A New Leaf

Granted, perhaps mine is a premature conclusion, but I feel pretty confident making it. Newspapers have to drive traffic, so they use different headlines, like “Cellphone Radiation May Cause Cancer”, though the proper headline is something boring like “No Compelling Evidence Linking Cellphone Radiation to Cancer”.

The WHO says (pdf):

The evidence was reviewed critically, and overall evaluated as being limited among users of wireless telephones for glioma and acoustic neuroma, and inadequate to draw conclusions for other types of cancers. The evidence from the occupational and environmental exposures mentioned above was similarly judged inadequate.

where “limited” means:

A positive association has been observed between exposure to the agent and cancer for which a causal interpretation is considered by the Working Group to be credible, but chance, bias or confounding could not be ruled out with reasonable confidence.

In other words, they cannot reject the hypothesis that cell phone usage does not increase the risk of cancer. Looking at summaries of the evidence does not change my mind; there is really only one study that finds a statistically significant increase in cancer risk. And if you pool it with the other data points, there is no effect at all:

Also, if you ask University of Maryland physics professor Bob Park about it, he will say:

All cancers are caused by mutant strands of DNA. Electromagnetic radiation can’t create mutant strands of DNA unless the frequency is at or higher than the blue limit of the visible spectrum the near-ultraviolet. The frequency of cell phone radiation is about 1 million times too low.

via DF and MR.

This is the kind of thing I sit around thinking about all day.

A trivial and short-lived marketing experiment? I just don’t get it. It’s not a movie, people; it’s a book.

Witness: Simon & Schuster book trailers and Knopf Doubleday’s attempts. The KD trailers are better than S&S – they have better music, and don’t try to make you think it’s a movie. Because it’s not a movie. It’s a book.

(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.

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.

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.

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.

I finally decided to spend a bit of time putting something in the main http://www.aruguladesigns.com/ page — just a link to this blog and my Linkedin profile, but so much more tasteful than the placeholder page that the web-hosting company posts there by default.

I fly to New York next week for a few days, a day in Boston, then a day or so over the weekend tacked on to spend time with my old college friends in Brooklyn. I also plan to see a production of Richard II on trapeze. My friend Nathan Cohen is doing the music, so in the worst case scenario I get to hear him play for a while. I am optimistic, however.

I ran across these interesting data today showing a range of metrics for a few dozen of the most prominent American/International schools around the world. Most of these schools are private and non-profit. A commenter hypothesized that IB diploma scores and SAT composite averages were uncorrelated. It turns out that (s)he is maybe right — the two series have a weak positive correlation, but the standard error is high, and the relationship is only significant at the 80% level.

Here’s a chart showing the relationship. This tells you that for every 1-point increase in the IB diploma scores, a school will tend to have a 21-point better SAT composite average. The standard error on that estimate is 15 (t-stat ~ 1.4; p-value ~ 0.18).

The number of data points is low, but you might interpret this weak relationship as evidence that these two programs — standardized test vs holistic multi-year curriculum — measure different sets of skills, and that colleges are wise to consider them separately.

IB vs SAT scores at international schools

A new service has appeared, called Kwedit, which allows the borrower to buy (usually virtual) goods now and pay for them by printing a barcode and paying cash at a 7-Eleven store.

The service has been adopted by a small handful of online games with target audiences in the 12-14 age group. The idea is to bypass parents, aka the keepers of the credit cards. These children can thus purchase items for their virtual pets, for example.

Now an eighth grader, on her own, can use a Kwedit Promise to buy a virtual 40-pound bag of Purina Puppy Chow. The chow exists only as a photograph of a Purina package, but FooPets instructs its users that the care and feeding of the digital pets they’ve adopted should be regarded as a serious matter. “Your FooPet is a real creature that lives online,” the company’s Web site says. It’s ontological nonsense, but the money that is paid for the pixels is certainly real.

On the one hand, kids need to learn lessons about money and credit. Perhaps if they get in over their heads, they will learn a valuable early lesson in effective money management. Better now, when there are no real consequences, than later, when they default on their mortgage. Right?

But something stinks about this, beyond the fact that 12-year-olds shouldn’t be frequenting 7-Elevens. Kids are vulnerable — they are powerfully swayed by “ontological nonsense.” (But aren’t we all?) We can’t expect them to make reasonable choices, nor can we even expect them to learn the right lesson from their errors when they make unreasonable choices.

Should corporate interests really be allowed to so directly engage minors in this way? Yes, teens can buy candy at the store on their own. But they can’t buy candy on credit. I suppose it’s legal, but there’s something wrong here I can’t put my finger on.