It's not just that the tails stop being correlated, it's that there can be a spurious negative correlation. In any of your scatterplots, you could slice off the top right corner (with a diagonal line running downwards to the right), and what was left above the line would look like a negative correlation. This is sometimes known as Berkson's paradox.
This very much reminds me of Michael Polanyi's notion of the ubiquity of "tacit knowledge." See his book "Personal Knowledge."
Great post, Eliezer.
On a separate note, a lot of readers here would probably like Venkat's blog linked above.
For some reason, I'm reminded of the passage from the opening of Augustine's Confessions -- in the true spirit of autobiography, he describes how he learned words and ideas as an infant by being shown extensional definitions:
13. Did I not, then, as I grew out of infancy, come next to boyhood, or
rather did it not come to me and succeed my infancy? My infancy did not
go away (for where would it go?). It was simply no longer present; and
I was no longer an infant who could not speak, but now a chattering
boy. I remember this, and I have since observed how I learned to speak.
My elders did not teach me words by rote, as they taught me my letters
afterward. But I myself, when I was unable to communicate all I wished
to say to whomever I wished by means of whimperings and grunts and
various gestures of my limbs (which I used to reinforce my demands), I
myself repeated the sounds already stored in my memory by the mind
which thou, O my God, hadst given me. When they called some thing by
name and pointed it out while they spoke, I saw it and realized that
the thing they wished to indicate was called by the name they then
uttered. And what they meant was made plain by the gestures of their
bodies, by a kind of natural language, common to all nations, which
expresses itself through changes of countenance, glances of the eye,
gestures and intonations which indicate a disposition and
attitude--either to seek or to possess, to reject or to avoid. So it
was that by frequently hearing words, in different phrases, I gradually
identified the objects which the words stood for and, having formed my
mouth to repeat these signs, I was thereby able to express my will.
Thus I exchanged with those about me the verbal signs by which we
express our wishes and advanced deeper into the stormy fellowship of
human life, depending all the while upon the authority of my parents
and the behest of my elders.
Andy McKenzie -- that was my first thought too. Folks can view the scene here.
FYI, if you look at Asch's 1955 Scientific American article, the lines on the cards were a little closer in length than in the example shown above.
I'm still not sure what you're getting at -- want to email me at email@example.com? Thanks.
Video -- I have no idea what you're talking about??
Not to get too sidetracked, because your overall point about education is well-taken, but this:
A recent study here in the Bay Area showed that 80% of teachers in K-5 reported spending less than one hour per week on science, and 16% said they spend no time on science. Why? I'm given to understand the proximate cause is the No Child Left Behind Act and similar legislation. Virtually all classroom time is now spent on preparing for tests mandated at the state or federal level. I seem to recall (though I can't find the source) that just taking mandatory tests was 40% of classroom time in one school.
is implausible on its face (particularly the assertion about 40% of classroom time -- that would mean kids spent 2+ hours every day taking tests). And if schools are ditching science (really? they're really spending 3 hours a day just on reading skills and 3 hours a day just on math?), that would be a very foolish decision on their part, even if their goal is to show high reading scores. Once kids know how to decode words, the best path to reading comprehension is lots and lots of substantive background knowledge -- such as science, history, etc.
By the way, the paragraphs about opening and shutting the car door are one of the best things I've ever read about the distortion of incentives in organizations.
The post reminds me of one of my favorite scenes from a Hitchcock movie (which I transcribed a while back, knowing it would be useful at some point in the future).
In Hitchcock’s 1938 movie The Lady Vanishes, the heroine Iris Henderson is traveling on a train in the same compartment as an old lady. When the old lady disappears (it later turns out to be connected with a spy ring), Iris scours the train in search of her. She meets a German doctor named Dr. Hartz, who accompanies her on her search for the old lady. But when everyone denies having seen the old lady, Dr. Hartz theorizes that some psychological hallucination must have caused Iris to imagine the old lady’s existence.
But then, finally, Iris finds one woman who admits to having seen the old lady. Iris then confronts Dr. Hartz with this new witness:
“You’ll have to think of a fresh theory now, Doctor.”
"It is not necessary,” Dr. Hartz responds. “My theory was a perfectly good one. The facts were misleading."