A New Leaf

For the discerning reader.

Shrines

Whenever I describe my trip to India this past spring, I tell people about visiting the Sikh temple in Delhi. It’s hard to describe in words, but this video does a nice job of summing up what is interesting about these temples: a massive free meal program to people of all faiths, the pool of water, and the pride the Sikhs take in rejecting the Hindu caste system. This is not the temple I visited, but it has many of the same features. Go read about Sikhism on wikipedia.

Written by nclinton

August 29, 2010 at 9:31 pm

Posted in Travel

The Long-Lasting Effect of Teacher Quality

A new working paper (pdf) by some prominent economists uses a unique education experiment in the 1980s in Tennessee to find that kindergarten class size and teacher experience have significant impacts on “adult outcomes” – among other things, the future earnings of the student about 25 years later.

The experiment randomly assigned kindergarten students to either small classes (~15 students) or large classes (~22 students). Most of the research performed on these data focus on test scores. The previous studies found a “fade-out effect” – the measurable test score bumps that students in small classes received in kindergarten reduced to near zero by later grades. This new study is surprising because it finds a significant effect that re-appears in adulthood. The small-class students were more likely to go to college, marry, purchase a house, contribute to a 401k, and they earned slightly more. Remember: this is kindergarten we are talking about.

Interestingly to me, the earnings bump is not very large for small classes over large classes. The “net present value” of the effect is about $11k per student. Not too shabby, but small compared to the almost $10k spent per student to reduce the class size in the first place. A much larger future earnings effect is found to be caused by teacher experience (and teacher “quality” as measured by test scores at the end of the kindergarten year). Their rough calculation shows that an extra year of teacher experience translated to roughly $62 of extra income per student per year – or a net present value of $34k for a class of 20 students. One might argue that by not giving kindergarten teachers annual raises of $34k, society is extracting a rent from these teachers – they are providing more long-run benefit than we are willing to pay them.

The other “explosive” result is that an above-average teacher is worth a lot more to society than a below-average teacher (as measured by kindergarten test scores). The 75th percentile teacher will increase the net present value of the 20 students in their class each year by $320,000 over the same class lead by a 25th percentile teacher.

Written by nclinton

August 17, 2010 at 9:56 am

Posted in Economy

Maximize Your IB Score

(For a primer on the IB diploma, see Wikipedia.)

After reading the interesting IB Statistical Analysis over at Wandering Academic, I was left with a number of unanswered questions. The post there deals mainly with the question of how distributions of scores have changed (or not changed) over the past five years, as well as pointing out that some courses have very different distributions than others. If I were a student, here is what I would want to know:

  • Which courses and subject groups yield higher scores?
  • Which extended essay subjects will maximize my chances of getting extra points?

I have answered these questions, to a certain extent, using Wandering Academic’s data. All data are aggregated 5-year historical world averages, which smooths out minor shifts in distributions over time. Only subjects in the WA dataset are included – for example, group 1 consists only of English A1. Scores for courses range from 1 to 7. Extended essays (see further below) are given grades of E (1) to A (5). Some of my numbers will differ slightly from WA’s due to rounding errors. (Also, I think the global average TOK score is incorrect in the WA dataset – according to my calculations, it is 3.24 rather than 2.76.)

Here is the full list of courses, ordered by their 5-year average scores:

Scores vary widely. Spanish B HL has an average score of 5.51, more than a point and a half higher than the average Theater SL score of 3.83. Groups 1, 2, and 3 dominate the top half of the list, and groups 4, 5, and 6 fill out the lower half.

To make this last point more clear, let’s look at things aggregated by subject group. There are six subject groups – students have to take courses from all six (actually, there’s a way to skip group 6 – more on that later) and split between HL (“higher level”) and SL (“subsidiary level”) versions. Extended essays will slot into one of the six groups, depending on the topic selected by the student.

English A1 takes the top SL and extended essay (EE) score averages, while “second language” HL courses are the highest-scoring. Group 4, experimental sciences, gets the lowest average scores across the board.

“Extra” points are interesting twist. To graduate with the IB diploma, a student has to accumulate a number of points across each of their courses. They can get up to 3 bonus or “extra” points by getting a good score in both their extended essay and the core Theory of Knowledge (TOK) class. Since the extra points are jointly determined by EE and TOK scores, as described in this matrix, I computed the expected extra points by taking the cross product of the scoring matrix and the probability matrix described by the actual distribution of scores in each group’s extended essay bucket, and TOK scores. This is a poor way to compute the expected score, actually – it assumes that the proportion of “E”-grade extended essays is the same in the group of students that get an “A” in TOK as it is in the group that gets an “E” in TOK. Obviously, this is false – they are not independent. Nevertheless, without access to the data on individual students, I guess we can consider this a more or less decent proxy for a student trying to choose which subject group to select for their extended essay, assuming they are equally interested in all subject groups.

To round out the analysis, I asked the question whether HL courses are better- or worse-scoring than SL courses (not including ab initio and Math Studies).

On the whole, HL courses score about a half-point higher than SL courses (perhaps reflecting the fact that students self-select), with the exceptions of English A1 (-0.21), History (-0.14), Biology (-0.08), and Math (-0.13). In these four subjects, it seems that the difference in difficulty of the material outweighs the self-selection effect.

Written by nclinton

August 16, 2010 at 2:04 pm

Posted in Internet

A Loyal Customer

On Friday, I reached a milestone of sorts at my local Starbucks: the barista retrieved my preferred drink without me having to ask for it. A small delight, not quite as great as asking for “the usual,” but close.

In my experience, barista-customer relationships at coffee shops evolve like so:

  1. Default: the normal interaction of ordering, receiving, and paying; small talk rare.
  2. Mutual Recognition: barista and customer recognize each other and treat one another with slightly more familiarity; occasional small talk; barista can sometimes anticipate the order, but still requires confirmation from customer.
  3. The Usual Order: barista connects usual order to customer’s face – no confirmation required; possible variation: “Which will it be today: a latte or a cappuccino?”
  4. Name Recognition: barista and customer know each other’s first names; frequent small talk.
  5. Free Stuff: barista occasionally (but regularly) declines payment from customer; in some cases, social interaction between barista and customer occurs outside the coffee shop.

Coffee shops display this unique progression for a number of reasons: the habitual nature of coffee drinking (causing regular and frequent interaction), the inexpensive nature of the product (giving baristas occasional discretion in dispensing free goods), and the fact that the interaction typically happens in the morning (pre-work) or post-work evening (creating a bond between two souls – barista and customer – commiserating over the work they both hate). Most people never get past stage 1. Reaching stage 5 requires an investment of time and energy that few are willing to risk.

Over the years, I have been both a (profligate) stage 5 barista and a stage 5 customer, each with their own benefits. As a current stage 3 customer, I enjoy a bit faster and friendlier service, but nothing of much value. Stage 5 is the key: it brings real, measurable wealth.

The funny thing is, businesses figured out the “free stuff” fetish we customers have a long time ago, especially coffee shops. They even figured out how to profit from it: it’s called price discrimination. There’s nothing sinister about this kind of discrimination. It just means that businesses use clever means to charge a higher price to people willing to pay the higher price and a lower price to people who aren’t. Case in point: the free coffee card. Buy ten drinks (and collect ten stamps) and get one free. The people willing to go through the hassle of collecting ten stamps are clearly more motivated by the free stuff fetish – so they throw us a bone.

Starbucks has a different twist on this kind of loyalty program. Their “gold card” is a stored value card. You use a credit card to load money onto it, then for each transaction you pay for using the gold card, you get a star. For every 15 stars you collect, they mail you a coupon for a free drink. The brilliance of this system is that the stored value card transactions do not incur a credit card processing fee – they literally save a dime or more every time I pay them using their silly card instead of with my Visa debit card. They also get interest income on the balance that sits in my “account” before I get around to buying coffee with it. So everybody wins: they get a loyalty program that more than pays for itself and I get free stuff every once in a while.

If you dig around in the official Starbucks annual filings, you’ll find some other interesting tidbits. For example, Starbucks made $26 million in 2009 on card values that are unlikely to be redeemed – i.e. the 25 cents left on a card that hasn’t been used in 4 years, or whatever the rule is. The rule used is, of course, “determined by management.” Twenty-six million dollars is double the amount from the previous year. (This is likely one of their “cookie jar” accounts that Starbucks management can legally manipulate to beat their target earnings numbers. That’s another post for another day.) Total “deferred revenue” (which is where Starbucks card balances show up) amount to about $389 million.

Other businesses offer similar loyalty programs. Frequent flyers of particular airlines collect points, which they can use for free flights or, increasingly, merchandise or gift cards. Even debit cards are in the on points game these days. And these points have value – they can be exchanged for valuable things, after all, much like currency. The key is that airlines can control very carefully how and when the miles can be exchanged. Whereas Starbucks simply gives you a free drink of your choice, airlines institute black-out dates during which you cannot redeem miles for travel and can change the “price” of goods at a moment’s notice.

I can’t verify the numbers in this table, but they are roughly equal to other quotes from around the interweb. They show that the total outstanding number of airline miles was over 14 trillion (that’s a “t”) back in 2005 and growing at a nice smooth exponential rate. For a standard domestic 30,000-mile ticket, 14 trillion miles represents more than 450 million free tickets.

All that loyalty is starting to look costly. These airlines are carrying a huge liability (something they owe) in the form of airline miles. They wold love to reduce it somehow other than giving out all the free tickets owed. According to United Airline’s 2009 annual report, they did just that back in 2007 – reaping $246 million by simply changing the “inactive account” limit from 36 months to 18 months (see footnote (a) on page 44). United claims a total of $4.2 billion in “Mileage Plus deferred revenue” (page 76) – basically, the value of all those miles on the books, that they someday owe their customers for being loyal. This liability is more than the total shareholder deficit of $2.8 billion. In other words, if not for the frequent flyer program, United Airlines might be worth something.

In the end, we continue to chase free stuff by paying for it. In the meantime, I get my morning coffee without lifting a finger, and feel for a moment, well, important.

Written by nclinton

August 8, 2010 at 9:29 pm

Posted in Economy, Internet

Either you join us, or we swallow you

Speaking of outlandish politicians, Wyclef Jean announced his candidacy for the presidency of Haiti.

I love Wyclef’s music. As this journalist points out, he is “not the most naturally gifted musician,” but I have always dug his zany sentimentality. See, for example, “911″. And the Kenny Rogers bits on Ecleftic.

I have a hard time imagining this translating to effective national leadership, however.

Written by nclinton

August 5, 2010 at 5:57 pm

Posted in Music, Politics

Political Satirist

Jon Gnarr, comedian and leader of Iceland’s “Best Party”, is the new mayor of Reykjavik, with promises of free towels at public swimming pools and a new polar bear exhibit at the zoo. The Best Party won 6 of the city’s 15 council seats. They needed to form a coalition, but “ruled out any party whose members had not seen all five seasons of ‘The Wire.’”

During his acceptance speech, he sought to assuage concerns that he wouldn’t take his job seriously:

No one has to be afraid of the Best Party, because it is the best party. If it wasn’t, it would be called the Worst Party or the Bad Party. We would never work with a party like that.

Written by nclinton

August 4, 2010 at 11:52 am

Posted in Politics

Advanced Methods of Enraging Monkeys

From the Christian Science Monitor comes this beautiful headline:

Monkeys hate flying squirrels, report monkey-annoyance experts

Japanese macaques will completely flip out when presented with flying squirrels, a new study in monkey-antagonism has found. The research could pave the way for advanced methods of enraging monkeys.

Via Marginal Revolution.

Written by nclinton

August 3, 2010 at 9:41 am

Posted in Internet, Science

Torture by Any Other Name Still Stinks

A Harvard student paper (via Harper’s) documents the way the NY Times, LA Times, Wall Street Journal, and USA Today talk about waterboarding – do they call it torture, or do they use “softer” language, like “enhanced interrogation techniques”?

The headline finding is that before 2002, the NY Times and LA Times almost always called waterboarding torture; after 2002, they almost never use the word “torture” to describe the practice… except if the people doing the waterboarding are not American.

Pernicious. It relates to the bru-ha-ha over the Rolling Stone article that effectively ended Stanley McChrystal’s career – worth a read if you have not yet. (On page 1: “Who’s he going to dinner with?” I ask one of his aides. “Some French minister,” the aide tells me. “It’s fucking gay.” [N - Classy.]) It appears that other journalists are lining up to criticize the Hastings piece as unfair or unprofessional, or something along those lines. Matt Taibbi, also writing for the Stone, responded:

If I’m hearing Logan correctly, what Hastings is supposed to have done in that situation is interrupt these drunken assholes and say, “Excuse me, fellas, I know we’re all having fun and all, but you’re saying things that may not be in your best interest! As a reporter, it is my duty to inform you that you may end up looking like insubordinate douche bags in front of two million Rolling Stone readers if you don’t shut your mouths this very instant!” I mean, where did Logan go to journalism school – the Burson-Marsteller agency?

But Logan goes even further that that. See, according to Logan, not only are reporters not supposed to disclose their agendas to sources at all times, but in the case of covering the military, one isn’t even supposed to have an agenda that might upset the brass! Why? Because there is an “element of trust” that you’re supposed to have when you hang around the likes of a McChrystal. You cover a war commander, he’s got to be able to trust that you’re not going to embarrass him. Otherwise, how can he possibly feel confident that the right message will get out?

Taibbi goes on to point out that the Pentagon has 27,000 employees in their PR department – almost the size of the entire State Department. They don’t need any help getting their message out.

This is the kind of thing we can’t legislate or dictate. It’s cultural, I suppose. And I’m just speculating here, but I can’t help think that people respond to this kind of subtle manipulation. Newspapers need to fix more than their distribution mechanisms and business models if they want to survive; they also need to think long and hard about their purpose and mission.

Written by nclinton

July 1, 2010 at 12:25 pm

Posted in Internet, Journalism

Found Writing 2: Confined to the Road Ahead

Another piece of found writing from my hard disk archives, this one from April 2006, a time of money and career and personal stress. I can’t say I still feel this way… in many ways my life is simpler and quieter than it was then. Anyway, there are some nice turns of phrase worth publishing.

The so-called crawl space beneath my ground-level apartment floods with water following each of Berkeley’s frequent rain showers. Other than when said flood douses the pilot light for my weird and scary floor-mounted heater, I don’t really care. Left alone, however, the building’s foundation is at risk of erosion.

The prospect of the building’s collapse concerns my landlord precisely to the extent that it is profitable for him to be concerned. Thus, instead of digging up the ground and installing the proper drainage system, he decides to employ the services of a much less expensive, yet mammoth, water pump. This machine is separated from my bedroom by not more than a few inches of wood and insulation.

“It is loud. It disturbs me,” I tell him. “How surprising! It emits only a ‘low whir’,” he replies. Actually, that “low whir” is a low B-natural hum starting and stopping at roughly hourly intervals, but randomly, like the drones of a Casio-keyboard bagpipe in an audio version of water torture.

It made me realize: what I really want in my life is some peace and quiet. No alarms and no surprises, as someone once sang (but not in the vaguely suicidal way they sang it). I want to sit and read books and then walk somewhere quietly and drink coffee and then go to sleep when my eyelids droop. I am tired of the noise of modernity, the steady beats of war drums and market tickers and engine pistons. Their rhythm chokes me. They are loud. They disturb me.

As free as I am supposed to be (Americans have so much excess freedom that we have even begun to export it), it is often difficult to turn off or shut up or slow down. I am a captive to the cycles of bills and debts and budgets, confined to the road ahead. Beyond the cycles, there are errands to run and papers to sign and meetings to attend. Freedom means having options, but the toughest one to come by is the one to choose less over more.

Nominally, I have this freedom. It’s called being a bum. But I don’t want to be a bum. I want to have means without responsibility.

On the other hand, real freedom is internal. The trick is to not worry about things outside of one’s control. Like god, for instance, or the weather, or shifts in tectonic plates, or the rate of decay of take-out pad thai.

Internal or external, the freedom I crave is to simplify, to quiet, to do or not do as I please, to turn down the volume, to breathe deeply, to sleep. I want freedom from the low whir.

Written by nclinton

June 26, 2010 at 4:03 pm

Posted in Writing

Found Writing 1: On a National Language

I’m sitting in my living room this afternoon, enjoying a perfect Berkeley afternoon, sad that Bruce and Dawn could only stay one night, and organizing my messy hard disk full of files. Here’s something I wrote in May 2006, but never published or sent to anyone, probably in response to something I saw in the news. I only vaguely recall writing it, but I think I still had law school on the brain at the time.

National identity and cultural identity are no longer congruent. There is no doubt that they were in centuries past, and that they are still in many places, but only coincidentally and usually at the expense of a minority population. This is a central consequence of the first amendment of the U.S. Constitution: that government (nation) must protect the rights of free assembly, speech, and religion (components of culture).

As such, the notion of a “national language” is only useful to the extent that it facilitates the efficient functioning of government (a famously insufficient condition, unfortunately). Note that commerce is exempt from this stipulation except where commerce and government intersect, that is, in the enforcement of contracts. Contracts themselves, however, are culturally neutral by design; a merchant need not speak english to expect that I pay him for his wares.

But what of the social contract that citizens of a nation undertake in their collective effort to coexist? I believe that it should not be subject to the imposition of a national language. Nations should make every reasonable effort to make the governing of their people independent of culture.

To that end, president bush should not insist that the national anthem be sung only in english.

Written by nclinton

June 26, 2010 at 3:53 pm

Posted in Economy, Writing

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