omenti

the danger of over simplification

In the early 1990s Anders Ericsson of Florida State University went to a music school in Berlin to test an idea about deliberate practice.  The music school had high standards.  Ericsson suspected practice separated the best of the best from the average.  He asked the eighteen year old violin students to think back on how much practicing they did since they took up the instrument.  Then he had the music professors to divide them into three groups - great, good and average.  Those in the great group averaged about 10,000 hours of practice.  The good, about 8,000 and the average practiced around 5,000 hours.  It seemed like a neat result - practice more and you do better.  He published a paper that wasn't exactly rigorous - it lacked statistical measures like ranges and standard deviations and was more of a discussion than a formal paper.  

 

Prof. Ericsson didn't push the result was a bit to the side of his core work and he didn't heavily promote the result.  But others saw a compelling story around that lovely round hour and a work ethic.   One was Malcolm Gladwell.  Gladwell is a great storyteller, but he often oversimplifies and gets things wrong.  The 10,000 hour result has been disproven by more careful studies over and over, but his books and TED talks are enormously popular and have made the idea something of a cultural meme.  

 

Recently I was thinking about something else he said that was misleading. Great storytelling, but misleading.  The more I thought about it, the more damaging it seemed.  It's partly linked to the 10,000 hour story and some unhealthy forms of training. 

 

In Outliers Gladwell talks about a relative age effect.  He uses sports, but it can apply to academics and other areas.  Say the calendar allowing kids to participate in a sport begins on January 1.  Kids born in the first quarter would be  January → March birthdays.  He noticed that ice hockey players born in the first quarter are over-represented and forth quarter kids are  under-represented.  The pattern appeared in several other sports so he set about writing a compelling sounding story.

 

What happens is when  kids are allowed to try out for a sport - say nine or ten years old - many of the first quarter kids are significantly more developed than forth quarter kids.  Most coaches can't tell the difference between maturity and ability and tend to select the kids who perform the task better.  The rate of change at that age is so great that the majority selected will be the older kids. 

 

A problem is the better players get moved to the better coaches and facilities. The talented ones in the chosen pack progress riding a premium training infrastructure.  There may be very talented kids who are later born who miss the advantages of this training and infrastructure who are lost to the system as they miss a chance to develop and are soon left far behind.

 

Combine this with the 10,000 target (as an exercise figure out how many hours a day you need between the age of nine and seventeen to become expert) and you realize specialization needs come early for the better athletes. I'll admit to oversimplification here - this is a fascinating area that has become something of an arms race as, at least in the US, the goal of a college scholarships can force specialization before a kid becomes a teenager.

 

The funny thing is when you look at more carefully you see sixty to seventy percent of the college age players in many sports are first quarter births, but for professional athletes in the same sports the relative age effect almost goes away.  Almost as at the very elite level there's a slight over abundance of third and forth quarter athletes. What appears to be going on is there's a great weeding of talent from college to pro. In many sports late bloomers - kids who got their growth spurt late for example - finally reached parity, but the fact that they had to work harder and learn the sport better ultimately made them better athletes.

 

There are other complexities I won't go into other than mentioning playing a variety of sports rather than concentrating tends to make better elite athletes.  We have a bias when we hear about prodigies like Tiger Woods and tend to assume they're the norm, but it's not. We also tend to forget about the prodigies that never make it.  One estimate is that only about one percent of sports prodigies identified by the media (written up in a magazine) by the time they're teenagers ever make it into the pros.  

 

So the American and some other systems do manage to train a number of elite athletes in many sports and show it internationally in the Olympics.  What about the potentially elite athletes that were never trained?   It turns out some systems cast a much wider net.  The Nordics, notably Norway, push universal recreation and sport for kids as a healthy way to provide fun and lower healthcare costs. Early specialization is discouraged and good facilities are made available to all.   It appears to work very well.

 

I'm far from athletic and am not recommending changing any system (although I think Norway's goal of a healthy population is excellent).  This is an illustration.  Similar issues of pipelining kids exist in music, art and academics.  Broadly speaking STEM education is an example of exclusion and producing a population that isn't as literate as it could be.

 

Back to the storytellers and  oversimplification.  If something isn't important and you just want to get a tough idea across, it might be appropriate, but anything of importance needs an appropriate level of depth. That places serious demands on the author, teacher - anyone trying to communicate.   It's something I struggle with a lot. 

 

 

 

staying upright

minipost

 

Over the weekend many of you probably saw highlights of Simone Biles' extreme athleticism. Gymnastics has a lot of interesting science going on, but balance is a central element.  It's important in many sports.  Athletes need to deal with dynamic situations that place their bodies in positions the rest of us wouldn't be able to recover from.   Here's a little exercise to check your balance and muscle control.   No equations or math.

 

Stand still with one foot in front of the other - the heel of your left foot touching the toe of your right.  With your hands relaxed at your sides shift your weight to one of your feet.   See how well you're doing at thirty seconds and then at a minute. How are your calf muscles doing?  It can be surprisingly difficult.  Spreading your arms out sideways should make it easier.   Arms in again and lean to your left or your right.  Not exactly stable is it?  Try again with your arms out..  An improvement, but probably not by a lot.

 

Try a normal standing position like you are talking to someone .. feet side by side.  Even with your arms at your side, you're much more stable. 

 

Now go back to one foot in front of the other again and crouch down as low as you can.  You'll probably find balancing gets easier the lower you go.

 

I won't do the physics, but when a vertical line through your center of gravity falls outside the base of support created by your feet you're out of equilibrium and your body has to figure out how to compensate or suffer the consequences. As you move your feet further apart you broaden your base of support and become more stable Divers often start their dives by leaning forward and moving their center of gravity away from their standing base of support.

 

You can also increase your inertia by spreading your limbs out.  This slows your wobbling giving your body a better chance of dealing with the situation.  The killer way of doing this is to carry a tightrope walker's pole.  This dramatically increasing their moment of inertia (in one axis) slowing what would be dangerous wobbles to the point where their reflexes can deal with them.

 

A few days ago I saw this.  I'm not a fan of scooters as the physics is wrong for stability,.  At the same time I'd hazard Simone has the balance to handle one.  Not to mention her four foot eight inch frame gives a low center of gravity.   I asked a physical therapist who has to deal with balance about scooters.  The advice: you shouldn't be on one unless you can close your eyes and balance on one foot for thirty seconds.  The ability to do this drops dramatically with age.   I won't say much more about scooters as I'm negative and will get flames, but if you must ride one make sure you wear a helmet and don't go fast.  

 

 

order! - a minipost

Apparently a math puzzler became something of a theme on the Internet..  a half dozen people asked me what I thought the answer was

8÷2(2+2)=?

Some came up with 1, others with 16.  Apparently there were near-religious arguments. A mathematician would tell you both are incorrect - the question posed is ambiguous and not an answerable bit of math ..  at least not generally.

 

The problem is the order in which one evaluates expressions.  It turns out the one you learned in grade school is a bit different from the one you may have had when you learned algebra. If you remembered grade school you probably get 16.. algebra people are more likely to get 1.¹  If your algebra teacher was more careful they would have said the expression is wrong - you need to add parenthesis to make it unambiguous. The exception would be if the only people you communicate with agree on representation. That can be a big if..

 

Taking it a bit further, the simple rules you learn in secondary education don't cover don't cover unary ±, which implicitly have lower precedence than exponents on one side and higher on the other!  For example

-x³ → -(x³)
x^-3 → x(^-3)

This is so well agreed upon that no one uses parenthesis in this case.  Historically juxtaposition was treated as implicit multiplication, but that led to ugliness like

1/3x →  1/3*x →  (1/3)*x
a^2x →  a^2*x →  (a²)*x

uck! 

People decided juxtaposition of numeric literals is like a unary operator ..  so the 2 in 2x is attached to the x like the - in  -x.  

 

Back to the original problem. The fact that people had different interpretations and mentioned rules from school meant a better rule was required.  The problem needs to be unambiguous to anyone who might encounter it.  This is an issue for computer languages - different languages can parse the same written expression differently and come to different results.  Agreement on standards is an issue too ..  the Mars Climate Orbiter was lost as  teams at JPL and Lockheed Martin had different takes on a single critical bit of data - one used metric units, the other english..   when the retrorockets on the spacecraft were fired to go into Martian orbit the spacecraft burned up in the Martian atmosphere - it was literally lost in translation.  And this was code that passed multiple very careful reviews - code written for space probes is some of the carefully crafted software period.  Just wait for complex coordination systems and things that move with people nearby or inside.

 

That said there are some areas were common agreement among practitioners creates a local set of standards..  Einstein summation notation in physics is confusing to outsiders, but all physicists know it. And then there's my favorite - the double factorial.  In math (n!)! is not n!! ...  (note that I also have the problem of people interpreting ! as an exclamation point:-)

 

This local agreement is probably true in most fields - even descriptions of an action in a sport are local to the sport.  We all use local shorthand - it's a form of jargon, but we need to know when we can use it and when we need to be more general even it it's awkward.

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¹ In one case 8÷2(2+2) → (8÷2)*(2+2) = 4*4 =16

   in the other 8÷2(2+2) → 8÷(2*(2+2)) = 8÷(8) = 1

 

 

is the drug test fair and the prosecutor's fallacy

a minipost

Some sports have doping issues and there is drug testing in many of these.  There's always an issue of how good the tests are, but there's also an issue of how fair they are and how good they have to be to be fair.   The best way to illustrate this is with an example.

 

Consider a sport with 1000 players - roughly the size of major league baseball in the US .  Suppose steroid abuse is an issue and there's a test with 95% accuracy.  And assume somehow it's known (or strongly suspected) that about 5% of the players are abusers.  These are artificial numbers, but it's just an illustration.

 

What if the players are tested?  We expect 50 to be abusers and 950 to be clean.  The test is 95% accurate.. so 48 (rounding up from 47.5) are correctly identified.  So far so good.  Now consider the 950 clean players..  5% or 48 (rounding up again) are incorrectly labeled as abusers.  So of 1000 players there would be 96 positives and only a fifty-fifty chance of being right. Careers can be be ruined ..  the stakes are high.

 

A way to sort out these conditional probabilities was described the The Reverend Thomas Bayes in the mid 1700s in a paper called Essay Towards Solving a Problem in the Doctrine of Chances.  The good Reverend described the relationship between the probability an athlete is an abuser given a failed test and the probability an abuser fails the test.   Consider these probabilities (apologies for notation)

P(A) = probability a drug test is positive

P(B) = probability a player is an abuser

P(A|B) =  probability an abusing player tests positive

P(B|A) = probability a player has taken drugs if their test is positive

Perhaps the most important takeaway is that P(A|B) and P(B|A) are not the same!  It's a very common prosecutor trick to fool the jury into thinking they are - so common that it's called the prosecutor's fallacy.  But to the problem at hand.

 

We want to know P(B|A).  We already know P(B) or at least we have the 5% estimate.  So P(B) = 0.05.  This also gives us  P(not B)  = (1 - 0.05) = 0.95 as P(B) and P(not B) must add to 1.0. We also have 47.5 (I'll go with the fractional athlete here) of 1000 drug free athletes tested positive, so P(A|not B) = 0.0475.

 

Bayes derived a formula showing how all of these relate.  Sticking with our notation:

 P(B|A) = {P(A|B) *  P(B)} / {P(A/B) * P(B) + P(A|not B) * P(not B)}

                         = {0.95 * 0.05} / {0.95 * 0.05 + 0.0475 * 0.95}

                         = 0.513

This is a very unacceptable test!  Although 95% accuracy sounds good on the surface, it only finds a bit better than half the abusers and incorrectly labels a lot of players.  For fun try a 99% probability and a perfect 100%  to see what's happening. 

 

You can have much more complex conditionals, but this is the general idea.  You really have to think things through a bit..

 

 

local transportation - changing a complex system.

a minipost

There has been quite a bit of activity with escooters in cities as well as ebikes in the past year or two.  I'm hugely in favor of walking, bikes and ebikes - negative on scooters - but it needs to be recognized these are elements of highly localized transportation systems that have a lot of infrastructure, legal and social norms and other elements that tend to have a lot of inertia.¹

 

Change can happen, but meaningful change will take time.  Some areas are easier than others, but the recognized leaders in Denmark and the Netherlands required about twenty years before serious change took hold and fifty years in they're still still learning and experimenting,  The bad news is much of the geography that was determined by the car is wrong if you want change. The good news is there are a number of examples that addressed very different initial conditions and evolved to good enough solutions.  It is non-trivial and the bike or ebike is not the major component.  A lot of hard fought learning exists.  There are some folks who have written extensively on these issues:  David Levinson (his books, blogs and mailing list) and Horace Dediu (lots of work on micromobility!), and Jeff Speck (books) on walkable cities.  If you're interested in the physics and system level issues I'm always happy to chat.²

 

Normally I'd go on for pages at this point, but this is a mini-post, so check out these short videos

 

The Dutch are the world leaders (the Danes are close, but..)  - that said there's a lot of experimentation and variety in the country.  Utrecht is an excellent example near the top:

Just as important, tropical Oslo has decided to make a major change. . an example of a city in the process of doing something (there are many others and there will be an explosion of activity in the EU in the next two or three years .. unfortunately I'd only count one in North America)

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¹ Many systems have hidden externalities and complexities.  I've heard more than a few security experts say voting is one of the most difficult and complex systems they can think of.  It's much larger than just voting machines.  And these complex systems have often hidden externalities.  The popularity of the automobile created the suburbs and other non-optimal bits of infrastructure that have had an enormous impact on global warming..

² I've worked with a couple of governments looking at the future of transit.  I tend to start with the physics and then explore the systems.

 

 

moonshine

"Land sakes"

 

A hot Sunday afternoon almost exactly fifty years ago.  My sister and I were on the couch next to my Grandma King.  Walter Cronkite was out connection to the small spacecraft as it slipped towards touchdown on the Sea of Tranquility.  I was just a kid, but I knew this might be one of the most dramatic moments I'd witness.  About then she said those two words and I had another realization.

 

Spacings between the generations on my mother's side were large.  I never met my Grandfather - he died working as a telephone lineman for the Bell Telephone System in Utah, Idaho and Montana years before I was born.  He was born a few weeks before Custer's Last Stand.  Grandma was born in 1889 in the Territorial Utah theocracy.  She would tell stories of the first motor car she saw, of a Butch Cassidy-like thug who ran a small business protection racket, when she read about the Wright Brothers a few years after they flew, and why moving pictures were awful (the batteries emitted a stink).  They didn't have indoor plumbing until 1940, but the big event was getting electricity around 1930 .. bigger than indoor plumbing, bigger than their Ford.  We couldn't get her on an airplane.  Airfares from Great Falls to Salt Lake City were cheaper than riding the dog, but she heard about crashes for much of her adult life .. in fact real air safety didn't begin until the mid fifties, so she wasn't that far off. 

 

And here she was watching glowing phosphors on a piece of glass, listening to a human voices coming from thousands of miles away along with two that had traveled by radio requiring about one and a quarter seconds to find antennas on Earth..

 

What happened in the next few minute was breathtaking, but I found myself wondering if her life spanned greater fundamental change than any other time in history.  Would she see more fundamental change than I would?   You start thinking about what fundamental means,.  It still keeps me up at night.

 

Now there is talk about going back - sending people to the Moon and to Mars.  I'm afraid I don't see it as a big deal and consider it wasteful.

 

Others have articulated what Apollo did for America and the world.  So much was spent - nearly 4.5% of the federal budget was NASA in the mid 60s - that technologies advanced at a much more rapid pace than we'd normally see.   The computer and semiconductor industries were jumpstarted.   Secondary school science education changed and a large STEM pipeline to Universities was created.¹ There was a morale boost for a few years, but it faded against an awful war and dramatic social change on several fronts.  A moon landing, iconic as it was, faded to insignificance in a few years.  The last three Apollo missions were cancelled largely because the public lost interest and politicians responded. 

 

I'm a big proponent of space exploration and the unmanned space program has been brilliant.  Putting people into space is not only expensive, but probably wrong biologically.  We didn't evolve to live in such harsh environments.  Most of the people who have flown in space have orbited in a region where the Earth's magnetic field shields them (and us!) from radiation.   Without Earth's magnetic field it is unlikely life could have evoled on the surface or in shallow water.  Anyone who stays on the Moon or Mars will have to live underground or in elaborate radiation shields.  There are issues of water, air, food, human psychology, low gravity muscle and bone degradation and so on.   We're the wrong tool for the job.

 

People, life support systems and rockets didn't scale by Moore's Law, but computation has.  What a non-human kilogram in space or on another body in the Solar System can do has made leaps opening and now we have commercial businesses exploiting near Earth orbit and students orbiting satellites.  We can build increasingly intelligent probes that are space faring.  Plucky (I've wanted to use that word) robot explorers  are getting better and better and do almost all of the meaningful exploration of the Solar System.  We're really good at building and flying them as well as analyzing and wondering about what they tell us.  

 

There are those who sayt we have to leave Earth - that it's our destiny and we've ruined the Earth.  That strikes me as defeatist and driven by more by science fiction than logic and science.  A failure of the imagination.   Another explanation is adventure.  Adventure is fine, but you can't call it real exploration at this point.   My vote is for learning about the Solar System and beyond in a cost effective way as we work on repairing the damage we've done here.  

 

We can always look up and admire the Woman in the Moon.

 

 

I would be remiss if I didn't point out that Grandma King swore in Irish Gaelic.  Sadly I never learned.

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¹ I've written quite a bit about the good and bad of the approach.  Arguably it's created an over-supply of scientists at the cost of ignoring and even alienating the majority of students. It's sad it hasn't changed much since.

complete with lighter and ashtray

About a month after Apollo 8 circled the moon my Dad and I traveled the two miles to Malmstrom Air Force Base for a tour of the SAGE installation.  A number of these Semiautomatic Ground Environments were scattered around the country to detect and coordinate a response to bomber attacks from the Soviet Union.  The cost was enormous - more than the Manhattan Project - with the effort resulting in several computing "firsts".    It formed how I thought of computing at the time, blinding me to another more important revolution that was underway.

 

The SAGE building was enormous. It had to be to house the roughly supermarket sized FSQ-7 computer.  These were tube based and designed to be redundant enough that statistically likely tube failures could be repaired by airmen with replacement modules that could be swapped inside of a minute.  Outside the blast hardened building was a large cooling plant to keep everything from melting down. 

 

The big show came with an airman pointing a light gun at a large circular display with radar blips from a number of radar stations. He'd pull the trigger and get some basic information on the airplane - friend or foe id, call sign, altitude, speed and heading.   Should an intruder be spotted, interceptors would be scrambled.  In Great Falls that meant F-106s from the Montana Air National Guard about seven miles to the West on Gore Hill.  It was co-located with the commercial airport.  I believe it was the only commercial airport in the US with nuclear weapons on site.  All this was really impressive, but so was the fact that each of the radar terminals had an ash tray and a cigarette lighter.

 

I thought computers were huge expensive beasts - rare things that I might get to program some day, but certainly not anything that would be part of my life.   It turned out what took place the month before provided a hint that didn't register until much later.

 

While many of the fundamental ideas behind computing had been put together in the fifties and sixties, miniaturization and the real start of Moore's Law really came with the space program.  Simple integrated circuits had been developed, but size and weight requirements on the Apollo command module and the lunar lander called for huge advances.  The advances were borderline unthinkable, but solved with cubic money and outstanding minds.  My favorite example is the Apollo Guidance Computer.  Books have been written and I wouldn't add anything, but here are a couple of gee-whiz links.

 

The first is from Ken Shirriff's terrific retro computing hardware blog. Ken's hobby is reverse engineering ancient electronics and restoring old computers.  In this post he talks about core rope and the guidance computer.  Programs were literally woven into a rope that was a simple core memory system.  It's elegant in a hammer and tongs sort of way.  If you don't know how core memory works go and check out the photographs and skip the technical parts of the text.  It's a remarkable story involving women who could sew and sexism.  And if you have the background it's even more interesting.

 

And here's a nifty Apollo Guidance Computer Simulator.   Print out the instructions or open them in another window and play astronaut!  Just in time for the 50^th anniversary in a few weeks.

 

The dramatic infusion of R&D money built the semiconductor IC industry and established starter markets. There many other stories - like how AT&T and IBM worked together behind the scenes in the 60s and early 70s to bootstrap the necessary tool building. They did it for their own benefit, but without it we might be a decade behind where we are now.  Perhaps a more interesting question might be:  'would that have been a good thing?'  I've been thinking about that a lot recently.

 

the question of getting bent and slowing down

 

(a) Without resorting to equations, why light slows down when it travels from air to sheet of glass and why it speeds up when it exists?

(b) Again without equations, why does light refract?

 

For the past decade and a half a friend in the engineering department of a very large and famous university in the midwest is infamous for asking "unfair" questions of graduating seniors.   The student's grades aren't affected. He's interested in how deeply students thought about everyday phenomena that are fundamentally important to engineering,  He hopes to learn about teaching in and outside of the department as well as the curiosity of the students. 

 

This year's question was a disaster.  Nearly two hundred students took the exam and four got part a correct.  The same four gave the only correct answer for part b.  Refraction is really important - lenses wouldn't be possible, there wouldn't be rainbows.. there wouldn't even be vision.  It has practical use throughout engineering, even finding use in certain types of market trades where gaining an information advantage is important.   I'll answer part a and leave b for another time because it requires a bit more background.

 

In high school you probably learned the index of refraction of a transparent material determines the angle light will bend if it travels from one transparent material to another.  The greater the index, the greater the bending.  Some (approximate) values are:

 

        a vacuum      1.0000

        air                    1.0003

        water               1.33

        glass                1.5  (it can vary from about 1.5 to nearly 1.75)

        polystyrene    1.55

        sapphire          1.77

        diamond          2.417

 

You probably also learned that light slows to the speed of light divided by the index of refraction in a transparent material, If light travels at c - the speed of light - in a vacuum, it slows to c/1.33 or three quarters the speed of light in water and c/1.50 or .two thirds the speed of light in glass.   The illustration shows light moving from air (for most purposes you round the index of refraction of air to 1.000) to a sheet of glass and out the other side. 

 

The answers given by most of the students clumped into two categories - both wrong.  It's interesting to consider them before moving on to what really takes place.

 

One idea was to suggest light bounced from atom to atom (or molecule to molecule) in the glass taking a three dimensional pinball path,  It would effectively travel a longer distance making it appear to take longer to go from one side to the other.  The problem is light would effectively scatter out even in perfectly clear glass.  A narrow beam, say from a laser, would light up a broadening region inside the glass and the would continue as a broad cone once it left. Some of the light would  even bounce backwards creating an undirected glow on the first side. The clearest materials would be blurry and dim to look through with the  blur increasing with thickness of the glass. Crisp images would be impossible. 

 

The second popular answer was to suggest atoms (or molecules) absorbed the light and then re-emitted it.  It takes a bit of time for them to do this, so the effect would be to slow the light down. The problem is when an atom absorbs and then emits light it doesn't remember the direction the light came from and can emit it in any direction.  Now you have the glowing problem again.  There are other issues - among them atoms and molecules have very special and narrow frequencies they absorb an emit (quantum mechanics).  The effect would only happen for a few very narrow colors and some colors would be completely absorbed. 

 

We don't see either of theses, so something else is going on.

 

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I think the simplest way to look at this is to consider light as a wave.  As it travels along there are oscillating electric and magnetic fields perpendicular to its motion.  The animation shows the fields happily moving along with the electric field in red and the magnetic field in blue.  

 

 

You've probably come across the superposition of waves.   Take two waves with the same wavelength and add them together.  If the peaks of one line up with the peaks of the other, you get a larger wave with peaks and troughs twice as big.  If the peaks line up with the troughs, they cancel each other.  The next gif shows two waves and the result of summing them .. 

 

This turns out to be what we need conceptually. 

 

The electric field in the light juggles the electron clouds of the glass molecules causing them to move up and down.  They don't move in direct unison as the mass the molecules dampens the motion, But they still jiggle and very rapidly.  If you take a charge and shake it, you get an electric field. The jiggling molecules are producing their own electric field as they feel the light's electric field.

 

That's it!  

 

The electric fields produced by the jiggling molecules as they dance to the tune of the light combine with the electric field of the light.  The math is a bit messy as you have to consider all of the molecules, but the combined field moves below the speed of light -  just like you had divided it by the index of refraction.   When Thomas Young discovered the index of refraction more than two centuries ago he was only able to predict how light would bend, no one knew what was really going on.  The key came later in the 19^th century with an understanding of Maxwell's equations.

    

An acceptable answer could have been something like:  the electric field of light inside the material jiggles the electrons of the material's molecules generating another electric field.  These fields combine to produce an effective field that travels slower than the speed of light in the vacuum. 

 

Of course you could ask embarrassing questions in any department and discipline and that makes you wonder about education. 

 

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I should add that there are deeper ways of thinking about this.  Quantum electrodynamics gets at the interaction between photons and electrons, but it gets very messy and for most applications would be overkill.   It's  like Newtonian physics and Relativity ...  for almost everything we do Newtonian physics is good enough.

 

 

an ecology posed by a children's song and multidisciplinary problems

Last week I read Range: Why Generalists Triumph in a Specialized World by David Epstein.  David writes well  I've recommended The Sports Gene as another excellent read.   In Range he talks about real world messy problems that often poorly defined and open-ended.  The really interesting ones usually require a range of backgrounds.  Experts often do worse than generalists.  If you have a group of people, you want a range of expertise and backgrounds.   

 

You've probably heard of Fermi calculations.  Enrico Fermi liked to frame problems in such a way that you might be able to approximate an answer using common sense and a few bits of information.  Things like "how much water flows through the Mississippi River in a year?"  or "how many piano tuners work in New York City?"  They're extremely common in physics and are used to think about how good or bad a conjecture is.  The type of question you can get a handle on in your head or on the blackboard.

 

There are many other approaches to problems. The school where I did my undergrad work has a course that teaches multidisciplinary thinking.  Although it's a physics class, it really isn't about physics - or at least it doesn't have to be.  People get together a couple of times a week for a few hours and a problem is posed to talk about.  Students come from a variety of backgrounds.  What is common is serious motivation and curiosity.  There aren't midterms or finals, but there is a project each student proposes and works on.  They're given some funding and access to other class members, professors and grad students.  And each week they're immersed in the two hour sessions each featuring something that is best approached as a cross-disciplinary problem.  They learn to sort out the various strengths and weaknesses of the other students and the professor.

 

Getting into the course is difficult. About a hundred apply and maybe six are accepted  You have to pass a couple hurdles - problems you spend about four weeks each on showing you can bring a range of thought to the table.  You must show they're capable of cross-disciplinary thinking.¹  A hurdle problem I'm familiar with was  posed as a line from a children's song:²

Mares eat oats, and does eat oaks, and little lambs eat ivy.

The question is:

Considered in an ecological sense, we have three species each of plant and animal life that interact in a finite geographical area. Supposing that we start out this system with roughly equal numbers of the six species, determine the way the system changes with time.

You have four weeks to come up with something clever and compelling.  Then on to the next hurdle.  The class has had extraordinary success over the years and is something of a legend.,

 

Very few people have a great range of background and expertise.  At least in the US we seem to value those who are broad less than those with a very narrow deep expertise.  One of my favorite thinkers was a mathematician some of you knew - Norm. He would sit and listen to ideas coming from a variety of backgrounds.  Later .. a few minutes to a week or two .. he'd stop you and say "Let me see if I understand what you were saying"  Then he'd proceed to give a much deeper and better thought-out version of what everyone had been trying to say, adding his own bit in the process.  Not always, but often enough history or art might be part of the framing.   These sessions were marked by deep play as well as chocolate coated coffee beans.  Play is the glue that allows communication across disciplines .. even if it's in your own head.

 

My own range isn't that great, but Norm and others - friends who have very different backgrounds - have changed the way I think.   I have this habit of "tithing" my time to the projects of friends.  I'm particularly interesting in areas outside of physics and math as I end up learning something and find myself in Norm's shoes at times.   This broader approach of posing and approaching questions strikes me as richer than the traditional expert deep dive as you can always add expertise where you have it when it's useful.

 

I've had a bit of serious insight on a very difficult problem that changed how I saw the world.  Insights came from a forestry program, a couple of sociologists and a professional volleyball player who has a degree in microbiology.  There are dozens of other problems where outside insight has combined with my own contribution to be a bit out of the box. And who would have thought thinking about bats would be just the right analogy for what turned out to be a neurology problem I didn't realize I needed to know about...

 

I don't know if I manage to help others.  If I do it's probably by offering a bit of thinking that might seem novel as their background is different.  At the same time I'm often lost as an outsider in their world until I start working in it for awhile.  I probably don't get very good at it, but it's the diversity that might be useful.

 

I'm very much against the hyper-specialization in STEM focused education we seem to be moving towards.  There's enough change in the world that the humanities, liberal arts and just practical skills are increasingly necessary. There has been some work on teaching cross disciplinary thinking. That strikes me as having great potential. 

__________

¹ As these are freshmen when they work on the hurdles it's interesting to look at their backgrounds. It's a bit of a problem as so few have taken the course, but it's been around for decades.   I won't go into that here, but it's very different from those of kids who focus on standardized tests and assigned activities.  A really interesting question is how much of the ability to acquire cross disciplinary thinking is wired in and how much is learned. I have suspicions, but that's beyond this post.

² Not to be confused with the song "Mairzy Doats and Dozy Doats" from the late 40s:-)  It's sort of a homonymic phrase. 

 

 

making and sparking

"No - we took all of that out years ago.  It's just not relevant anymore."

 

Fifteen or so years ago I visited the local high school to see if they had an adult education program that would let me use the student shop.  We don't have enough space or cash for a proper shop at home and frankly I'm not that good at wood or metal working, but every now and again the urge strikes.  

 

I'm not arguing that shop class was well thought-out or even useful - it wasn't when I was a teenager - but there's something to being able to design and build something.  On my own I did build a few things:  a couple of telescopes, some amateur radio gear, model airplanes and a seismometer.  Although the attempts of a kid, they were enormously powerful learning exercises.  I learned how to solder, how electronics works at the component level work and a bit of practical optics.  I even got to the point where I designed a transmitter and a simple analog computer.  Commercial equivalents were better - they were designed by people who actually knew what they were doing - but I was learning the basics for design and that is much more powerful.  

 

In grad school the ability to design and build was essential - so important even the theory students had to learn a few basics..  I knew enough about electronic design, but had never done any metal work.  Metal shop was wonderful. The shop was well equipped and managed with expert help around most of the time. We were given a couple of simple projects.  Once you made those you had to show you could do it with greater precision.   We were finally given shop keys when  they thought we wouldn't destroy the machines or ourselves. They encouraged us to come in and play. 

 

I remembered a project in an ancient issue of Popular Science that fascinated me when I came across it in the library as a kid - a Stirling engine.  I decided to build one of my own based on a bit of insight into better materials.  The first was very inefficient - about 30 watts at the flywheel using a hot plate for a heat source.  A minor redesign moved it past 100 watts.  The design and construction was a wonderful diversion to the classes I was taking.

 

Times have changed.  While engineers generally know how to build things, Spending a bit of time teaching in Oberlin's Technology in Music and Related Arts I found art majors and music students more adroit at "making"   than computer science students.  Programming is clearly building, but it's useful to tie it to the physical world every now and again.  Some schools stress that more than others.

 

It doesn't happen often, but when someone mentions their kid is interested in learning about computing I recommend simple inexpensive computing modules that interface with the real world.  Arduino and Raspberry Pi for example.  An enormous amount of "how to" videos and documents exist and beginners can start with very cheap kit. They can have quick success getting something working from cookbook like plans.  At first no real skills other than patience and the ability to follow instructions are necessary.  Then, with the application of curiosity,  learning begins,   You change this and that to change what it does.  You can write simple or complex programs and you can buy interface modules, usually called shields, that  interface with the outside world.  

 

People with that spark - the desire or need to do something they can't go out and just buy - make this interesting.. A dance major at Oberlin learned about Raspberry Pis in her computing for arts class.  She sewed an accelerometer to her leotard and connected it to a raspberry Pi on a belt.  Information was liked to her laptop via by bluetooth.  For fun she connected it to lights that changed color with changing acceleration.  A friend on the women's softball team saw it and thought it would be useful in pitching practice.  Another version with software tuned to the needs of softball was built and the coach is thinking. Of course you can do this with an Apple watch, but its much more difficult to make it do just what you want and this way you develop a deeper understanding. 

 

And so these things go..  Which brings me to something exciting.

 

People who build and design get good at it with practice and are on the lookout for new challenges.   A few of you may be familiar with Panic - a tiny company that makes a few very nice applications for developers.  They're profitable by themselves but use some of that profit to fuel their need to explore.  A few years ago, out of nowhere,  they came out with a video game called Firestarter.  It wasn't one of your multi million dollar developments, but many people loved it because it was beautiful, clever and absorbing.  They more than broke even which wsa good enough. There has been anticipation about another game in development called the Untitled Goose Game.  But again out of nowhere came something completely shocking and wonderful.

 

Hardware

 

These guys decided to build a minimal hardware game player called the Playdate. People who have seen it seem to be somewhere between excited and ecstatic. 'Impossible to resist' keeps coming up.  I won't go into details because I'm not a game player and I don't know much other than  care appears to have gone into every step of development.  They even wrote their own operating system. (that actually makes more sense than Linux for a very small game).  They made it for themselves because it was a challenge they couldn't resist.  Maybe it will break even, maybe it won't, but it won't break the company if it flops.  I'll probably get one and I'm not a gamer.  

 

People sometimes ask me why I'm passionate about a few odd things that not many other people find interesting.  Many of us have a spark - a playful spark.  They're all different and that's wonderful.  Some of us aren't very good, others are the opposite, but that's not why we do it. We may or may not get paid, but that probably doesn't matter much.  Sometimes I think it's better to not be paid as there's more freedom (assuming what you do is cheap).  Often you find yourself learning a variety of things you never thought about as part of pursing your spark.  In my case that can mean designing and building.  I'm not very adroit at that part, but it's a useful tool and I slowly improve with experience.  I'm in awe of those who thrill to be beauty of creating design and objects.  

 

About fifteen years ago I found a poem that sums it up .. 

To be alive: not just the carcass
But the spark.
That's crudely put, but…
If we're not supposed to dance,
Why all this music?

                - Gregory Orr