Schools test often to teach inequality and hierarchy


At school, our kids are rated and ranked far more often than most adults will tolerate, even though this actually slows their learning! It seems that modern schools function in part to help humans overcome their (genetically and culturally) inherited aversions to hierarchy and dominance. Modern workplaces require workers who are far more accepting than are foragers of being told what to do when, and of being explicitly ranked, and our schools prepare kids to accept this more primate-like environment.

The evidence strongly suggests that students learn better when they are not graded and certainly not when they are graded on a curve.

Subjects worked on different tasks and received performance-contingent payments that varied in amount from small to very large relative to their typical levels of pay. With some important exceptions, very high reward levels had a detrimental effect on performance.

This is Robin Hanson of Overcoming Bias making a plausible point, though I would not view this at all as a recent phenomenon. If anything, accepting hierarchy and dominance is probably less important today than it used to be at any point since pre-history.

Do click through, there's more interesting stuff there.

Gelman galore


Clearing Out My Closet season continues, this time with a number of interesting posts from Andrew Gelman:

Uh.. Um..
I [Mark Liberman] took a quick look at demographic variation in the frequency of the filled pauses conventionally written as “uh” and “um”.



Marginal vs marginal
To me, the most interesting bit of terminological confusion is that the word “marginal” has opposite meanings in statistics and economics. In statistics, the margin (as in “marginal distribution”) is the average or, in mathematical terms, the integral. In economics, the margin (as in “marginal cost”) is the change or, in mathematical terms, the derivative.

If you are jumpy, you are less likely to be liberal
In a group of 46 adult participants with strong political beliefs, individuals with measurably lower physical sensitivities to sudden noises and threatening visual images were more likely to support foreign aid, liberal immigration policies, pacifism, and gun control, whereas individuals displaying measurably higher physiological reactions to those same stimuli were more likely to favor defense spending, capital punishment, patriotism, and the Iraq War.

Friday the 13th, unlucky?
A study published on Thursday by the Dutch Centre for Insurance Statistics (CVS) showed that fewer accidents and reports of fire and theft occur when the 13th of the month falls on a Friday than on other Fridays. . . . In the last two years, Dutch insurers received reports of an average 7,800 traffic accidents each Friday, the CVS study said. But the average figure when the 13th fell on a Friday was just 7,500.

Datacharmer recently made a good comment on this:


Apart from avoiding risky behaviour on Friday the 13th because it is deemed unlucky (which might well be happening), you should also consider that Friday the 13th – unlike other Fridays – CAN’T be Christmas or New Year’s (where people get drunk and drive), and it will also be associated with a lower (or higher) probability of falling before a bank holiday weekend (or I guess in the States Independence day, etc).

I guess all I’m saying that it could well be other factors driving this result other than a change in people’s behaviour because Friday the 13th is ‘unlucky’.

How about accidents on Friday the 12th of Friday the 14th? The article only compares Friday the 13th with an average Friday – in fact, it doesn’t even reveal whether the 13th is least accident prone Friday in the book…



by datacharmer | Sunday, January 22, 2012
  | 0 comments | | Gelman galore @bluematterblogtwitter

If you can prioritise well you are probably not very creative


In a 2003 study at Harvard, Dr. Carson and other researchers tested students’ ability to tune out irrelevant information when exposed to a barrage of stimuli. The more creative the students were thought to be, determined by a questionnaire on past achievements, the more trouble they had ignoring the unwanted data. A reduced ability to filter and set priorities, the scientists concluded, could contribute to original thinking.

The NY Times has more.

I'm clearing out my inbox of its 400+ emails, and many of these relate to stuff I wanted to post here - so expect a regular stream of content. Even if a couple years old, good links always stay fresh!

ASCII 3D


OK, this is geeky - but love it.

Source.





by datacharmer | Tuesday, January 17, 2012
  | 0 comments | | ASCII 3D @bluematterblogtwitter