computers, classroom, climbing, etc.

Saturday, August 8, 2009

The gatekeepers of knowledge

Howard Rheingold recently blogged on evaluating the quality of information. A good post - he says about the same as in thousands of similar texts, but does such a good job that I'll probably use this as a standard text in class for a while. This is quality because he both includes the latest cool tools, but makes his discussion fundamentally about attitude, not gizmos.

The basics here are of course critical thinking and source evaluation - good 19th century skills, it's just that kids have to start learning this stuff earlier nowadays and we have new tools to help us. It would be possible to lament the emergence of a world that requires these changes - wasn't it better when our main access to information was books, with their more rigourous editing process? Andrew Keen has built a whole career lamenting the disappearance of the 'gatekeeper'. He is mostly focused on news and culture, but the idea is valid everywhere: "Before", most of our media exposure was vetted by experts, so what you read in books, for example, you could mostly count on. "Now", any idiot with a modem can publish, so we all have to be our own gatekeepers about thousands of topics we are not experts on. (The Telegraph's technology blogs are a hotspot for the debate around 'gatekeepers'.)

What really got me thinking was a comment on Rheingold's post by someone called dogu4: "Questioning one's sources is useless, unless one is questioning oneself as well. Consider many of the supposedly irrefutable facts regarding human health just in the last decade or so". A seed in the back of my head suddenlty became a full-grown douglas fir. I must admit I think about Warren and Marshall a good deal. They are the two Australian scientists who in 1982 found good evidence to link stomach ulcers and h. pylori bacteria. Despite this connection first having been noticed in the 1890s, this finding went against several received truths of medicine and Warren and Marshall had trouble getting their findings accepted. It took well over a decade for the connection between bacteria and stomach ulers to be fully accepted.

Some of the other commenters clearly didn't understand what all the fuss was, but in my worldview, Warren and Marshall are key figures in the history of ideas. Both as a symbol of how knowledge progresses and practically, as a watershed in thinking about infectious diseases. Try a quick thought experiment. Imagine that the Web existed in 1983. Ulcer sufferers searching for information about their condition come across information about h. pylori. The chances are that neither their primary care giver nor their treating gastroentorologist would have heard of the study and that they would have refused to prescribe antibiotics. Within a year or so, so many people would have stumbled across Warren and Marshall's work that the medical establishment would have been prompted to respond more actively to their ideas - mostly likely producing a wave of anti-antibiotic statements from the medical establishment. (In real life, in those pre-Web days, Warren and Marshall were dealt with mostly by ignoring them.)

The point is, it is easy to find examples of how the old 'gatekeeper' model didn't always work. It was just harder to see its weaknesses and harder to get a debate going. The Andrew Keens of the world can lament all they want - the old model has not fallen apart merely because of new technology, but because it didn't always work so well. Now we are groping towards something new. Rheingold's post is a good example of the kinds of ways that are emerging to deal with this new, gatekeeper-less world.

(An example - this spring I did a whirl around American health web sites, checking for their view on feeding raisins to children. I limited my search to 'serious', mainstream sites, mostly those vetted by medical doctors. I did not find a single site that mentioned mycotoxins - they all limited their discussions to considerations for the teeth. It's odd - mycotoxins aren't some kind of secret (just Google the word and see what happens) - do these people know how to publish to the internet, but not how to do basic research? So in this case, I'm left without a 'gatekeeper' to help me sort the data here - I just have to bring all my research skills and critical thinking to bear to make my own decisions.
This is the world we not only have to live in, but prepare our students for. Clinging to the textbook and locking down all computers looks like head-in-the-sand behaviour from here.)

Monday, August 3, 2009

Niels Bohr and the barometer

I was recently reminded of a classic urban legend:

The following concerns a question in a physics degree exam at the
University of Copenhagen:

"Describe how to determine the height of a skyscraper with a barometer."

One student replied:

"You tie a long piece of string to the neck of the barometer, then lower the barometer from the roof of the skyscraper to the ground. The length of the string plus the length of the barometer will equal the height of the building."

This highly original answer so incensed the examiner that the student was failed immediately. The student appealed on the grounds that his answer was indisputably correct, and the university appointed an independent arbiter to decide the case.

The arbiter judged that the answer was indeed correct, but did not display any noticeable knowledge of physics. To resolve the problem it was decided to call the student in and allow him six minutes in which to provide a verbal answer that showed at least a minimal familiarity with the basic principles of physics.

For five minutes the student sat in silence, forehead creased in thought. The arbiter reminded him that time was running out, to which the student replied that he had several extremely relevant answers, but couldn't make up his mind which to use. On being advised to hurry up the student replied as follows:

"Firstly, you could take the barometer up to the roof of the skyscraper, drop it over the edge, and measure the time it takes to reach the ground. The height of the building can then be worked out from the formula H = 0.5g x t squared. But bad luck on the barometer."

"Or if the sun is shining you could measure the height of the barometer, then set it on end and measure the length of its shadow. Then you measure the length of the skyscraper's shadow, and thereafter it is a simple matter of proportional arithmetic to work out the height of the skyscraper."

"But if you wanted to be highly scientific about it, you could tie a short piece of string to the barometer and swing it like a pendulum, first at ground level and then on the roof of the skyscraper. The height is worked
out by the difference in the gravitational restoring force T =2 pi sqr root (l /g)."

"Or if the skyscraper has an outside emergency staircase, it would be easier to walk up it and mark off the height of the skyscraper in barometer lengths, then add them up."

"If you merely wanted to be boring and orthodox about it, of course, you could use the barometer to measure the air pressure on the roof of the skyscraper and on the ground, and convert the difference in millibars into feet to give the height of the building."

"But since we are constantly being exhorted to exercise independence of mind and apply scientific methods, undoubtedly the best way would be to knock on the janitor's door and say to him 'If you would like a nice new barometer, I will give you this one if you tell me the height of this skyscraper'."

The student was Niels Bohr, the only Dane to win the Nobel Prize for physics.

(text collected by snopes.com in '99)

There are lots of 'points' to this story, but what stands out to me is the challenge to educators here. Are our 'open' assessement questions really open, or are they multiple choice without the options being clearly presented to our students? How ready are we to accept pupils thinking way 'outside the box', particularly in formal assessment? How ready are we to accept that some of our pupils may be smarter than we are?

The story is also a good one because of the deliberately provacative attitude of the student. He must have understood from the beginning the answer the examiners wanted, yet some combination of self-importance, humour and lack of respect for formal education makes him risk his exam by giving an alternate answer. Even under the second chance he is given, he is deliberately provocative, clearly making a point of his disdain for the exam. I know many educators who would have trouble standing for this kind of disrespect coupled with 'the wrong answer'. How do we react when the next Niels Bohr appears in our classroom?

The choice of physics for this story is also telling - 'doing physics' requires questioning basic assumptions about the nature of reality, but teaching phyics easily falls into a pattern that unfortunately does not nurture the kind of thinking physicists need.

As an educator hearing this story, I am reminded that humility is one of a teacher's most important qualities.

Oh, and the story? Probably not completely true. May have happened, but no-one can prove it was Bohr. The part about him being the only Dane to win the Nobel prize for physics is also not true, but it was when this story first surfaced in the '50's.