Cream and Charters

August 16, 2012
Posted by Jay Livingston

A couple of weeks ago, NYC schools chancellor Joel Klein was waving around test scores for all to see as irrefutable evidence that charter schools do a better job than traditional public schools. I voiced some reservations (here).

Not all poor schoolchildren are alike, and there’s good reason to expect systematic differences between charter school kids and others. The charter school kids have parents who, while they may be poor, are more involved in their education.  The traditional public schools get the kids who are left behind. The cumulative effect of this selection makes for vastly different kinds of learning environments – differences that have much more to do with kinds of parents and children than with kinds of school organization or the presence or absence of unions.

The charter cheerers like Klein deny any such effect.  (Klein is not just a championr of charters, He puts the taxpayers’ money where his mouth is. He used his position as NYC schools chancellor to give every advantage to charters – especially all four of Eve Moskowitz’s Success Network schools – sometimes at the expense of traditional public schools.)

The latest issue of Educational Policy has some research on this very topic by Yongmei Ni (Ni is too polite to call it “creaming” and uses the low-fat term “sorting.”): “The Sorting Effect of Charter Schools on Student Composition in Traditional Public Schools.” (here gated – I found it thanks to a tweet by Shankar Vedantam)

From the abstract:

the dynamic student transfers between charter schools and TPSs are analyzed through a series of hierarchical generalized linear models. The two-way transfer analysis shows that the student sorting under the charter school program tends to intensify the isolation of disadvantaged students in less effective urban schools serving a high concentration of similarly disadvantaged students. [emphasis added]

The problem has no easy solution.  The solution for the individual is clear – get your kid into the best school possible.  But for the system, this creaming solution makes the most disadvantaged schools more chaotic, more hopeless.

Screen Gems

August 15, 2012
Posted by Jay Livingston

The film is “Staten Island.”  I pushed the “Info” button on the Verizon FIOS remote to see what it was about.

I actually checked a review at MRQE to make sure that the character was not some speechless but nevertheless supercool dude.


It makes me wonder where Verizon get its little film blurbs anyway. Someone has to be writing these things. 

There are those who will wring their hands and see this as yet a further debasement of the language, a creeping illiteracy, and the end of civilization as we know it.  But surely there is some more interesting linguistic relevance.  Does it show the pervasive influence of hip-hop diction? 

Anyway, it has inspired me to begin work on my novella – a tale of an aging but blocked writer who goes to Italy.  He hangs out in the Piazza San Marco, falls in love with the youthful hip-hop culture there, and winds up freestyling in local trattorie.  The title – and I call first dibs on it – “Def in Venice.” 

Oh, Those Europeans – Supporting Single Parents

August 14, 2012

Posted by Jay Livingston 

Planet Money is airing segments on the Eurozone problems that arise when you try to have a unified economy but separate sovereign states. If a citizen of France is working in Germany, which country’s laws apply?

I hope this audio clip works, because you really need to hear the bemused bafflement of the American reporters trying to wrap their American minds around the concept of European assistance for single parents. Oh, those wacky Europeans. It’s the same kind of incredulous reaction Europeans might have in learning about, say, Florida’s gun laws.

(If the clip doesn’t work, go to Planet Money and start at that point. The relevant segment goes for about 1:22. I’ve also added an abbreviated transcript at the end of this post.)

The good old American view of welfare is that it should be provided sparingly if at all because it saps people’s industriousness. As we speak, Romney and Ryan are taking Obama to task for letting welfare recipients get off without working. (The Republicans are factually wrong about Obama, of course, but it’s the principle that’s important.) That kind of easy welfare is the way to moral and economic disaster for the individuals and the country at large. Charles Murray takes a similar view of single parenthood. If the government subsidizes single parenthood, single parenthood will increase,* and it has, bringing with it the economic and moral debasement of the White working class.

Surely, France and Germany, with their generous support of single parents, must be disaster zones. But no, they are among the strongest economies in Europe – Germany is surely the strongest. The unemployment rate in Germany is 5.4%, well below that of the US.

It is possible that support for single parents has taken the lock out wedlock, allowing mothers to escape bad marriages, and allowing pregnant women to avoid being forced into bad marriages.

(Click on the chart for a larger view.)

The proportion of children born out of wedlock has increased generally. But Germany, with its generous benefits, has seen a much lower increase than has the US. The rate in some other countries, the Netherlands or Norway, for example, has increased greatly.  (I cannot quickly find information on how support for single parents has changed in any of these countries.)  As for the impact of single-parent benefits on the economy, that requires much more complex analysis, controlling for a host of other variables. But at first glance at charts like this, the connection is hard to see.  Low-rate countries like Spain and Italy are not in such great shape economically.  And Japan, even before the current financial crisis, had experienced its economic “lost decade.” 

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 * Conservatives take a similar view of unemployment benefits, which they label “paying people not to work.”

Edited transcript.  The Planet Money reporters are Zoe Chace and Robert Smith

ZOE CHACE:  There was also this totally European but really fascinating story they told us about the French single mother.  She’s living in France and working in Germany.
ROBERT SMITH: In France, when you have a kid, as a single parent, you get help from the state till the kid turns eighteen.  In Germany though, a single mom gets state assistance until the child is [slowly, for emphasis] twenty-five years old.  That’s not even a kid any more [laughing], he’s a full adult, but that’s the way Germany works.  You get assistance till your child is 25 years old.
The legal question was whether the woman should get benefits under the French system or the German.
I, I know it’s confusing, believe me – the court thought it was confusing too –but what it boiled down to is this:  Germany is paying a French woman German money because the French law wasn’t good enough.  It didn’t provide enough benefits.
 

Charting the Climb

August 9, 2012

Posted by Jay Livingston

Isabella was the second most popular name for baby girls last year.  She had been number one for two years but was edged out by Sohpia.  Twenty-five years ago Isabella was not in the top thousand. 

How does popularity happen?  Gabriel Rossman’s new book Climbing the Charts: What Radio Airplay Tells Us about the Diffusion of Innovation offers two models.*   People’s decisions – what to name the baby, what songs to put on your station’s playlist (if your job is station programmer), what movie to go see, what style of pants to buy –  can be affected by others in the same position.  Popularity can spread seemingly on its own, affected only by the consumers themselves communicating with one another person-to-person by word of mouth.  But our decisions can also be influenced by people outside those consumer networks – the corporations or people who produce and promote the stuff they want us to pay attention to.

These outside “exogenous” forces tend to exert themselves suddenly, as when a movie studio releases its big movie on a specified date, often after a big advertising campaign.  The film does huge business in its opening week or two but adds much smaller amounts to its total box office receipts in the following weeks.   The graph of this kind of popularity is a concave curve.  Here, for example, is the first  “Twilight” movie.

Most movies are like that, but not all.  A few build their popularity by word of mouth.  The studio may do some advertising, but only after the film shows signs of having legs (“The surprise hit of the year!”).  The flow of information about the film is mostly from viewer to viewer, not from the outside. 

This diffusion path is “endogenous”; it branches out among the people who are making the choices.  The rise in popularity starts slowly – person #1 tells a few friends, then each of those people tells a few friends.  As a proportion of the entire population, each person has a relatively small number of friends.  But at some point, the growth can accelerate rapidly.  Suppose each person has five friends.  At the first stage, only six people are involved (1 + 5); stage two adds another 25, and stage three another 125, and so on.  The movie “catches on.” 

The endogenous process is like contagion, which is why the term “viral” is so appropriate for what can happen on the Internet with videos or viruses.   The graph of endogenous popularity growth has a different shape, an S-curve, like this one for “My Big Fat Greek Wedding.”

By looking at the shape of a curve, tracing how rapidly an idea or behavior spreads, you can make a much better guess as to whether you’re seeing exogenous or endogenous forces.  (I’ve thought that the title of Gabriel’s book might equally be Charting the Climb: What Graphs of Diffusion Tell Us About Who’s Picking the Hits.)

But what about names, names like Isabella?  With consumer items  – movies, songs, clothing, etc. – the manufacturers and sellers, for reasons of self-interest, try hard to exert their exogenous influence on our decisions.  But nobody makes money from baby names.  Still, those names can be subject to exogenous effects, though the outside influence is usually unintentional and brings no economic benefit.  For example, from 1931 to 1933, the first name Roosevelt jumped more than 100 places in rank. (That was in an era when the popularity of names was more stable. Now, names are more volatile. Nowadays, 50 or more boys names may jump 100 places or more in a single year.)

When the Census Bureau announced that the top names for 2011 were Jacob and Isabella, some people (including, I think, Gabriel) suspected the influence of an exogenous factor – “Twilight.”  

 I’ve made the same assumption in saying (here) that the popularity of Madison as a girl’s name – almost unknown till the mid-1980s but in the top ten for the last 15 years – has a similar cause: the movie “Splash” (an idea first suggested to me by my brother).  I speculated that the teenage girls who saw the film in 1985 remembered Madison a few years later when they started having babies. 

Are these estimates of movie influence correct? We can make a better guess at the impact of the movies (and, in the case of Twilight, books) by looking at the shape of the graphs for the names.

Isabella was on the rise well before Twilight, and the gradual slope of the curve certainly suggests an endogenous contagion.  It’s possible that Isabella’s popularity was about to level off  but then got a boost in 2005 with the first book. And it’s possible the same thing happened in 2008 with the first movie. I doubt it, but there is no way to tell.

The curve for Madison seems a bit steeper, and it does begin just after “Splash,” which opened in 1984.  Because of the scale of the graph, it’s hard to see the proportionately large changes in the early years.  There were zero Madisons in 1983, fewer than 50 the next year, but nearly 300 in 1985.  And more than double that the next year.  Still, the curve is not concave.  So it seems that while an exogenous force was responsible for Madison first emerging from the depths, her popularity then followed the endogenous pattern.  More and more people heard the name and thought it was cool.  Even so, her rise is slightly steeper than Isabella’s, as you can see in this graph with Madison moved by six years so as to match up with Isabella.

Maybe the droplets of “Splash” were touching new parents even years after the movie had left the theaters.

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* Gabriel posted a short version about these processes when he pinch hit for Megan McCardle at the Atlantic (here).