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Re: grade inflation, etc.

Obviously I need to recheck what I remember of Darwin. Meantime, would
you
provide other examples of my hyperbole?
One counter-example is worth 1 trillion examples (and then some)

In other words, you don't have any more examples?

Your statement regarding example may apply to physical theories (maybe not;
one bad data point doesn't invalidate the curve), but it doesn't apply to
historical generalizations.


Can you justify your statement that "physics is a form of
communication?"
Certainly most of us find that it involves communication, but that's a
long
way from being a form of communication.

Physics is how we communicate our experience of nature.

So if one makes advanced discoveries in natural law, but communicates them
to no one, one has done no physics? I disagree. It's not for me to define
physics, but I think it's entirely possible to practice physics and be very
competent at it without putting one's findings in writing, just as it's
possible to play music without an audience.

The students I referred to earlier as not writing up the labs are often
superb communicators. They just see no point in writing up a lab so I can
read results I already knew. Many of them seem to see my judgment of their
learning and ability as irrelevant to their learning.


Wrong question. Can I reliably assign a grade that predicts
a student's future performance in an engineering environment
or in an advanced academic setting? Yes. People have been
doing it for generations.

I'd like to see some evidence for that claim. All of the studies I've
heard of with grades as a predictor indicate them to be very poor.




Suppose I have two students who work together in a lab. One student
understands the purpose of the lab better, figures out what equipment
to
use and how to set up the lab in order to give good results, analyzes
the
first set of data, and on the basis of the results proposes a second
experiment to investigate a trend in the data. The other student
contributes to the lab, but clearly doesn't have the understanding of
the
physics that the first student does. The first student doesn't turn in
a
lab report; the second one does. Which one has better ability to
"perform
physics?"

Since I have no idea of what your labs are, or how you determine
how well a student "understands the purpose of the lab", the
question is unanswerable.

Some examples:

Measure the speed of sound to within 1% of the accepted value--no
procedural directions whatever are given.

Pendulum swings and thread is cut by a razor. Where will the bob land?

Given the Young's double slit equation, a double slit of known separation,
and a laser, determine the wavelength of the laser. (Mathematically easy;
procedurally difficult in a classroom with 10+ other lab groups and the
lights out most of the time).

Using a cart that drips water, at regular time intervals, predict what
graphs of position vs time and velocity vs. time will look like for the
cart.

Plus a number of others, some cookbook, some not.

The typical student of the type I have in mind for the above labs will
consistently grasp the relationship of the apparatus to the stated
objective, or figure out what kind of apparatus is needed to take what kind
of measurements; will show a strong understanding of how precise
measurements need to be to get good results; will take great care in
setting up the equipment and reading data so as to get good results; will
do a quick analysis with a calculator to see if results are matching
anticipated results; will show a much better ability to deal with equipment
they've never seen before, such as voltmeters and ammeters; and will
communicate clearly to lab partners what they think and why. They just
have better things to do than write up a lab report about stuff they
already know.

The typical partner of this student is very bright, often academically
motivated and interested in what's going on, and has a high GPA, but not in
the other student's league.

So which one has better ability to "perform physics?"

I've also had extraordinary kids who are extremely theoretical but don't
particularly like labs, and will throw themselves at any intellectual
challenge with abandon.

I do know that AP exam grades are
effective identifiers of outstanding students, which is why
I try to validate my own judgment by giving old AP exams as
finals.

I've done similar things. Most of the students I'm thinking of have done
quite well on AP tests, and on IB tests, and on my tests. On IB tests,
where "internal assessment" counts for 24% now (used to count for 20%),
these kids often have 6's and 7's (highest possible score) despite getting
single-digit internal assessment scores. I once told one of them, "I
didn't know it was possible to get a 6 with your lab score."