Friday, 31 May 2013

I Saw a Ship a Sailing

A Child's View of a Sailing Ship

I saw a ship a sailing
Sailing on the sea
And it was all laden
with pretty things for thee 

When our son was a toddler, his favourite book was an illustrated book of Mother Goose rhymes; among them was the tale of a Packet, captained by a duck. The fantastical ship in the story is "laden with pretty things."  We read the book through together so many times that it became dog-eared and the binding eventually came apart.  Even as a three-year-old, he could repeat the rhymes just by looking at the pictures.

I was thinking about this little rhyme this morning when I read the postings of an old college friend who last night went in for neurosurgery to remove a tumour from his brain.  Ben, a classmate of mine, had been on the baseball team with me at Dartmouth as well as a singer in the Dartmouth Aires, a quite competitive a cappella singing group.  Ben apparently had a seizure and was admitted to hospital, where the tumour was found.

Like Ben, I am 43 years old - not at terrible risk for mortality, but certainly entering the age where it is becoming obvious that we need to pay attention to our health if we are not already.  Personally, I took up running 20 years ago following my first wake-up call - the death of my own father from cancer.  

There is a less-than famous quote to the effect that in life, the only ship that is guaranteed to come in is a black one.  Rich and poor; famous and obscure; powerful and powerless - we all await the same fate.  

Before your ship comes, take the time to enjoy the people in your lives.  Play with your kids.  Talk with your spouse.  If there are family members with whom you are currently fighting - or worse, have fallen out of touch with - pick up the phone or knock on their doors.  Personally, I've not always lived up to my own advice; too much time at work or treating my personal relationships too casually.  We think we have all the time in the world.  In truth, the black ship is already on the seas somewhere.

As of this moment, I don't know the outcome of Ben's surgery.  He's a big, otherwise healthy guy.  He is in the care of some of the best doctors in the world.  And he's a really good guy who deserves the best outcome, so I have faith that he will come through with flying colours.  I believe that the ship coming in in this case will be the one with sails made of silk and masts made of gold.

Ben has performed in the past at Fenway Park, singing the national anthem before a game of his beloved Red Sox.  I think I and many others are looking forward to his next performance there in the very near future.

Wednesday, 15 May 2013

Fight Fiercely Harvard

Fight fiercely, Harvard!
Fight, fight, fight!
Impress them with our prowess, do.
Oh, fellows, do not let the Crimson down;,
Be of stout heart, and true.
Fight for Harvard's glorious name!
Won't it be peachy if we
Win the game? Oh goody!
Let's try not to injure them,
But fight! Fight! Fight!

In these pages, I've written about the mathematician and ersatz musical satirist Tom Lehrer ("The New Math," "Wehrner von Braun.")

Thought of Lehrer today as I read about the recent kerfuffle created by (former) Heritage Foundation scholar and Harvard PhD Jason Richwine.  Richwine was the author of a recent analysis that, among other things, roiled the ongoing immigration "reform" debate by costing out illegal immigration.  His analysis, which balanced tax receipts generated by the contributions of illegal immigrants versus the costs of social services that they add to our national ledgers, found that the proposed plan being considered today would, over the next 50 years, bring a net cost to the US government (read: the US taxpayers) of $6.3 trillion.

This of course stands in stark contrast to the rhetoric we are being sold about how reform will be a net benefit.

Of course, the debate about immigration should be much broader than a cold, dollars and cents calculation, but to ignore this reality is something done at great peril by a nation that already struggles to pay its bills.

The report, well, it just won't do, and so off went various advocacy and special interest groups to undermine it however they could, and it did not take them long to discover that Richwine had written a most politically unacceptable dissertation at Harvard, where he earned his doctorate.

Richwine's PhD thesis, it seems, was on IQ and immigration policy; the 316 page paper describes empiric differences in IQ testing between various immigrant groups, their second and third generation offspring, and the impact his has on economic and social policy.  The whole thing can be seen here.  It's long and highly mathematical, and thus not really for the statistically faint of heart.

The reaction has been, well, curious.

Richwine was promptly defenestrated from Heritage in an act of true intellectual cowardice.

Worse, the reaction at Harvard - perhaps the premier research university in this country if not the world - has been downright shameful.  Students have been in high dudgeon, questioning just how such a heretic could have been awarded a PhD, asking that the thesis committee (a solid, reputable trio of scholars) be exposed, and in fact, that steps be taken so that "this does not happen again."

I've read some of Richwine's thesis, and trolled through the stats in the Heritage report.  From a mathematical and empirical perspective, my judgment is that his mechanics are on quite solid ground.  One can quibble, of course, about the variables included, and more "controversially," the exogeneities (those variables that affect the outcome that the model by definition, cannot measure).  But Richwine's work is serious scholarship.

That's beside the point to those who demand that Richwine be placed onto a scale with a duck, lest he be a witch.

One thing curiously missing from any of the complaints I've read is any attempt to disprove the numbers Richwine presents.  And this from a group who have bleated incessantly for the past 13 years about "science."  The point seems to be that Richwine is wrong because, well, the conclusion is just not acceptable.  The math and the science be damned.

Liberal blogger Andrew Sullivan nicely summarises the hysteria in Cambridge thusly:

But what the Harvard students are saying is worse than creating a straw man. They are saying that even if it is true that there are resilient differences in IQ in broad racial groupings, such things should not be studied at Harvard because their “end result can only be furthering discrimination.” You can’t have a more explicit attack on intellectual freedom than that. They even seem to want the PhD to be withdrawn. ...
That’s my view in a nutshell. What on earth are these “liberals” so terrified of, if not the truth? ... 
But please don’t say truly stupid things like race has no biological element to it or that there is no data on racial differences in IQ (even though those differences are mild compared with overwhelming similarity). Denying empirical reality is not a good thing in any circumstance. In a university context, it is an embrace of illiberalism at its most pernicious and seductive: because its motives are good.

I don't know for a fact that there are inherent differences in ability between various ethnic groups.  Richwine could be wrong in that there are meta factors  his model mismeasures, and that ethnic origins are a proxy for the real causes of the disparities.

What is empirically undeniable is that IQ tests have shown an almost uniform difference for 50 plus years.  The "science" for these differences is at least as solidly established as climate change.  And as with climate change, pretending what is empirically obvious - in Sullivan's words, "denying empirical reality" - will not make that reality disappear.

That students at Harvard University react with such intellectual cowardice - 'EEK! A WITCH!" - does not speak highly of our top students.

Getting back to Lehrer, it seems that, when it comes to today's students in Cambridge, fighting fiercely is a thing of the past, at least so far as intellectual freedom.

If I were a Harvard student or graduate, this would fill me with a deep shame today.

Friday, 10 May 2013

5000 And Counting

This week, this humble blog celebrated its 5000th page view.  Well, 'celebrate' is a bit strong.  Still.  Viewed 5000 times; that's 10,000 eyes.  From more than a dozen countries.

Here's the current map.

Graph of most popular countries among blog viewers
Viewing Footprint Shows a Strong Norther Bias

In the past week, eyeballs from the US, Canada, the UK, Ireland, France, Germany, Russia, China, Ukraine (!), and Moldova (!!) have visited.  

I'm not sure who in Moldova blundered here - no comment was left.  Could be a robot, or someone phishing.  Thus far, I've not received any breathless requests from descendants of the deposed Romanoff family, promising riches if I send a cheque for a couple of hundred bucks.

Anyhow, viewers have also come from Mexico, Australia, Brazil, South Africa, and Vietnam.  Thus far, no princes from Nigeria.

Some fun facts:
  • This is the 114th post.  About 45 views per post
  • One post in particular - about Margaret Thatcher, was the most viewed - nearly 200 hits
  • Posts have covered topics as varied as California licence plate schemes, baseball free agency and market efficiency, Oprah Winfrey's weight, taxes, and statistical perorations.  Oh, and some politics here and there.  
  • I've now posted at least once in each of the past 5 years (2009, 2010, 2011, 2012, and now 2103).
  • Some predictions have been pretty accurate (comment on my running history in 2009 predicted I would hit 12,000 total miles run in November 2010, which I did).  
  • Some predictions have been way off (discussion of Dontrelle Willis's future)
Oh, and through it all, the Toronto Blue Jays still stink, the Stanley Cup still eludes return to Canada, and there still will be rain on that plain down in Spain...

Thursday, 9 May 2013

The "Hot Hand" - Reality or Fantasy

I don't follow the NBA really at all, but I am interested in other sports (baseball in particular) and mathematics.  Thus, I found a recent NY Times article on the phenomenon of "hot hands" in sports quite interesting.

The author, following the opening game of the Chicago Bulls - Miami Heat playoff series, commented on a recent paper analysing the question of whether such streaks exist or are just an imputed pattern amidst random outcomes.  In that game, Chicago's Nate Robinson, basically a 29-year old journeyman of no particular note, poured in 27 points (more than twice his career and seasonal averages) to lead the Bulls to a surprise win over Miami.  The Heat are heavy favourites to win this series and the title.

Underlying the article is a recent analysis done by Yaari Gur and Shmuel Eisenmann, two computational biologists at Yale University.  The two analysed data from both the NBA (free throws) and the Pro Bowlers' Association in an effort to determine whether there are any data to support the belief.

The research followed up to a 1985 paper done by Amos Tversky, a professor of statistics at Stanford, that looked at the same question, based on field goal and free throw sequences.  (NB: I knew Professor Tversky casually during my time as a graduate student at Stanford).  I read the paper 20 years ago as part of my own research into defining randomness via what is called Kolmogoroff-Chaitin Complexity.  Put as simply as I can, K-C theory looks at the level of difficulty, measured by length, needed to define a long string of data.  The longer the description, the more complex the string, and hence the more "random" it is.

In an example, consider a 10000-character string of "X".  In computer code, this can easily be described as the ASCII code for X (88) followed by the hex code for 10000 (2710).  Thus, a 10000 character string compresses to 882710, a very, very short and thus non-random string.

Tversky looked at sequences of makes and misses, and in particular, runs of each, and the likelihood, presuming that each shot is an independent event.  According to Professor Tversky's paper, mathematically, these runs are indistinguishable from random variation.

The newer research of Professor Gur approaches the problem from a slightly different angle.  Rather than looking at strings, he looked at free throw pairs/triples (in the NBA, players can be awarded three free throws if fouled on a three-point shot), and conditional probabilities of making the second/third free throw following the outcome of the first/second shot.

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Conditional Probability Plot of Free Throws from Gur, 2009
The analysis compares P(1|0) (probability that second shot is made, given that the first is a miss) vs. P(1|1) (probability that second shot is made, given that the first is made).  The results are based upon a variation of what is called a Polya Urn, named for George Polya.  Balls are drawn from an urn containing B black balls and W white balls.

The research of the second paper concludes that there is a slight (7-12%) increase of the likelihood following a make.  Thus, a 70% free-throw shooter improves to about a 72% shooter if he has made the first. It's a very small difference.

Sports is a physical and mental endeavour, as Yogi Berra attested ("90% of this game is half mental"), so this result has face validity.  Any golfer also knows that a key to a good round is to find a good swing and then just repeat it.  As a golfer of middling ability, my own anecdotal evidence is that I can have a round where my swing just "feels" right, and I can duplicate the same pattern on most of the holes.  The opposite also is true.

The same phenomenon also is perhaps demonstrated in that a free throw shooter 'feels it,' when a good stroke yields a make, and a poor shot results in a rim-shaking brick.  A missed free throw is likely, psychologically, to result in the shooter attempting to make slight adjustments.  Thus, it seems that what is really being seen is not so much a hot streak, but the avoidance of cold ones - poor shots.

Does this apply to teams?  That seems less likely to me.  Neither Tversky nor Gur looked at winning streaks for teams or "runs" (periods of time in a game where one team seems to make all of its shots and scores a large number of un-answered points).

A back-of-the-envelope analysis was done by the baseball writer Bill James back in 1986, where he looked a the probabilities that a team who lost the first game of a playoff series came back to win the second.  Adjusting for winning percentages, home/road advantage, and other variables, James concluded that the team who LOST the first game had a slightly elevated probability of winning the second, which stands astride the common wisdom about "hot streaks."  James's conjecture was that the team who lost the game was more likely to examine the events of the game and make adjustments - changing the lineup, for example - than the team who won the first game.

This lesson was lost on the NY Times author, who took the results of Gur and optimistically predicted that the Bulls, the hot hand, would walk over the Heat.  Granted that Ms. Reynolds cops to being a Bulls' fan and thus not objective, she appears to be reading into the data something not there.

Empirically, her optimism was not borne out, as Miami came back to blow out Chicago in Game 2, 115-78.

Wednesday, 8 May 2013

J. Wellington Wimpy, Economist

"I will l gladly pay you Tuesday for a hamburger today."

The famous pitch, now eight decades old, from perennial mooch Wimpy of Popeye fame. (Side Note: Wimpy apparently was based upon an admixture of two men - one called Wellington J. Reyonolds, an instructor of the cartoonist E C Segar at the Chicago Art Institute, and the other "Windy Bill" Schuchert, the manager of an opera house where Segar had worked).

Now, recalling the character of Wimpy - not too fond of work, with a voracious appetite, and an uncanny ability to hit up others for the money to obtain his favourite food - I was amused to read on this Finance site of a creation of the Economist magazine: the "Big Mac Index."

The basic idea is that the price of a Big Mac, a fairly common good that is subject to the various laws of economics - supply and demand, inferior/superior goods, income substitution theory, revealed preferences and the like, can be indexed and used for various microeconomic analyses.

In the article, the author argues that the government are using some sleight of hand in manipulating the consumer price index (CPI) as part of a grander scheme to puff up the economy despite the appearance to all those NOT employed by the US Treasury that our economy is recovering.

Peter Schiff, an economist at a firm called Euro Pacific Capital and the author of the recent book The Real Crash, is to say the least, a sceptic of claims from Washington:
According to government measures, inflation in the U.S. is all but non-existent. The officially endorsed Consumer Price Index (CPI) claims a mere 1.5% rise in prices over the 12 months ending last March. Food and energy, which are excluded from core inflation, rose 1.5% and fell 1.6% in the same release.  
Citing The Economist's Big Mac index, Schiff says real inflation has been understated since the government started adjusting the way inflation was measured in the early 2000s. Since 2002 the Big Mac has risen in price at nearly three times the rate of overall inflation.
According to Mr Schiff, this represents "more anecdotal evidence that what we get from the government when it comes to inflation is not information but propaganda."

Anyone paying even the least attention to the news by now is aware of the mania around "the sequester" and the "grand bargain" being played at by the US congress and the president.  The main baton mis dans les roues is the indexing of entitlements (e.g., Social Security) to the CPI.  The president and the Democrats are of course strongly opposed to any revisions in the way that these benefits are calculated.  It represents something of a conundrum in my view for the president.  On the one hand, we're told that running ever larger deficits is OK because inflation is currently under control - and the CPI is used for this calculation.  On the other, constraining benefits to the so-called "chained CPI" would result in a slower rate of growth of said benefits, which would in effect represent a significant cut in purchasing power for retirees and other beneficiaries as inflation erodes the value of the dollar.

Mr Schiff points out that the price of a Big Mac (in the US) closely paralleled the CPI from 1986 until 2002, and then diverged.  Since 1986, the CPI has increased about 110%, whilst the BMI has grown significantly faster (173%), with virtually all of the increase since 2002.  This is right around the time of the greatest inflection in the housing "bubble," with a brief period in the 2008-2010 implosion.  Following the election of Mr Obama, the BMI really took off.

The Historical Big Mac Index
Of course, these data don't really prove anything, but it is an interesting window into empirical impacts of fiscal policy.  We're told that the flooding of our economy with easy money has not resulted in significant inflation, and in fact, much of the current, common wisdom of Keynesian economists like Paul Krugman is that - far from being concerned about deficits - we should be continuing to print money and stimulate.

The evidence is far from dispositive, but needless to say, if we were to switch to a barter economy with Big Macs as a means of exchange, inflation would be obvious to all, including Professor Krugman.

The Economist, largely a not-at-all-silly source of news, concocted the Big Mac Index in 1986 in a somewhat tongue-in-cheek measure, somewhat like the old Pax McDonica - the artefact that no two countries who each have a McDonald's restaurant have ever gone to war - of economics.

At their site, there is a fascinating, interactive set of graphs by which people can use the price of a Big Mac for various analyses.  My favourite is its use as a measure of fiscal and currency manipulation.  For example China is currently the bête noire of the currency world.

In this simple analysis, the current price of a Big Mac in various countries is compared to the price of same in the US - its index price.  This is adjusted for purchase price parity - a measure of how much a comparable basked of products costs, adjusted for per capita GDP.

This is used as the means of empirical currency evaluation.  In essence, if a Big Mac costs $1 in the US, and RMB8 in China, then the exchange rate should be roughly 8:1.  This presumes purchase price parity, which of course is inexact; restaurant spending is somewhat positional- part of the cost includes the societal "value" one gains by being seen doing something.  The positional value of a Chevy Impala is pretty low; the relational value of an Audi, comparably higher.  Believe it or not, in China, eating in a McDonald's was seen in the past as a symbol of affluence - the consumer could afford a "modern, western" lifestyle of a sort.

The official exchange rate is then compared, and the currency either 'overvalued' or 'undervalued.'

Below is the most recent display of currency manipulation as adjudicated by the Big Mac Index.

Current State of Currency Policies
Countries who are coloured in RED are those where the currency is undervalued (i.e., is empirically worth more than the official exchange rate yields), whilst those in BLUE are overvalued.  The US, as the index, is green.

China, unsurprisingly, is one of the top places where the currency is undervalued.  A Big Mac currently goes for RMB16.00.  Using the official, current exchange rate of $1=RMB6.14, the PPP-adjusted price of a Big Mac in China is equal to $2.61 in the US.  The actual current index price of a Big Mac in the US is $4.30.  Hence, the RMB, using this rate, is undervalued by 40% ( {$4.30 - $2.61} / $4.30}).

What this means is, in a nut-shell, that if the exchange rate of the RMB to the US dollar were indexed to the cost of a Big Mac, one dollar would buy 3.22 RMB, as opposed to the 6.13 it actually does.  There is, thus, some empirical evidence that China is undervaluing its currency, at least according to the eminent economist Ronald McDonald.

Tuesday, 7 May 2013

Could it Be? Yes it Could.

The Cicada, after its Emergence (Before)

File:Cicada skin.jpg
The Famous Shell of the Cicada (After)

Something's coming; something good.

If I can wait.

Tony - the male lead from the play West Side Story appears early in the first act, singing his song of anticipation.  Of course, the something that is coming is a mixed blessing - he meets Maria at the dance, falls for her, plans to run away.

It all ends somewhat badly for Tony.

Thought of this when I read today that at any moment, those of us on the east coast will experience the re-emergence of the cicadas, after 17 years underground.  These little insects bide their time for 17 years, and then, on cue, when the ground temperature reaches 64 degrees, burrow up seeking mates.

The last appearance of this group was in 1996.

For the course of a week or so, the trees will be alive with the chattering calls of male cicadas, hoping to attract their own femmes fatales for what are truly les liaisons dangereuses.  Most will be eaten by birds, frogs, or other creatures before they can fulfil their destinies.  For the lucky few, upon finding their mates, will die soon thereafter.

Entymologists have several explanations for the reason of the periodicity.  Some believe it is due to an evolutionary mechanism to foil would-be predators.  Others believe the timing is to ensure that broods (there are different "waves" of cicadas) do not compete with one another.

I find it remarkable that these little creatures seem so perfectly designed, so patient.  Waiting for all those years for a couple of days in the sun.

All for love.

Friday, 3 May 2013

Les Grandes Personnes Ne Comprennent Jamais Rien Toutes Seules

Qu'est-ce que c'est ça?

After the passage of quite a few weeks - months, actually - finally got the word that my job assignment has cleared all of the internal hurdles.  So this summer, we will be heading off for three years in Paris, France,  At the announcement in our internal team meeting yesterday, my superior thanked me for my patience and described the process as akin to a root canal.  I remarked that it was more like giving birth, in that the process delivered a tangible result at the end after much strain, and at seven months, would have been only a slightly premature baby.

My sister-in-law, knowing somewhat ahead of time, of the news, sent our seven year old a copy of Antoine de Saint Exupéry's classic Le Petit Prince.  It's a fun story, and interestingly, one of the very first French-language books I read, about 30 or so years ago.  The story opens with the author describing his early days and the frustrations a small child feels in negotiating the adult world.

In the opening chapter, St Exupéry details how, upon reading in a book the story of a snake swallowing its meal whole, and then over the course of six months, sleeping as it digests its unfortunate prey, makes his first drawing.  Proud of his work, he shows it to the adults in his life.

J'ai alors beaucoup réfléchi sur les aventures de la jungle et, à mon tour, j'ai réussi, avec un crayon de couleur, à tracer mon premier dessin. Mon dessin numéro 1. Il était comme ça. J'ai montré mon chef d'œuvre aux grandes personnes et je leur ai demandé si mon dessin leur faisait peur. Elles m'ont répondu: "Pourquoi un chapeau ferait-il peur?"
In English (excuse my decades-old French skills)
I thought for a long time about adventures in the jungle, and then, using a coloured pencil, I made my first drawing; drawing number one.  It looked like this.  I showed my masterpiece to the adults, and asked them if my drawing frightened them.  They all responded, "Why would a hat scare me?"
St Exupéry reflected thusly, that grown ups never understand anything by themselves, and that they always need children to explain, which is difficult, tiring.  Later, he extends this thought with the reflexion that we all were young once, but very few of us remember what it was like.  

In one of my favourite quotes from the book:
Toutes les grandes personnes ont d'abord été des enfants. Mais peu d'entre elles s'en souviennent.
I'm now reading Le Petit Prince to my son, and it's interesting to hear his reactions to it.  He doesn't speak more than a few words of French, so I do my best to translate for him, and he seems to like the story.  

As we prepare for our experience in Paris, with the excitement of a new job (for me), and a new country and culture (for all of us), it will be interesting to keep this in mind.  Alastair, a small child for which much of the world is still relatively new, will have reactions to the experiences than we will.

In the story, the "hat" that big people see is, in fact, an elephant entombed within a boa constrictor.

C'est un éléphant qui se trouvé
dans un serpent boa
I hope I can keep in mind that some of what he sees will be a hat, and some will be an elephant inside a snake.

Wednesday, 1 May 2013

Why Don't You Just Try 'Acting'

There's a famous (though not sure if not apocryphal) story that surrounds the 1970's movie "Marathon Man."  Dustin Hoffman plays a grad student who discovers that a Nazi war criminal, played by Sir Laurence Olivier, is smuggling diamonds in New York.  As the story goes, Dustin Hoffman - a notorious 'method' actor - in order to enhance the perceived "realness" of a scene in which he had been awake all night running, reported to the set having actually stayed awake the night before.

Noticing how bedraggled Hoffman was, Olivier commented, "Dustin, why don't you just try acting?"

I thought of this comment upon reading this recent column of Maureen Dowd of the New York Times.  Dowd is, in my opinion, the worst columnist in this nation's newspaper of record whose name does not include "Gail" and "Collins."  As an aside - is anyone in the country more upset that Mitt Romney did not get elected than Collins?  What is she going to write about now that the "Mitt Romney put his dog on the roof of his car" trope is past its sell-by date?

In Dowd's column, she takes to task President Obama for his petulance in response to a question at the press conference marking the first 100 days of his second term.  The president was asked as to why he cannot get his agenda through the congress.  Mr Obama, in what is becoming a bit of a pattern, peevishly shot back, "If you put it that way, maybe I should just pack up and go home."  Maybe the president is looking to his adolescent children for style and substance tips.

Dowd (to give credit where it's due) points out that the president, despite his protestations, does have as part of his job the task of trying to motivate a restive, diffident congress.  The blame congress excuse is starting to wear thin.

But where Maureen Dowd falls down is in her Simple Simon suggestion that, because President Obama played Daniel Day-Lewis playing him playing Lincoln at the White House Correspondence dinner (really; Holy Victor Victoria), Mr Obama should "channel" Lincoln himself.
How can the president star in a White House Correspondents’ Association dinner satirical film pretending to be Daniel Day-Lewis playing Barack Obama in Steven Spielberg’s movie “Obama,” and not have absorbed the lessons of “Lincoln”?
What seems to escape Dowd is that Daniel Day-Lewis is an actor. He's a multiple Oscar winner, to be sure, but pretending to be Abraham Lincoln is not quite the same thing as being Abraham Lincoln.  Hell; it's not even really studying Lincoln in any more than a shallow, superficial way.

That Dowd thinks that acting in a three-minute spoof of an actor pretending to be the president should promote any sort of insight into President Obama reveals a shocking shallowness in a person who gets column space in the leading newspaper in the USA a couple of times a week.

I would say Dowd should be ashamed, but that would require a level of self-awareness that her writing reveals is itself absent.