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896 points tux3 | 1 comments | | HN request time: 0.199s | source
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jerf ◴[] No.43546861[source]
One of my Core Memories when it comes to science, science education, and education in general was in my high school physics class, where we had to do an experiment to determine the gravitational acceleration of Earth. This was done via the following mechanism: Roll a ball off of a standard classroom table. Use a 1990s wristwatch's stopwatch mechanism to start the clock when the ball rolls of the table. Stop the stopwatch when the ball hits the floor.

Anyone who has ever had a wristwatch of similar tech should know how hard it is to get anything like precision out of those things. It's a millimeter sized button with a millimeter depth of press and could easily need half a second of jabbing at it to get it to trigger. It's for measuring your mile times in minutes, not fractions of a second fall times.

Naturally, our data was total, utter crap. Any sensible analysis would have error bars that, if you treat the problem linearly, would have put 0 and negative numbers within our error bars. I dutifully crunched the numbers and determined that the gravitational constant was something like 6.8m/s^2 and turned it in.

Naturally, I got a failing grade, because that's not particularly close, and no matter how many times you are solemnly assured otherwise, you are never graded on whether you did your best and honestly report what you observe. From grade school on, you are graded on whether or not the grading authority likes the results you got. You might hope that there comes some point in your career where that stops being the case, but as near as I can tell, it literally never does. Right on up to professorships, this is how science really works.

The lesson is taught early and often. It often sort of baffles me when other people are baffled at how often this happens in science, because it more-or-less always happens. Science proceeds despite this, not because of it.

(But jerf, my teacher... Yes, you had a wonderful teacher who didn't only give you an A for the equivalent but called you out in class for your honesty and I dunno, flunked everyone who claimed they got the supposed "correct" answer to three significant digits because that was impossible. There are a few shining lights in the field and I would never dream of denying that. Now tell me how that idealism worked for you going forward the next several years.)

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1. analog31 ◴[] No.43552066[source]
I'm certainly not going to defend your teacher or your experience, especially at the high school level. That's too soon. And I also remember being indignant for a similar experience in analytical chemistry.

But... there's a point in one's development as a science student, where science becomes more nuanced than "doing your best and honestly reporting what you observe." Those things will always be there of course. But in an experimental science, doing an experiment and getting accurate results is a vital skill, or you'll never make progress.

Naturally you have no standard for checking a measurement whose result is truly unknown, but you can insert the equivalent of breakpoints where you make sure that the same data do reproduce known results. Ironically for the discussion here, those are called "gravity tests." Students need to know at some point if they're going to like the experimental side of science. Getting things right is part of it. Some people don't belong in the lab.

I happen to be stuck at the "gravity test" level in my day job. My experiment produced a calibration that's reproducible, and that I could use, but it doesn't make sense. I'm not going to move forward until it does.

The problem with a lot of teaching is that the purpose of the lesson is never explained, and the nuanced view is never spelled out.