Monday, November 25, 2013

Antibiotics: an ever evolving story

I really think that the issue of antibiotic resistance gets too little play, so I am happy to see it discussed -- even if the discussion errs on the alarmist side.  In particular, I am unclear as to why we can't rotate antibiotics, why we even imagine that antibiotic soap is a good idea, and would be interested to hear a good reason for the routine use of antibiotics in raising cattle. 

The last is the strangest -- we are subsidizing meat production by not making farmers pay for the externality of antibiotic resistance.  I have no trouble with meat consumption, but it is unclear to me that it is an ideal target for subsidy given the high energy costs of that food source. 

However, it is true that we would still have options post-antibiotics.  Alcohol, heat treatments, and, surprisingly, silver remain effective despite antibiotic resistance.  Having said that, there is no reason we couldn't be doing more to make use of these techniques and rely less on the medications to which germs become resistant with time. 

Ed reform background reading -- three from Wikipedia

I know this is rich coming from a blogger but too many people are joining in on the ed reform debate without having taken the time to learn the basics (Frank Bruni being a veritable poster child), particularly when it comes to curriculum reform and Common Core. Below I picked three topics that are important and generally well known among people who have been in the weeds of the education debate but which seldom show up in the standard coverage. If you're interested in this debate, they're worth checking out.

The first is one of the biggest education reform initiatives to predate the current era. It had striking parallels to many of the current initiatives and was often supported by almost identical rhetoric but it seems to have dropped down the memory hole.


New Math
New Mathematics or New Math was a brief, dramatic change in the way mathematics was taught in American grade schools, and to a lesser extent in European countries, during the 1960s. The name is commonly given to a set of teaching practices introduced in the U.S. shortly after the Sputnik crisis in order to boost science education and mathematical skill in the population so that the perceived intellectual threat of Soviet engineers, reputedly highly skilled mathematicians, could be met.
...
Mathematicians describe interesting objects with set-builder notation. Under the stress of Russian engineering competition, American schools began to use textbooks based on set theory. For example, the process of solving an algebraic equation required a parallel account of axioms in use for equation transformation. To develop the concept of number, non-standard numeral systems were used in exercises. Binary numbers and duodecimals were new math to the students and their parents. Teachers returning from summer school could introduce students to transformation geometry. If the school had been teaching Cramer's rule for solving linear equations, then new math may include matrix multiplication to introduce linear algebra. In any case, teachers used the function concept as a thread common to the new materials.

Philosopher and mathematician W.V. Quine wrote that the "rarefied air" of Cantorian set theory was not to be associated with the New Math. According to Quine, the New Math involved merely..."the Boolean algebra of classes, hence really the simple logic of general terms."

It was stressed that these subjects should be introduced early. The idea behind this was that if the axiomatic foundations of mathematics were introduced to children, they could easily cope with the theorems of the mathematical system later.

Other topics introduced in the New Math include modular arithmetic, algebraic inequalities, matrices, symbolic logic, Boolean algebra, and abstract algebra. Most of these topics (except algebraic inequalities) have been greatly de-emphasized or eliminated in elementary school and high school since the 1960s.

The second is a widespread though perhaps fading approach to running a business. Outside of various questionable theories of incentives, it might be the most influential set of private sector ideas in the reform movement. (For a more detailed account of the relationship, check out this article by Shawn Gude)

Scientific Management

Its development began with Frederick Winslow Taylor in the 1880s and 1890s within the manufacturing industries. Its peak of influence came in the 1910s; by the 1920s, it was still influential but had begun an era of competition and syncretism with opposing or complementary ideas.

Although scientific management as a distinct theory or school of thought was obsolete by the 1930s, most of its themes are still important parts of industrial engineering and management today. These include analysis; synthesis; logic; rationality; empiricism; work ethic; efficiency and elimination of waste; standardization of best practices; disdain for tradition preserved merely for its own sake or to protect the social status of particular workers with particular skill sets; the transformation of craft production into mass production; and knowledge transfer between workers and from workers into tools, processes, and documentation. 
Scientific management's application was contingent on a high level of managerial control over employee work practices. This necessitated a higher ratio of managerial workers to laborers than previous management methods. The great difficulty in accurately differentiating any such intelligent, detail-oriented management from mere misguided micromanagement also caused interpersonal friction between workers and managers.

The third is rather specific and it's perhaps more up-and-coming than big, but it has some powerful supporters and is already having a having a major impact, particularly in mathematics education.

Deliberate practice
Psychologist K. Anders Ericsson, a professor of Psychology at Florida State University, has been a pioneer in researching deliberate practice and what it means. According to Ericsson:

"People believe that because expert performance is qualitatively different from normal performance the expert performer must be endowed with characteristics qualitatively different from those of normal adults." "We agree that expert performance is qualitatively different from normal performance and even that expert performers have characteristics and abilities that are qualitatively different from or at least outside the range of those of normal adults. However, we deny that these differences are immutable, that is, due to innate talent. Only a few exceptions, most notably height, are genetically prescribed. Instead, we argue that the differences between expert performers and normal adults reflect a life-long period of deliberate effort to improve performance in a specific domain."

One of Ericsson's core findings is that how expert one becomes at a skill has more to do with how one practices than with merely performing a skill a large number of times. An expert breaks down the skills that are required to be expert and focuses on improving those skill chunks during practice or day-to-day activities, often paired with immediate coaching feedback. Another important feature of deliberate practice lies in continually practising a skill at more challenging levels with the intention of mastering it.[4] Deliberate practice is also discussed in the books, "Talent is Overrated," by Geoff Colvin,[5] and "The Talent Code," by Daniel Coyle,[6] among others.

Sunday, November 24, 2013

Points to Ponder

Ezra Klein:
In their ambition to simultaneously reformulate almost every major government program, Republicans have embraced an agenda of greater complexity and scope than anything Democrats now promote. An America in which the federal government can successfully run Medicaid but can’t build functional exchanges has no place for Ryan’s far-reaching reforms.
One of the advantages of simple and universal programs is that they are easy to administer.  When you have a country of 300 million people, it is not trivial to figure out who is entitled to benefits. 

Ironically, the sort of reforms where we match people more precisely to benefits are precisely the reforms that require really good government in order to work. 



Saturday, November 23, 2013

Kennedy, Camelot and the danger of myth

"I just can't see a picture of Martin Luther King without thinking, you know, that man's terrible."
Jacqueline Kennedy, speaking in the months after her husband's assassination.

Over at the Monkey Cage, there's a political science take on the anniversary of the assassination (Why so many Americans believe Kennedy assassination conspiracy theories). It makes some interesting points but I have a somewhat different take.

As we've talked about before, if there's an idea that fits in with pre-existing beliefs (particularly one which alleviates cognitive dissonance) and which is aesthetically attractive, people will tend to favor that idea over better supported but less appealing alternatives.

The Sixties are a period that inspire intensely conflicting emotions, particularly among boomers, often producing great cognitive dissonance and there is probably no more resonant myth than that of a lost golden age (with loss due to betrayal being a particularly popular variant). In the case of John F. Kennedy, the Camelot allusions started almost immediately after the assassination and Johnson was soon identified with one of the most mythic of betrayers. (The use of conspiracy theories to delegitimize presidencies is, of course, not limited to LBJ.)

The power of these loss myths obviously rely on the counterfactual leading to a happy place. (if Orpheus and Eurydice were headed for a miserable marriage, the story isn't nearly as effective.) In the case of JFK, for many Democrats and boomers (particularly boomers who had been draft eligible), this basically means the great society without the escalation in Vietnam.

As for the latter, there is certainly evidence that Kennedy was seriously considering getting out, having come to suspect that the war was a lost cause, but every president from Ike through Nixon saw Vietnam as problematic, but every administration got us in deeper. Wars have a long history of being easier to get into than out of. Add to that JFK's commitment to fighting communism (particularly in Latin America and, because nothing ever changes, Iraq) and you can see how certain historians take this position:
Patricia Limerick, a University of Colorado history professor who heads the school's Center of the American West, doubts Kennedy would have backed off from U.S. involvement in Vietnam. The policy of communist containment was too ingrained in him.

"That was one Cold Warrior, that Kennedy," Limerick said. "He gave so much momentum to Vietnam. Cold War thinking was such a powerful arranger of brain cells of people of a certain age at that time."

The domino theory — the notion that communist expansion would continue unless directly confronted — drove decisions. Even the race to the moon was a direct competition with the Soviet Union.

"So I don't know any reason to think that foreign policy would have evolved," Limerick said. "Lyndon Johnson inherited a rat's nest, and we all know who he inherited it from."
How about domestic (and extraterrestrial) policy? Kennedy had laid out an ambitious "New Frontier" agenda but outside of research the progress had struck many observers at the time as somewhat slow, particularly on the social justice side. It's not entirely clear why that would have changed. Even when it came to Apollo, Johnson had been pushing the space race as early as the late Fifties and was, if anything, more dedicated to the issue than was Kennedy.

Of course, the cause where the difference is sharpest is civil rights. While Kennedy was certainly progressive on these issues, they were not a priority. Furthermore, there was considerable emotional distance between the Kennedys and the leaders of the civil rights movement, most notably Martin Luther King who was not even invited to JFK's funeral.

By comparison:
By this time in January 1965, Johnson had already driven through Congress the most important civil rights legislation since emancipation. Now, he told King, their work was only beginning. When Congress reconvened, he intended to introduce a voting rights bill, one that would bring justice to the segregated South, creating a vast new pool of loyal Democratic voters even as it would surely alienate multitudes of whites. ''The president and the civil rights leader -- the politician and the preacher -- were bouncing ideas off each other like two old allies in a campaign strategy huddle, excited about achieving their dreams for a more just society,'' Nick Kotz writes in his narrative history of the two men's alliance. ''As always,'' he continues, ''Johnson did most of the talking. As always, King was polite and deferential to the new president. But there was a shared sense of new possibilities, new opportunities for cooperation to bring about historic change.'' This carefully etched scene serves complementary purposes. It captures Johnson and King at the apex of their collaboration, a snapshot of an optimistic peak that only magnifies the friction and tragedy to come.
The standard response to the Kennedy-King antipathy has generally been to blame J. Edgar Hoover ("Caroline Kennedy, the daughter of John and Jacqueline, said her mother's comments about King are evidence of the 'poisonous' activities Hoover was engaged in, as he ruled the FBI as his private fiefdom."), but as appealing as this is from a psychological standpoint (the "bad council" excuse is often used to alleviate cognitive dissonance), there are at least a couple of problems with this explanation.

For starters, Hoover had constructed his empire in large part by being able to sense both what presidents needed to know and wanted to hear. Here's Tim Weiner, author of "Enemies: A History of the FBI."
GROSS: So did Hoover kind of make a lifelong practice of using his wiretapping to spy on people he perceived as his enemies in government?

WEINER: Well, that's correct, but he also was very well-attuned to what presidents wanted to hear. President Eisenhower wanted to hear about the communist threat. President Johnson wanted to know about the Ku Klux Klan, and despite his lifelong predilection for opposing integration, Hoover did as the president ordered. He was very sensitive to the needs of presidents.
More importantly, Johnson had heard the same FBI reports that Kennedy had but they had no apparent effect on his attitude toward King, though they may have shaped his feeling toward Hoover. ("It's probably better to have him inside the tent pissing out, than outside the tent pissing in.")

In other words, the golden age story here assumes that Kennedy was about to change direction on the two defining issues of the decade -- Vietnam and civil rights -- and that he was going to change in the right direction (right according to the belief system of those who tend to hold most tightly to the Camelot myth). This could well have happened during a second Kennedy term. Or we could have had withdrawal from Vietnam but no Head Start, Medicare, Medicaid, or Voting Rights Act. We might have even stayed in Vietnam and lost all of those programs.

Myths of golden ages and the loss of innocence are tremendously appealing in large part because they let us avoid facing the way things really are. With all due respect to JFK (who was, in many ways a great man), maybe it's time to let this one go.

Friday, November 22, 2013

Students will little note, nor long remember what was taught here...

[Update: For more on Common Core and David Coleman check out this follow-up post, "The great pedagogical end run"]

It was just over one hundred and fifty years ago that Abraham Lincoln delivered the Gettysburg Address. That makes this story from Valerie Strauss particularly timely:

Common Core’s odd approach to teaching Gettysburg Address
Imagine learning about the Gettysburg Address without a mention of the Civil War, the Battle of Gettysburg, or why President Abraham Lincoln had traveled to Pennsylvania to make the speech. That’s the way a Common Core State Standards “exemplar for instruction” — from a company founded by three main Core authors — says it should be taught to ninth and 10th graders.

The unit — “A Close Reading of Lincoln’s Gettysburg Address“ — is designed for students to do a “close reading” of the address “with text-dependent questions” — but without historical context. Teachers are given a detailed 29-page script of how to teach the unit, with the following explanation:

The idea here is to plunge students into an independent encounter with this short text. Refrain from giving background context or substantial instructional guidance at the outset. It may make sense to notify students that the short text is thought to be difficult and they are not expected to understand it fully on a first reading — that they can expect to struggle. Some students may be frustrated, but all students need practice in doing their best to stay with something they do not initially understand. This close reading approach forces students to rely exclusively on the text instead of privileging background knowledge, and levels the playing field for all students as they seek to comprehend Lincoln’s address.

The Gettysburg Address unit can be found on the Web site of Student Achievement Partners, a nonprofit organization founded by three people described as “lead authors of the Common Core State Standards.” They are David Coleman,  now president of the College Board who worked on the English Language Arts standards; Jason Zimba, who worked on the math standards; and Susan Pimental, who worked on the ELA standards. The organization’s Linked In biography also describes the three as the “lead writers of the Common Core State Standards.”
At the risk of deviating from the standards of close reading, this requires some context. The education reform movement, like all major movements, is an alliance between different groups with different agendas. One of the less recognized of these groups is well-intentioned educators who champion certain pedagogical theories that have proven to be hard sells. (David Coleman is, in many ways, the archetypal member of this group.) The reform movement's emphasis on standardization (note the 29-page script) has given them a chance to apply these theories on a massive scale without a lot of review and despite a lot of resistance.

This resistance is a major but largely unreported source of tension between movement reformers and teachers (particularly experienced and, ironically, effective teachers) who are reluctant to scrap proven approaches for ideas that can, frankly, sound a bit flaky. More on that later.

This post continues the Common Core thread that started here. It also relates to some of my earlier comments about rutabaga cults.

Thursday, November 21, 2013

More Motley Foolishness -- Hydrogen is safe as a fuel, not as an investment

I spotted another doozy from Motley Fool. For a change, it doesn't involve Netflix or Disney, but other than that the formula is basically the same and the advice is, if anything, worse. As is often the case, the title gives you a good idea what to expect:

"Will This New Toyota Hydrogen Car Change the World?"

The story, by John Rosevear, is pretty much a retyped press release along with some standard pop science boilerplate on hydrogen fuel cells all delivered in MF's typical breathless style ("heavy bets on fuel cells — and hydrogen — as a way to power the automobiles of the future"). As always, MF is careful not to come out and say that this is the next big thing while being just as careful to downplay (or omit entirely) all the troubling facts that undercut their argument.

There's an old saying in military circles that goes "Amateurs talk strategy; Professionals talk logistics." When dealing with transportation technology, you might replace 'strategy' with 'features' and 'logistics' with 'infrastructure.' Transportation infrastructure often faces a nasty chicken/egg problem -- few people want to buy the vehicles until the infrastructure is in place and you can't get infrastructure funded until lots of people own the vehicles -- but with hydrogen fuel cell cars the problem is particularly acute. Not only is hydrogen somewhat difficult to handle, it is competing against a range of low and zero emission vehicles, all of which use well-established infrastructure. There is no county in America where you cannot get gasoline, diesel, natural gas, and electricity.

On top of that, you also have a serious concern about energy density. There simply is not that much power you can extract from a cubic foot of hydrogen, even under considerable pressure.Gasoline has excellent energy density. Diesel is even better. Batteries are constantly improving. With hydrogen, I don't see much room for improvement. Energy density isn't as much of a problem with stationary systems but if you have to carry your fuel around with you it's a big deal. The FCV has "two spun-carbon and aluminium tanks holding hydrogen gas pressurised to 700 bar (10,000psi)" for decent range. That's a solid piece of engineering by Toyota (which employs a lot of smart people) but you have to suspect that higher pressures will be very hard to come by.

I don't want to paint too grim a picture. It's possible that Toyota's FCV will lead to something major -- there could be an unexpected technological advance or a major government initiative that subsidizes both the cars and their infrastructure -- but based on current comparative functionality and infrastructure issues, this technology is very much a long shot.

More to the point, the challenges facing fuel cell vehicles are widely known and if you're reading something about investing in this sector, these challenges need to be prominently mentioned very near the top of the page. If they aren't, you need to ask yourself how much value to put on the writer's advice.

Wednesday, November 20, 2013

Pre-existing conditions

Mark Palko sent me a link to a Consumer Reports discussion of pre-ACA individual market healthcare.  It was scathing, giving examples like:
The Georgia real estate agent whose group health plan was folding and who couldn’t find replacement insurance unless it excluded coverage of her $1,700-a-month rheumatoid arthritis medication, without which she would quickly become disabled.
I think that the example above gives a good example of what makes the market in health insurance challenging.  When you link your insurance to your job, some people will inevitably lose their jobs.  These people will have paid into insurance when they were healthy but no longer have access to that plan.  Thus they have serious problems ever getting coverage.

Now this would be fine if acute risks were all that we were insuring against (like a house fire).  But we also insure against the development of a chronic condition that is expensive to treat and ongoing.  Now add in recission -- health plans checking to see if you gave perfectly accurate information only after you start claiming benefits (notice that they do not offer to return previously paid premiums as part of this process) and it is clear that the individual health plan market had some serious drawbacks.  In fact, given recission, it is unclear if people who lose inexpensive plans were actually insured in the case of a disaster. 

Now the private market solution to this set of problems is a regulated series of exchanges.  If these exchanges cannot be made to work, and even private companies seem to have trouble with doing so from time to time, the next best solution would be to expand public coverage.  What if anybody could opt-in to Medicaid?  Would that really be a disaster?  It would hurt medical wages and simultaneously expand demand, but we could compensate by expanding medical licensing to groups like Nurse Practitioners provide care to Medicaid patients.  Then private insurance is supplemental (like the UK) and these issues become a lot less concerning (because insurance reputation begins to really matter). 

These issues are worth keeping in mind as we watch this experiment unfold.   



Tuesday, November 19, 2013

2... 4... 6... 8... Time to disaggregate -- Motley Fool/Netflix Edition

[second in a thread]

Another example of why I'm uncomfortable with the quality Motley Fool's analyses, this time demonstrating a crude but common statistical misstep (or in some cases, distortion). The analyst here is MF regular Tim Beyers (not familiar enough with MF to say why it's in the third person).
Netflix offers each new Marvel show international distribution to as many as 40 million viewers worldwide. Disney can't achieve that on its own, Tim says, because it controls a limited number of channels for offering live action superhero content and ABC already airs Marvel's Agents of S.H.I.E.L.D.

History also favors the deal. More than 66% of gross receipts for Iron Man 3 came from overseas territories. Thor: The Dark World is also tracking well in foreign territories, much like its predecessor. Settling for U.S.-centric distribution would be aiming too low, Tim says.
If you've been following the Netflix story in any detail, one component of this argument will jump out immediately but anyone who works with data will probably have at least a hunch about where this is going.

The phrase "40 million viewers worldwide" raises the question, how many of those viewers are overseas? The answer is less than ten million. For comparison, here's how HBO breaks down:
As of September 2012, HBO's programming reaches approximately 30 million pay television subscribers in the United States, making it the second largest premium channel in the United States (Encore's programming reaches 35.1 million pay subscribers as of March 2013). In addition to its U.S. subscriber base, HBO also broadcasts in at least 151 countries covering approximately 114 million subscribers worldwide.
What's worse, those overseas Netflix viewers seem to be mostly in Europe, with little apparent presence in the all-important Asian market.

Perhaps there's more going on than we know about. Netflix could be on the verge of a big international expansion. For now though, Netflix is not a major international power compared to companies like Time Warner and while the new Netflix/Disney deal may turn out great for both parties, arguing that it's a good idea because you wouldn't want to be too U.S.-centric probably tells us less about the stock and more about the quality of the analysis.

Monday, November 18, 2013

More (Reluctantly Reported) Motley Foolishness

I was going to let the Motley Fool thread drop. They kept coming out with analyses and advice that I was tempted to comment on but I was afraid the comments would start to sound the same.

Recently, though, I saw a headline I couldn't resist clicking on. As a result, I found a whole new reason to worry about people basing investment decisions on MF recommendations. [still more have showed up since I wrote this. I'm afraid we have another thread coming.]

Just to review, when ABC announced  S.H.I.E.L.D., expectations were high. The Avengers had been one of the most successful movies ever and, based on the box office of the first semi-sequel, Iron Man 3, interest was showing no sign of fading. Nowhere were these expectations higher than at Motley Fool which came out with a list of reasons why  S.H.I.E.L.D might actually turn out to be bigger for Disney than the Avengers had been.

I pointed out at the time that this would have required a huge, historic hit and that none of the reasons listed in the MF post came close to supporting the claim.

Time passed and ratings rolled in.  S.H.I.E.L.D had very respectable ratings, but they fell somewhat short of expectations. More worrisome has been the trend: ratings have been slowly but steadily dropping since the debut.

Now Steve Symington, the MF contributor who provided the previously mentioned post, has posted a response to the news and it unintentionally captures a lot of what bothers me about Motley Fool, starting with the title:

"Skeptics keep panning Marvel's 'Agents of S.H.I.E.L.D.' for its seemingly lackluster overall ratings, but here are several reasons Disney couldn't be happier."

First of all, to get the obvious out of the way, Disney could and would be a lot happier with better numbers. For this show to live up to anywhere near its potential as a tentpole, It would half to be both a bigger and a demographically broader hit and it would need to generate lots of real time view.  There is no real tentpole effect for viewers watching on Hulu and delayed viewing greatly undercuts social media buzz on places like Twitter which thrives on the shared experience of simultaneous viewing.

None of this is disastrous. The numbers for the show are certainly not bad. On top of that, keeping the show around helps strengthen the relationship with Joss Whedon who has proven to be a very valuable asset to the franchise. Still, there's no way to get around the fact that, while there are bright spots, there is no major area where the show is exceeding expectations and there are a number of areas where it is falling significantly short.

Put another way, one of Disney's assets turned out to be worth less than was anticipated. There are various ways for investment councilors to handle situations where predictions prove directionally wrong. They can reassess their advice. They can argue that the adjustment is fairly small relative to the size of the company (difficult once you're on record as saying the asset could be bigger than the Avengers, but certainly valid in this case). What you never want to see is a councilor looking for reasons to justify previous positions. This is a natural response to cognitive dissonance but it's deadly for stock pickers.

The MF piece is filled with attempts at self-reassurance. Bright spots are trotted out without addressing the possibility that the market had already priced in anticipated numbers that were as good and usually better than what we've seen. Desperately upbeat language is used ("incredible staying power," "run up the score") while a negative but accurate statement like "continue to fall" prompts scare quotes.

Perhaps the most telling though, is what's not in the post. If you take a look at this post from TV by the Numbers after reading the Motley Fool piece, you'll notice a couple of interesting points. The arguments and wording are remarkably similar but one phrase that appears in the second post is nowhere to be found in the MF article:

"via press release:"

Sunday, November 17, 2013

Weekend blogging -- a few more for my to-see list (Truffaut edition)

As mentioned before, I have a long list of films of films that I should have gotten around to in college. One of these days, I should just go ahead and sign up for Hulu Plus see I can get access to the entire Criterion Collection (probably after I finish up with Netflix). On the other hand, I might actually end up seeing more if I continue catching the free-for-the-__- days selections (that time limit is an excellent motivator)

This week the freebies include a dozen by François Truffaut.







Saturday, November 16, 2013

Weekend blogging -- channeling my inner Sherlock nerd

As mentioned before, I'm a big fan of the show Sherlock, for my money the best of the myriad adaptations of the character. That said, I hadn't gone back and rewatched any of the episodes until I went online to find out when we could expect the season and came across this.
The second series concluded with "The Reichenbach Fall". Steve Thompson wrote the episode, which was directed by Toby Haynes, who had previously directed many of Moffat's Doctor Who episodes. First broadcast on 15 January 2012, the episode follows Moriarty's plot to discredit and kill Sherlock Holmes, concluding with Holmes faking his suicide as Watson looked on. It was based upon Conan Doyle's story "The Final Problem", in which Sherlock and Moriarty are presumed to have fallen to their deaths from the Reichenbach Falls in Switzerland. Moffat felt that he and co-creator Gatiss had outdone Conan Doyle in their version of Holmes' fall and Moffat added that, in that much-discussed sequence, there was still "a clue everybody's missed"
The Wikipedia article lead me to this quote from Moffat: "It's not a cheat. We've worked it out. It all makes sense."

I decided to go back and check out the rooftop sequence. I'm pretty sure I spotted the clue he was talking about (hint: it occurs very early in the scene) and I believe I've got the rest of the clues as well. I'm putting them after the break. If you feel like playing along, scroll down but be warned, it's all spoilers and nerdiness from there on.

I always feel a bit guilty, or at least apologetic, about this kind of post. God knows I've made fun of plenty of fanboys in my time. I will, however, offer a couple of defenses for this one case: first, Moffat really is inviting us to go for it; and second, one of the most appealing traits of this generation of British TV writers is the care they take not to abuse our suspension of disbelief. Once we've accepted the premise, they will make sure that everything that follows, no matter how surprising, will be believable in terms of plot and consistent in terms of character.

The first time I watch a Moffat and friends show, I simply go along with the effective drama and comedy. Later, I'll peek behind the curtain and look at the machinery, but when the story's good enough, that just adds to the fun


Friday, November 15, 2013

Common Core and the Law of Large Numbers

Common Core is a big story that needs to be addressed in depth (Valerie Strauss's column is a good place to start), but a lot of the devils are in the details and one of thee peskiest of those devils (call him the Mephistopheles of education reform) is what happens to high-sounding ideas on the way to actual classrooms.

Let's take the proposed standard that all students should understand the law of large numbers. This a wonderful goal, but before we add it to the curriculum, we need to think about the Luskin effect. Donald Luskin is the CIO for the consulting firm Trend Macrolytics. He's also a widely read columnist and commentator on financial matters. He's someone who ought to understand sampling and who thinks he understands it, but he really, really doesn't.

You will occasionally find an algebra teacher who obviously doesn't understand something like factoring trinomials, but that's rare. Finding a high school algebra teacher (or for that matter, a university math professor) who doesn't understand probability theory is not that uncommon and a sufficiently clueless explanation can be worse than letting the topic wait until college.

When I Googled common core "law of large numbers" this was the first non-video that came up:.
By (date), when given (5) problems involving interpreting results from a simulation using The Law of Large Numbers (i.e. (# of times an event happens) / (total # of trials) approaches the theoretical probability for the event as the # of trials grows large), (name) will correctly solve (4 out of 5) problems.

Example: A student rolls a fair, 6-sided die 10 times and gets the following results: 4, 2, 4, 3, 5, 6, 6, 2, 4, 6. How many times do you expect that the student will roll a 1 after 600 rolls?

Answer: P(rolling a 1) = 1/6, (1/6)*600 = 100 times
This is a terrible example though there's some ambiguity about exactly why it's so bad. If they mean 'expected' as in 'expected value' then the answer is technically correct but has nothing to do with the law of large numbers. If they mean 'expected' in the common usage sense, the answer is just wrong.

I checked few of the other links from my Google search. Lots had simulation results (which was a good first step) but I don't think I saw any that truly got the concept, at least not well enough to explain it. Better than this but not that much better.

Concepts like the law of large numbers are not deadwood -- they are important and useful and if you can actually find a way for students to master them you should do it -- but they share a common problem with jetsam like synthetic division. There is always an impetus to add them to a curriculum but little counterbalancing pressure not to waste students' time.

The announcement of a new curriculum is invariably followed by a round of hearty round of self congratulations and talk of "keeping standards high" as if adding a slide to a PowerPoint automatically made students better informed. It doesn't work that way. Adding a topic to the list simply means that students will be exposed to it, not that they will understand or master or retain it.

If we start talking about setting aside significant time to cover probability and statistics accurately and in reasonable depth and put the ideas in proper context, you have my enthusiastic support, but until then maybe we should focus on the understanding, mastery, retention of the stuff that's already in the curriculum.

Thursday, November 14, 2013

Yikes

There is a pension show-down as part of the local contract negotiations at Boeing.
Take one aspect of the Boeing showdown, the pensions. For decades Boeing has given its line workers a decent retirement benefit. It pays out about $90 a month for every year worked at the company, so that someone with 30 years of service would get $2,700 a month when they’re done at age 65.

Add Social Security to that and you’ve cobbled together a comfortable but hardly posh old age for sheet-metal workers, riveters and others who build the nation’s planes.

Boeing wants to cancel those pensions and put in much weaker 401(k) plans. There’s little doubt this will happen, sooner or later. Because if it doesn’t, Boeing can use pension-free laborers in South Carolina to do the same work.

It’s a race to the bottom. Or rather, a slog to an era when workers will be more reliant on Social Security than ever.

So what’s most galling is that Boeing’s CEO is out pushing to cut back on the nation’s retirement plan as well.

In recent years Boeing CEO Jim McNerney has headed the Business Roundtable, a lobbying group of top U.S. corporations. Earlier this year that group called for raising the eligibility age for Social Security to 70 years old, as well as crimping back on the benefits (by reducing the index of inflation used to calculate payouts.)

“We are going to need our employees to work longer just to fill the needs that we have in the work force,” said a Roundtable suit, helpfully explaining why all Americans should willingly retire later, for less.
I don't necessarily want to comment on the merits; Megan McArdle does a good job of presenting the pro-contract side and it was pretty well thought out.  So what I find odd in this constellation of issues is that traditional approaches to recruiting workers are being dismissed.  The CEO of a major companies is puzzled about how to incent workers not to retire at 65.  In my strange quadrant of the gamma sector, we have this thing called "wages" which are often linked to "benefits".  It's a strange paradox, but consenting adults gladly take on employment in exchange for the good and services that they can acquire with these "wages".   

Now it is true that wages have to be higher when the decision isn't "work or starve".  But that is probably a feature and not a bug -- we would like older adults who are less capable to have the option to retire.  There are many options for expanding the workforce.  Immigration for example, started now, would have wonderful effects in about twenty years.  There are a lot of young people who arrived as children and have grown up in the United States who might be willing to help bolster the labor reserve, if there really is this kind of epic crisis underway. 

h/t: Eric Loomis (who I initially thought might be making this up)

Wednesday, November 13, 2013

Just a quick dip of the toe in the water

One of the interesting pieces that is coming out about some of the high performance charter schools suggests that at least some of their success is due to selecting the most promising students.  These posts, from New Jersey and Arizona, is due to selecting students from higher income families (less school lunch eligible kids), less learning disabilities, and expelling problem students.  Clearly any school that engaged in these tactics would do better relative to public schools (who have a mandate to accept these students and an accountable procedure for expulsions). 

I am reminded of parents I know who had their kids "kicked out" of daycare.  The theory was a private daycare can select who will and will not be in their clientele and remove kids who do not "fit in".  And good for them -- that flexibility is a key part of private business and it can be useful to be able to focus on people your model is compatible with. 

But we should realize that this business model flies in the face of the ideas of universal schooling.  I challenge you to look at the chart on African-American male students in Northstar and not worry.  It's nearly a complete attrition over the course of the cohort's lifespan.  It seems incompatible with any strict definition of a 100% graduation rate, unless all of these children went on to transfer to and graduate from public schools.  If we value universal education as a public good and an underpinning of American prosperity then maybe we need an approach that is actually designed to do this? 

I will also note that it is a key principle of outcomes analysis that you need to look at what happens to the study drop-outs when evaluating an intervention.  After all, all of the adverse events on a drug could happen in the post-drug quitting phase.  This is not evidence of safety.  Nor is sending children who are struggling to public schools evidence that you are able to meet these children's educational needs. 

I would be shocked if Mark Palko didn't have a much more detailed analysis to follow this up. 

Tuesday, November 12, 2013

Distracted Driving

A classic case of a serious externality:
According to a new study published in Public Health Reports, the rate of distracted driving-related fatalities per 10 billion vehicle miles traveled went up from 116.1 in 2005 to 168.6 in 2010 for pedestrians and from 18.7 in 2005 to 24.6 in 2010 among bicyclists. However, distracted driving-related deaths among motorists decreased over the same time period — a trend that study authors said mirrored overall motor vehicle fatalities and may be attributed to safer vehicles. Unfortunately, cyclists and pedestrians don’t have such protection on the road. In fact, distracted drivers were 1.6 times as likely as nondistracted drivers to mortally hit a pedestrian at marked crosswalks and about three times as likely to hit a pedestrian while on a road shoulder.
Much as I am terrified by the movements of pedestrians, I do think that this statistic makes it clear that distracted driving leads problems.  Even hands free devices have had mixed success with making drivers safer while talking.

It seems a classic case where regulation would be useful.  Maybe cell phones should stop working in a moving vehicle?