapidly." The human brain is a marvel of associative processing, but in order to make associations, data must be loaded into memory.


I speak as a person who writes nonfiction for a living. You cannot write a book about a subject in which you aren't expert without committing the vocabulary of the field to memory.

Google isn't memory.

The internet isn't memory.

The World Book Encyclopedia isn't memory.

spaced reptition: To write a book, you have to learn the vocabulary of the subject you are writing about. Also the schema, (pdf file - NOTE: I've read only the first page of this article) to the degree that you can.

And learning means committing to memory.

End of story.

Thursday, July 24, 2008

clickers for college

Ohio State University students who used the devices to answer multiple-choice questions during physics lectures earned final examination scores that were around 10 percent higher – the equivalent of a full-letter grade -- than students who didn't.

The clickers also appear to level the playing field between male and female students. In clicker classes, male and female students performed equally well. In the traditional, non-clicker classes, male students outperformed female students.


Around the country, clickers are regularly used to maintain student attention in large lecture halls. At large universities such as Ohio State, even relatively advanced science classes may contain hundreds of students. Reay said that clickers are a good way to help students pay attention and learn in today's classroom.


In clicker classes, multiple choice questions appear on a large computer screen at the front of the lecture hall. Students hold the wireless devices, which resemble small calculators. They cast their votes for the correct answer based on their understanding of the part of the lecture that was just given. A bar graph shows the percentage of students voting for each answer.

Physics educators have expanded the use of clickers at Ohio State by developing sequences of questions to determine if students really understand the underlying concepts of a lecture. The technique involves offering a series of questions -- typically three -- each with different wording and structure, but all designed to test the same concept.

One three-question sequence that Reay and his colleagues developed is used to test students' understanding of Faraday's Law. The class is shown a diagram of two wire loops of different sizes moving into a magnetic field, and asked which loop will experience larger induced voltage at the moment it enters the field.

For an introductory electromagnetics class of engineering majors, this is an easy question and Reay would expect more than 80 percent to answer it correctly.

"But not all students choose the correct answer for the right reason," he said. "A common misconception is that larger loops always have a larger induced voltage, which is not the case. That's why we then ask two more questions that involve loops of different sizes and shapes. The question-sequence method eliminates common student misconceptions, and helps students grasp the underlying concept in a short time."

The idea with clickers, Reay explained, is that both lecturers and students can gauge whether students understand the material in real time. If students don't understand something, the lecturer might try to get them to think about the topic in a different way, perhaps by discussing it amongst themselves to encourage understanding before moving on to a new topic.

Professors typically devote approximately 20 percent of a class to clicker questions, and the rest to traditional lecture and discussion.


Students aren't required to use the clickers, but Reay said that participation over the years has held relatively constant at 90 percent. Small incentives, such as grading clicker questions or offering extra credit, can raise participation to 98 percent.

Students seem to like the clickers.

“When we conduct our quarterly surveys, we find that the percentage of students enthusiastically favoring use of clickers is higher than 90 percent,” Reay said.

"In addition to this popularity, our research indicates that our sequence method of using clickers offers students a significant advantage on learning, and we are working to sharpen our methodology for measuring these learning gains. We're finding that the timing of pretests and post tests during the quarter matters, along with different applications of incentives,” he added.

"In addition to this popularity, our research indicates that our sequence method of using clickers offers students a significant advantage on learning, and we are working to sharpen our methodology for measuring these learning gains. We're finding that the timing of pretests and post tests during the quarter matters, along with different applications of incentives,” he added.


Both sexes had nearly equal gains in the clicker classes: females had a score gain of 6.2, and males a score gain of 6.7. In the non-clicker classes, the female score gain was 4.3, and the male score gain was 6.6.

As to why clickers seem to help female students more than male students, the anonymity of the devices may offer an advantage. In surveys, nearly all the students -- male and female -- said they liked having the ability to keep their answers private. Students can easily hold the clicker in one hand and block their neighbor’s view. “We suspect that anonymity is a benefit, but right now that is really just speculation," Reay said.

Students Who Use 'Clickers' Score Better On Physics Tests

Am I reading this right?

There was a tremendous gain for female students and essentially no gain for male students? (Of course, I don't know what 1/10th of a point amounts to.)

This seems strange.

Is this a common outcome in college physics courses?:

During the 2006-2007 academic year, the clicker classes outperformed the non-clicker classes by an average of 10 percent -- a full letter grade -- on the multiple choice part of their final exams. The non-clicker class averaged a score of 61 percent on this section; the clicker class averaged 72 percent.

Wednesday, July 23, 2008

Teacher's Union Opposes Salary Increases

In Washington D.C. a strange thing is happening. A proposal to improve the educational cesspool that is the public school system in the Nation's Capital is being torpedoed by the national teachers unions (despite support from the local union leaders and teachers).

I haven't seen the story reported in any US newspapers, and I wonder why not, since I read education columns quite regularly. If I were any more cynical than I already am, I might think there is a plot by the national unions to keep this particular proposal quiet. Or perhaps I just missed the US press stories due to summer vacations and what not. Anyway, the British news weekly, The Economist, had a short story two weeks ago.

The story begins with a typical indictment of the District's schools -- hugely inefficient, extremely high cost, abysmal test scores, and outrageous student behavior. And then the teachers:
Teachers are virtually unsackable and paid by seniority. Such incentives attract the lazy and mediocre and repel the talented or diligent.
But here's where it gets interesting, the solution is somewhat novel in education reform:

Ms Rhee [Michelle Rhee, School Chancellor] is thrashing out a deal with union leaders that would raise teachers’ wages dramatically. Starting salaries would leap from about $40,000 to $78,000, and wages for the best performers would double to about $130,000 a year. In return, teachers would lose tenure and be paid according to merit, measured in part by their students’ results. Current teachers would have a choice: they could join the new system or stay in the old one. New hires would have to join the new system. Over time, the quality and morale of teachers in Washington should soar. “Imagine the kind of talent the hard-pressed system could attract,” drools the Washington Post.

But wouldn’t all this require a huge expansion of the school budget? Perhaps not. The current system is staggeringly inefficient. The city employs an army of educational bureaucrats and has twice as many schools as it needs. It pays to heat and air-condition some schools that are only a quarter full. Insiders reckon that, within a few years, the new pay deal could be wholly financed by cutting waste. And in the short term private donors are willing to shoulder much of the cost.

The plan’s boosters call it revolutionary, in that it applies to public schools a principle—reward good work and you get more of it—that every other employer has known for centuries. But it will be still-born if the Washington teachers’ union does not agree to it. Local union leaders rather like the idea of higher pay, but the big national unions are appalled at the notion that any teachers might give up tenure. Fearing an unwelcome precedent, they are leaning on the local union to kill the deal.

I can imagine the union drooling all over the pay hikes, but like most behemoth bureaucracies, they'd like the cake too, please. Big pay hikes, no accountability, lifetime tenure. Still, it is disheartening to see the difficulty the District is having getting this approved. If merit pay is a nonstarter in a district performing as badly as Washington D.C., what hope have we in a nominally high performing suburb?

Tuesday, July 22, 2008

Summarizing, Paraphrasing, Retelling

Emily Kissner's book, unfortunately, is part of my great unread. One of these days...

Still, I've read enough of it to recommend it.

The introduction & second chapters are online:

I started teaching language arts at the height of the whole language movement. The supervisor in my district had removed the old scope and sequence, drill and kill–based curriculum in favor of a far more open curriculum that allowed teachers to plan their own lessons and make their own judgments. “But I have no judgment!” I remember wailing to my mother, also a teacher. [note: this is exactly the way I felt when I first had kids and read advice books telling me to "trust my instincts": I didn't have any instincts] “How do you think I learned what to do?” she asked, and showed me her bookshelf, which was covered with stacks and stacks of professional books. I got the message. I couldn’t expect to make it through a career of teaching with only the knowledge I had picked up in a handful of undergraduate courses. If I was going to be successful, I needed to read. And read. And read.

During the next few years, I amassed my own collection of books. When I came to a thorny patch in my instruction—for example, how to get students to apply grammar skills to their writing—I would look through the books for ideas and solutions. If I didn’t find the answer in my own books, I would borrow from my mother’s bookshelf or the reading specialist’s....

This helped me to cope with the changes that swept through my classroom during the course of the next seven years. I started teaching seventh grade writing, then added sixth grade writing to the mix. When Integrated Language Arts came to our school a few years later, I was thrilled to be able to teach a ninety-minute block of reading and writing. Our state outcomes became content standards, our state testing program was transformed from performance-based assessment to “selected response,” or multiple choice, and the district middle school reading and writing department was headed by three different supervisors who dispersed three different curriculum manuals. As if these changes were not enough, I uprooted myself after seven years and went to teach a self-contained sixth grade class in a tiny rural district. Moving from a district with 28,000 students to a district with 1,800 was quite a culture shock.....

The more things changed, the more I could see how some things remained the same. Whether I was teaching to outcomes or standards, whether my curriculum was organized according to theme or genre, whether I had a classroom with windows, I faced young adolescents every day. All the books in the world cannot prepare a teacher for what happens once the students walk into the room.

I certainly wasn’t prepared to teach summarizing. Included as a content standard and an assessment anchor, I knew that summarizing was important, and I dutifully tried to help my sixth and seventh graders write summaries of both fiction and nonfiction texts. I envisioned smoothly written short pieces, like those in TV Guide, that would elegantly capture the essence of a text with a minimum of words.

What I got were stacks of bizarre constructions that claimed to be summaries—or “sumeries,” as my students often wrote—that either copied whole sentences of text, focused on just one section, or missed the main points altogether. Sometimes I wondered if the students had read the same text that I had. The more able students could occasionally pull together a coherent comment or two, but often they would try to jam a summary into the traditional paragraph template—topic sentence, supporting details, concluding sentence.

I learned many things from the article. How tomb robbers took things from tombs, what they stole from tombs, and what they were like. It was a great article.

I wasn’t sure of how to help them. My usual comments—“Elaborate. Add more. Give more detail”—are not helpful for summarizing. The students thought I had become temporarily insane when I told them, “That’s too long. Make it short. Are those details necessary?”

Standing in front of the classroom with a student summary on the overhead projector, I struggled to explain to the students why it was not effective.

“But the article is about trees, right?” Patrick asked from the front row. “So why can’t I say, ‘This article is about trees?’”

I floundered. As the teacher, I was supposed to know these things!

“It’s not good writing,” I said, finally.

“It sounds good to me,” Patrick said, to a chorus of agreement from elsewhere in the room. “I think it’s fine.”

Chapter 2 is droll:
The scene was grim. Eight of us were packed into a cramped, unair-conditioned room, spending the first week of our summer in a kind of curricular sweatshop. Our task was daunting: to unite the previously divided middle school reading and writing programs into one cohesive class. And write 100 days of curriculum in one week, using enough detail so that reading teachers could confidently teach the writing components and writing teachers could teach the reading. The sixth grade table had rapidly devolved into a bizarre reading–writing turf war.

“I don’t think retelling is something we want to assess in middle school,” a reading specialist said. “I mean, just being able to spit back* the characters and plot of a story doesn’t show any higher level thinking.” To those of us who had taught writing, she said, patronizingly, “One of the goals of teaching reading is to get kids to think critically.”


“Are you talking about retelling or summarizing?” asked a veteran teacher.

“Aren’t they both the same thing?” someone else asked. [shoot me]

“If we include retelling—or summarizing—would it be a reading activity or a writing activity?”

“How would we assess it?”

“Well,” said one teacher, who came from the more affluent part of the district, “I don’t think summarizing is a skill that we should have to teach in middle school. It’s time that we stop babying students and expect them to use what they learned in elementary school.”**

“Or should have learned,” someone else chimed in. Reading teachers and writing teachers united momentarily to agree that students should have already learned basically everything before arriving in middle school.

I’ve found that there’s no way to win one of these arguments. [ditto!] In this case, nothing I could have said would have convinced any of these teachers that they were wrong. (Despite the fact that I was the only one who had actually taught reading and writing together, I was still considered a “writing” teacher, and therefore unable to comprehend reading issues!) This group perpetuated four pervasive myths about the related skills of summarizing, paraphrasing, and retelling.

what is a summary, anyway?
If paraphrasing is just restating ideas, and a retelling is completely oral, what is a summary? This question has plagued researchers—and students— for years. Definitions for a summary abound. It may be most useful to study some of the important characteristics of a summary. Although there are some issues still up for debate, most people agree on the following points.

A summary should be shorter than the original text. How much shorter? It depends. A fifteen-page article could be summarized in one page, two pages, or even a single paragraph, depending on the purpose of the summary and the needs of the audience. A summary should include the main ideas of the text. Although this sounds easy enough, it’s where most students, and most adults, have trouble. Stating the main ideas of a text is easy when the author comes out and states them. The task becomes much more difficult when the main ideas are implicit, or unstated, as is usually the case in fiction.

A summary should reflect the structure and order of the original text. This can become another stumbling block. Fiction text written in chronological order is easiest for students to summarize. When it comes to nonfiction, however, authors use a variety of structures. Most students are used to the form of text that states a main point and then supports that point with details. (That’s the structure I’ve used in most of this book.) However, if a text is written in compareand- contrast order, the summary should follow suit.

A summary should include important details. “But how do I know which details are important?” students ask, and research shows that adolescents don’t always agree with adults on the importance of specific ideas (Garner et al. 1989). But summaries do need to include the details that support an author’s main points. A summary, therefore, is a shortened version of an original text, stating the main ideas and important details of the text with the same text structure and order of the original. It had taken me time, but I could finally lay the myths of summarizing to rest. I knew what summarizing was, how paraphrasing was completely different, and why a retelling and a summary could never be confused. Unfortunately, I didn’t learn these things in time for curriculum writing.

The argument at the sixth grade table evaporated as our supervisor came over. “Everything going well?” he asked, and all at the table smiled and nodded.

“You know,” said the reading specialist, after he left, “we only have to write 100 days worth of lessons. We could always leave it up to the individual teachers whether or not to teach summarizing.”

Another teacher nodded. “That way, those of us with—uh, more advanced kids—can move on to lessons that will really benefit them.” She looked pointedly at me.

“Besides,” someone else said, “if we were going to have summarizing tasks, we’d need to have anchor papers, rubrics, assessments—it’s just too much work.”

And there you have it: a window onto the world of our public schools, where educators decide not to teach the stuff they agree kids have to know because somebody else already should have taught it.

Not my problem.

I had never thought about summaries reflecting the structure of the original text.

I find that interesting, helpful, and intriguing.

* Which is better? spit or regurgitate?

** Note: this teacher comes from "the more affluent part of the district."

SAT/ACT Math and Beyond

Vicky S sent me notice of a workbook Stephen Wilson has posted on his web site: SAT/ACT Math and Beyond: Problems Book by Qishen Huang.

The book is listed here. I've just ordered the solution manual, which Dr. Huang says is highly detailed (460 pages for the manual, 131 for the workbook). That's critical for those of us teaching ourselves, and not easy to find.

Dr. Huang estimates that 20% of Chinese high school graduates can work 90% of these problems, which he says are not as difficult as those on China's SAT equivalent.

And...on the subject of workbooks, I've emailed Myrtle, who is using the NEM Workbooks (New Elementary Mathematics Syllabus D 1 and New Elementary Mathematics Syllabus D 2).

Meanwhile, I have done no math at all this summer, because I am busy reading C's massive Summer Assignment list, all 2549 pages of it. As to that, please know that you are in the presence of a woman who has read every last word of Guns, Germs, & Steel. There are few amongst us who can say the same.

Monday, July 21, 2008

human capital & Two Million Minutes

We watched Two Million Minutes last night. It was a lot of fun, although I don't think it works well as piece of political or persuasive filmmaking.

After we saw it, I discovered that one of the economists interviewed -- Richard Freeman -- published a book called The Overeducated American in 1976, the point at which income inequality was lowest in the country's history, which meant that the return to a college education was also the lowest in the country's history.

Gary Becker mentions the book in his essay on human capital:

To most people capital means a bank account, a hundred shares of IBM stock, assembly lines, or steel plants in the Chicago area. These are all forms of capital in the sense that they are assets that yield income and other useful outputs over long periods of time.

But these tangible forms of capital are not the only ones. Schooling, a computer training course, expenditures of medical care, and lectures on the virtues of punctuality and honesty also are capital. That is because they raise earnings, improve health, or add to a person's good habits over much of his lifetime. Therefore, economists regard expenditures on education, training, medical care, and so on as investments in human capital. They are called human capital because people cannot be separated from their knowledge, skills, health, or values in the way they can be separated from their financial and physical assets.

Education and training are the most important investments in human capital. Many studies have shown that high school and college education in the United States greatly raise a person's income, even after netting out direct and indirect costs of schooling, and even after adjusting for the fact that people with more education tend to have higher IQs and better-educated and richer parents. Similar evidence is now available for many years from over a hundred countries with different cultures and economic systems. The earnings of more educated people are almost always well above average, although the gains are generally larger in less developed countries.

Consider the differences in average earnings between college and high school graduates in the United States during the past fifty years. Until the early sixties college graduates earned about 45 percent more than high school graduates. In the sixties this premium from college education shot up to almost 60 percent, but it fell back in the seventies to under 50 percent. The fall during the seventies led some economists and the media to worry about "overeducated Americans." Indeed, in 1976 Harvard economist Richard Freeman wrote a book titled The Overeducated American. This sharp fall in the return to investments in human capital put the concept of human capital itself into some disrepute. Among other things it caused doubt about whether education and training really do raise productivity or simply provide signals ("credentials") about talents and abilities.

But the monetary gains from a college education rose sharply again during the eighties, to the highest level in the past fifty years. Economists Kevin M. Murphy and Finis Welch have shown that the premium on getting a college education in the eighties was over 65 percent. Lawyers, accountants, engineers, and many other professionals experienced especially rapid advances in earnings. The earnings advantage of high school graduates over high school dropouts has also greatly increased. Talk about overeducated Americans has vanished, and it has been replaced by concern once more about whether the United States provides adequate quality and quantity of education and other training.

This concern is justified. Real wage rates of young high school dropouts have fallen by more than 25 percent since the early seventies, a truly remarkable decline. Whether because of school problems, family instability, or other factors, young people without a college or a full high school education are not being adequately prepared for work in modern economies.


The enormous influence of the family would seem to imply a very close relation between the earnings, education, and occupations of parents and children. Therefore, it is rather surprising that the positive relation between the earnings of parents and children is not strong...

The old adage of "from shirtsleeves to shirtsleeves in three generations" is no myth; the earnings of grandsons and grandparents are hardly related. Apparently, the opportunities provided by a modern economy, along with extensive public support of education, enable the majority of those who come from lower-income backgrounds to do reasonably well in the labor market. The same opportunities that foster upward mobility for the poor create an equal amount of downward mobility for those higher up on the income ladder.


New technological advances clearly are of little value to countries that have very few skilled workers who know how to use them. Economic growth closely depends on the synergies between new knowledge and human capital, which is why large increases in education and training have accompanied major advances in technological knowledge in all countries that have achieved significant economic growth.

The outstanding economic records of Japan, Taiwan, and other Asian economies in recent decades dramatically illustrate the importance of human capital to growth. Lacking natural resources—they import almost all their energy, for example—and facing discrimination against their exports by the West, these so-called Asian tigers grew rapidly by relying on a well-trained, educated, hardworking, and conscientious labor force that makes excellent use of modern technologies.

I hate to even think about people who listened to pundits back in the 70s saying a college education was a waste of time because college graduates didn't make any money. That viewpoint was everywhere.

You have to take advice about how it doesn't pay to go to Harvard with a grain of salt when it comes from people who went to Harvard.

"gift of time" in the NY Sun

The Sun had a front page article on the "lengthening childhood" study this morning:

The "lengthening of childhood" is having grim effects on American academic achievement.

That's the message of a new paper by Harvard researchers, who warn that there is a downside to the increasingly common practice of waiting until children are 6 to enroll them in kindergarten.

Known as "redshirting," after the practice of letting college football stars take a year off so that they can start playing for the varsity a year older, bigger, and stronger, the practice is widespread: A parent decides to hold a child back a year before beginning kindergarten, and suddenly kindergartners are taller and faster and first-graders are more literate. Manhattan private schools call the extra year "the gift of time."

The practice has grown substantially: In 1968, 96% of 6-year-olds were enrolled in first grade or above. In 2005, the number had fallen to 84%, according to the paper by the Harvard researchers, part of a series issued by the National Bureau of Economic Research.

Not only are children being held back on an individual basis by ambitious parents hoping to give them a leg up; public schools from Maryland to Arkansas are following suit by legislating that children be older when they enter kindergarten.


Even private school children suffer from "redshirting," the paper argues. Though they are at a very low risk of dropping out of high school, entering school a year late means losing one year of work experience and salary.

It also means one fewer year that the children, once they are adults in the workforce, will pay into America's Social Security system.


In New York City, children must be enrolled in public school kindergarten if they turn 5 years old by December 31. For the city's private schools, the deadline is September 1. Yet private school administrators and admissions advisers said that Manhattan schools often will not accept a child younger than six. They said the schools are hoping to give students a boost in maturity before starting their formal education.

According to the paper, titled "The Lengthening of Childhood," states have followed parents in pushing up the average age of kindergartners.

In the last 30 years, nearly half of all states have increased the age at which a child can legally enter kindergarten. Maryland and Arkansas have both moved their cutoff dates to September 1 and there is currently a bill in the New York State Assembly to do the same.

Ms. Dynarski said there are several reasons why public schools might be starting children in school at an older age.

One is that high-stakes testing and No Child Left Behind have put pressure on states to drive exam scores higher. When policy makers notice that redshirted children get higher test scores, they propose that their states move the cutoff dates to earlier in the year — usually to September 1.

"The older kids do better," Ms. Dynarski said. "That doesn't mean that the kids doing better are doing so because they entered later. That might be misleading to policy makers."


"If you have a summer birthday, private schools will frequently say you're too young, you need to wait a year," the president of the private school admissions firm Abacus Educational Consulting, Emily Glickman, said.

The headmaster at Grace Church School in Greenwich Village, George Davison, estimated that more than a third of his first-graders are 7 years old. He said the older ages are a deliberate choice, made to ensure that the children are "happier and healthier."


"Sometimes, developmentally, it makes sense for them to wait a year, particularly for boys," she said. "You're never doing a bad thing by waiting a year."

'Lengthening Childhood' Has A Downside, Study Says
by ANNA PHILLIPS, Special to the Sun | July 21, 2008

The problem here is that we fit the kids to the schools, instead of fitting the schools to the kids.

Somehow, Siegfried Engelmann was able to teach academic content to pre-schoolers without a lot of hoopla about maturity and scores and whatnot.

We need a science of teaching & we need it fast.

education & mortality (& being the parent of an autistic child)

Prior research has uncovered a large and positive correlation between education and health. This paper examines whether education has a causal impact on health.


This paper has shown that there is a large causal effect of education on mortality. While GLS estimates suggest that an additional year of education lowers the probability of dying in the next 10 years by approximately 1.3 percentage points, my results ... show that the effect is perhaps much larger: at least 3.6 percentage points. Moreover there is a direct effect of compulsory schooling laws on mortality during adulthood: one more year of compulsory schooling decreased mortality after age 35 by about 3%.


To better understand the impact of education, I calculate how this effect translates into life expectancy gains. I find that in 1960, one more year of education increased life expectancy at age 35 by as much as 1.7 years (using the OLS estimate). This is a very large increase.


This evidence that education increases life expectancy implies that the returns to education, measured only in terms of earnings increases, substantially underestimate the true returns to education.

The Relationship Between Education and Adult Mortality in the United States
Adriana Lleras-Muney
January 2004

Reading The Race Between Education and Technology has led me to think about the relationship between education and being the parent of autistic kids.

Jimmy is 21. When he was diagnosed, no one knew anything about using meds in autism, and everyone was against it. Parents were horrified by the idea, and psychiatrists in Los Angeles routinely told us there were no medications that could treat the "core symptoms" of autism. I remember going to all the parent meetings & hearing that: can't treat the core symptoms of autism.

One shrink in particular ticked me off. I heard him speak in someone's living room. There was nothing medicine could do, he said confidently; the core symptoms were untreatable. News flash.

I didn't like him. I didn't like the cowboy boots he was wearing, I didn't like his twitchy manner, and I didn't like the way he slouched in his chair. I especially didn't like his air of certainty, and I was appalled by the fact that he appeared to consider himself cool. If you're going to tell me there's no hope, don't be cool while you're doing it.

How did this "core symptoms" business make sense, anyway, I wanted to know. Granting that severe mood swings and 4-hour tantrums aren't core symptoms of autism, wouldn't it be a good thing for a child not to have 4-hour tantrums?

Ditto for being unable to sleep more than 4 to 8 hours a night at an age where other kids sleep 12. Yes, sure, raging insomnia isn't a core symptom of autism, but so what? Is raging insomnia good for a 4-year old with autism?

Amazingly, I once had a doctor tell me that raging insomnia was perfectly fine for autistic kids. "These children don't need a lot of sleep," he said.

I thought that was a crock.

I was right. I was so right that in 4 years' time the twitchy psychiatrist in the cowboy boots, who had become Jimmy's doctor when our insurance stopped covering the Encino psychiatrist we'd been seeing, did a fantastic job treating Jimmy with meds.

His one truly brilliant move, when we came to his office panicked because a year of Risperdal-created peace was unraveling, was to say to us, "I'm all out of tricks, my black bag is empty. But sometimes just getting more sleep can help."

He prescribed trazodone and Jimmy had a breakthrough: in mood, in behavior, in functioning. And in sleep. Sometimes a twitchy guy wearing cowboy boots is your kid's future best friend.

That was our second medical breakthrough.

Our first had come the year before, when I was pregnant with the twins and Ivar Lovaas had told Ed we needed to place Jimmy outside the home. Jimmy was 7 years old. "You're going to have two other children to think of," Ivar said. "You have to consider your whole family." He wasn't alone in this view. Jimmy's school principal dropped broad hints that the time had come, and our SPED attorney asked if we wanted to request a residential school.

My therapist asked me, point blank, "How would you feel if Jimmy killed one of the babies?"

"Jimmy isn't going to kill one of the babies," I said. When I left her office, I called my best friend from the pay phone in the hall. "Are my friends saying Jimmy will hurt the babies?" I asked. "Are you all afraid to tell me?"

Her voice was so gentle and kind when she answered. I get tears in my eyes writing this now.

"No," she said. "No one is saying that. Everyone is incredibly worried how you're going to manage Jimmy and two babies. But no one is saying Jimmy will hurt the babies."

I never spoke to my therapist again.

Things got worse before they got better. The Northridge earthquake happened in February just after we'd begun construction on an extra bedroom; the house was a shambles and we had construction workers everywhere -- construction workers who were feuding with each other on site, to boot. The pregnancy had been high risk to start and within a few months most of the bad things that can happen to a high-risk pregnancy did happen. By the end of the 29th week I was in labor and in the hospital mainlining magnesium sulfate. We were facing the possibility of having three disabled children to care for instead of just Jimmy.

We had one person left to turn to. Our doctor, the one in Encino.

That doctor had told us there was a new drug for schizophrenia coming on the market that he wanted to try with Jimmy. Risperdal. It was different from the old antipsychotics, he said. By the time Ed saw him again, with me in the hospital and Jimmy out of control at home, Risperdal was available and the sales reps had made their rounds. Our doctor ransacked his office, pulling out every sample packet he could find and handing them to Ed, who stuffed his pockets full and carried the rest out in his hands. He drove straight to Osco's to fill the prescription before going home to Jimmy and my mother.

The Risperdal worked. With his first dose, Jimmy calmed, the tantrums dropped to nothing, and for the first time in his life he had a bedtime. Ed could read him a story and tuck him in bed and he stayed there and he slept.

Later on I told this story to one of the founders of the National Alliance for Autism Research, who was himself a psychiatrist and the father of an autistic child. He frowned and looked puzzled for a moment, then said, "Jimmy had to have been one of the first children in the country to take Risperdal."

He was.

Risperdal is a tough drug to take; it's nothing to fool around with. It is also a miracle drug, or was for us. On October 6, 2006 it became the first drug to be approved for the treatment of "irritability associated with autism." I believe that Risperdal, along with the other atypical antipsychotics, has produced a new generation of young men and women Jimmy's age who are living in the community instead of in back wards, in restraints, which is where Jimmy was headed.

Claudia Goldin and Lawrence Katz's observation that educated workers are early adopters has stayed with me. With autism, Ed and I have been early adopters.

Being an early adopter in the realm of psychotropic medications administered to your 4-year old is different from being an early adopter of an iPhone. We knew no one who was using meds, and we knew many who thought we were crazy or worse.

To be an early adopter with the big things, you have to be unshakably confident in your ability to listen, read, and think. You probably have to be as confident as the shrink in the cowboy boots, who turned out to be confident for a reason: he was good at his job. He didn't know what he was talking about with the core symptoms business; that was malarkey. But he could look at a child, talk to the parents, prescribe a medication off-label, and make it work. He was an early adopter, too.

Risperdal saved Jimmy's life. When Jimmy was 4, the social worker at the Regional Center told me, "I can see that you and Jimmy have a very close relationship. But in a few years, you will come to me for a placement."

I didn't, but she wasn't wrong. Three years later, the experts in our lives agreed that it was time.

That Jimmy's life turned out so differently is a tribute to education: to the education of the psychiatrists we've worked with for nearly 20 years, to the education of the teachers and behavior analysts who taught Jimmy and us, to the education of the research scientists in their labs, and, not least, to the many years of education Ed and I had when we were young.

Being educated ourselves, we were able, often enough, to know a good idea when we heard it.

We could spot malarkey, too.

The best of hands-on, real-world, interdisciplinary, multi-media learning

Over his 38 years at Yale, Bennett carried out research in diverse fields ranging from atomic physics to computer science and acoustics...

Many of the approaches Bennett used to collect data for his projects provided much amusement to his students and colleagues. For one project, he rented a truck and filled it with equipment and a mattress and, together with his wife and dog, set out to measure the "Fifth Force" at a site where a large body of water changed height rapidly. The site he chose was the locks on the Snake River in Washington, which gave him special dispensation to camp there with his truck for the summer.

He was also frequently seen at various sites around the Yale campus collecting data for his popular course on "The Computer as a Research Tool." For this course he was named one of the 10 best professors at Yale for many years in a row. His lectures in that course were multi-media events and included demonstrations of firestorms, removal of warts by laser, calculations of how long it would take monkeys sitting at the typewriter to produce phrases recognized from great works of literature, and comparisons of the sound waveforms of the French horn and the garden hose.

One time the professor was spotted dressed in scuba gear and pushing scales and other gadgets at the bottom of the Yale swimming pool, measuring drag coefficients.

...He used his expertise in physics and sound to make calculations on how to decrease the noise levels in the Yale dining halls and used those successfully to improve the ability to converse and to enjoy chamber music concerts there. He also measured magnetic fields around campus and around New Haven. With the magnetic field data, he showed that it was improbable that those fields could cause cancer.
(Cross-posted at Out in Left Field).

Sunday, July 20, 2008

relative age effects - references

from The Lengthening of Childhood
David Deming
Susan Dynarski
Working Paper 14124
June 2008

Angrist, Joshua D., and Alan B. Krueger. 1991. “Does Compulsory School Attendance Affect Schooling and Earnings?" (pdf file) Quarterly Journal of Economics, 106(4): 979–1014.

Angrist, Joshua D., and Alan B. Krueger. 1992. “The Effect of Age at School Entry on Educational Attainment: An Application of Instrumental Variables with Moments from Two Samples.” Journal of the American Statistical Association, 87(418): 328–36. (pdf file)

Ari├Ęs, Philippe. 1962. Centuries of Childhood. New York: Random House.

Barnsley, R. H., and A. H. Thompson. 1988. Birthdate and Success in Minor Hockey: The Key to the NHL. Canadian Journal of Behavioral Science, 20(2): 167–76.

Barnsley, R. H., A. H. Thompson, and P. E. Barnsley. 1985. Hockey Success and Birthdate: The Relative Age Effect. Journal of the Canadian Association for Health, Physical Education, and Recreation, November–December, pp. 23–28.

Bedard, Kelly, and Elizabeth Dhuey. 2006. “The Persistence of Early Childhood Maturity: International Evidence of Long-Run Age Effects.” Quarterly Journal of Economics, 121(4):

Bedard, Kelly, and Elizabeth Dhuey. 2007. “Is September Better than January? The Effect of Minimum School Entry Age Laws on Skill Accumulation.” (pdf file)

Black, Sandra, Paul Devereaux, and Kjell Salvanes. 2008. “Too Young to Leave the Nest? The Effects of School Starting Age.” NBER Working Paper 13969.

Bracey, Gerald. 1989. “Age and Achievement.” Phi Delta Kappan, 70(9): 732.

Card, David, and Thomas Lemieux. 2001. “Dropout and Enrollment Trends in the Postwar Period: What Went Wrong in the 1970s?” In Risky Behavior among Youths: An Economic Analysis, ed. Jonathan Gruber, chap. 9. Chicago: University of Chicago Press.

Cascio, Elizabeth. 2005. “School Progression and the Grade Distribution of Students: Evidence from the Current Population Survey.” IZA Discussion Paper 1747.

Cascio, Elizabeth, and Diane Schanzenbach. 2007. “First in the Class? Age and the Education Production Function.” NBER Working Paper 13663.

College Board. 2005. “Advanced Placement Report to the Nation.”

Crosser, Sandra. 1998. “He Has a Summer Birthday: The Kindergarten Entrance Age
.” ERIC Digest ED423079 1998-09-00. (pdf file)

Danziger, Sheldon, and Cecilia Rouse, eds. 2007. The Price of Independence: The Economics of Early Adulthood. New York: Russell Sage Foundation.

Datar, Ashlesha. 2006. “Does Delaying Kindergarten Entrance Give Children a Head Start?” Economics of Education Review, 25(1): 43–62.

Dee, Thomas. 2004. “Are There Civic Returns to Education?” Journal of Public Economics, 88(9): 1697–720.

Dhuey, Elizabeth, and Stephen Lipscomb. 2007. “Disabled or Young? Relative Age and
Special Education Diagnoses in Schools
.” (pdf file)

Dobkin, Carlos, and Fernando Ferreira. 2007. “Do School Entry Laws Affect Educational
Attainment and Labor Market Outcomes?

Elder, Todd, and Darren Lubotsky. Forthcoming. “Kindergarten Entrance Age and Children’s Achievement: Impacts of State Policies, Family Background, and Peers.” Journal of Human Resources.

Elson, John. 1989. “The Redshirt Solution.” TIME Magazine, November13.

Frederick, Carl, and Robert Hauser. 2006. “Have We Put an End to Social Promotion?
Changes in Grade Retention Rates among Children Ages 6 to 17 from 1972 to 2003
(pdf file)

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Graue, Elizabeth, and James DiPerna. 2000. “Redshirting and Early Retention: Who Gets the ‘Gift of Time’ and What are Its Outcomes?” American Educational Research Journal, 37(2): 509–34.

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Past, ed. Diane Ravitch and Maris A. Vinovskis, chap. 10. Baltimore, MA: John Hopkins
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Sunday, June 3.

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CRS Report for Congress, Order code RL31501, Congressional Research Service.


Werner, F. Helsen, Van Winckel, Jan, and Williams, Mark. "The relative age effect in youth soccer across Europe."Journal of Sports Sciences, June 2005; 23(6): 629 – 636.

Daiji Kawaguchi. The Effect of Age at School Entry on Education and Income, June 2006 ESRI Discussion Paper Series No.162, Economic and Social Research Institute Cabinet Office Tokyo, Japan. (pdf file)

redshirting & "tournament settings"

Competition between Parents

Red-shirting parents appear to believe that relative age matters for children’s performance. There is no evidence of a lasting benefit to education or earnings from being older than one’s classmates. [maybe, maybe not] There is, however, evidence of a lasting competitive advantage in sports. In Europe and the United States, children on elite youth soccer, hockey, swimming, and tennis teams are disproportionately born just after the age cutoff for those leagues—that is, they are the oldest of their peers. This early advantage persists, with 60 percent more Major League Baseball players born in August than in July, mirroring the near-universal age cutoff of July 31 in youth baseball....Relative age effects could plausibly persist in other tournament settings. Admission to the most elite colleges is a rank-order tournament, for example. We are exploring whether age effects persist in this competitive arena.


Two recent papers appear to contradict this extensive literature on the negative impact of later entry on educational attainment. Bedard and Dhuey (2006) find that those who enter later are more likely to attend a university track in British Columbia and more likely to take exams required for admission to a selective college and to attend a four-year college in the United States. Puhani and Weber (2007) (pdf file) similarly find that those who enter school later are more likely to follow the Gymnasium university-preparatory track in Germany. But these studies show no positive impact of age at school entry on years of completed education. Their results, like the research on competitive athletes, is consistent with the idea that relative age provides an advantage in rank-order tournament competitions, which characterizes admission to elite schooling tracks, selective universities, and competitive sports teams.

The Lengthening of Childhood (pdf file)
David Deming
Susan Dynarski
Working Paper 14124
June 2008

This is exactly what we're seeing here.


My district's middle school -- and, from what I hear, the high school, too -- are "tournament settings." The school creates artificial scarcity for highly valued resources (Honors courses at the high school, accelerated courses in the middle school) and the kids are on their own. I've always called it Darwinian gatekeeping, but tournament setting does nicely as well.

I don't know how things work for girls, and I don't know how things are going in other classes. What I've seen in my own kid's class, broadly speaking, is that the older kids win.

They'd almost have to, given the Harry Potter divide.

This is one of the reasons we're changing schools, as a matter of fact. C's new school isn't a tournament setting. At least, it doesn't appear to be.

relative age effect
high school leadership, wages, and relative age
redshirting kids
redshirting & tournament settings