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Re: [Phys-L] book versus video versus lecture



On 01/10/2014 12:55 PM, Donald Polvani wrote:

I think video based courses can be just as effective, or even more effective
than live lectures, if they are "well done" and the students are motivated
to learn the material

I reckon that if the students are sufficiently motivated, almost
any technique will work. R.T. describes a situation where an
attractive video is effective when the students are initially /not/
very well motivated.

In any case, we agree that "well done" is super-important.

Professor Oppenheim
closely followed his text and started each lesson with the blackboards all
filled in. No time was wasted writing something on the board, and we
students didn't waste our time (and divert our attention) by taking verbatim
notes.

Indeed! Imagine an invited talk at the APS March meeting, or at a
university colloquium, and suppose the speaker showed up with no
prepared graphics and just scribbled a few things on the board. I
would be shocked. I would be wondering, is the guy just incredibly
lazy, or did somebody mug him on the way from the airport and steal
all his files?

I'm not suggesting that a classroom teacher who writes on the board
is lazy. Instead I am saying that the teachers are grossly underfunded
and overworked. This creates a system where the teacher doesn't have
time to prepare the way a colloquium speaker would prepare. The result
is tremendous inefficiency, including a big waste of students' time.
Students learn more and learn better if you're not wasting their time.

I attribute this to gross mismanagement. I've seen many examples of
bad management in my time, and the education system is pretty high up
on the dishonor roll. It is amazing to see smart people being so stupid.

I've shown plenty of video in my time. People ask, aren't you admitting
that the guy on the video is a better lecturer than you? Well, yes, the
guy in the video *is* a better lecturer, but that's not the point. The
point is that he has already done the work of creating lots of good
graphics. Given enough time, I could recreate all that, but that would
not be a good use of my time. If you guys have a question, raise your
hand and we'll stop the video and discuss it. That's a good use of my
time. Also, I disagree with about 5% of what the guy says, and that's
another good reason to stop the video every so often.

Bottom line: Video plus me gives you a better education than relying
on video alone. Relying on me alone might be better, but it would
be prohibitively expensive.

I am *not* hoping to see a set of videos that make the classroom
teacher unnecessary. Instead, it is more fun to imagine a set of
videos that make the classroom teacher more necessary, more valuable,
more able to do the things that teachers are good at.

One could imagine students watching videos outside of class, and
then using class time for discussion. This is related to the
trendy idea of "flipped classroom", but it is not even remotely a
new idea. The big university "service courses" have been using this
model for decades, since before video was invented, if you think of
the big lecture hall as being mainly a spectacle for the students
to watch, and you think of the small discussion sections as being
the real classrooms, and the TAs as being the real teachers.

==========

One thing I would like to see in educational videos is more hyperlinks,
i.e. more nonlinearity.

I've been writing technical stuff with hyperlinks since before Google
existed, and indeed since before the web was invented. One thing
that you notice is that people really like hyperlinks. It just
kills me to see MOOC videos where somebody asks a question and the
professor says "we will get to that at a later date". Well, why
is there not a button that hyperlinks to the appropriate discussion?

This requires nonlinear editing, i.e. waiting until the later chapters
are online and then going back over earlier chapters to insert links.

If given half a chance, people will learn stuff out of order, and
there are good reasons why they should. For starters, if there are
20 different things that students might or might not already know,
that right there creates a million different possibilities. It
guarantees that no two students will be alike. The first rule of
making a good presentation is "know thy audience" but that's a big
problem if the audience is heterogeneous. Hyperlinks lessen the
problem, insofar as students can skip the stuff they already know,
and replay the stuff that puzzles them.

It is pretty easy to read a book out of order. Books are better than
scrolls in this department, which is why Barnes & Noble doesn't sell
a lot of scrolls. A long video without hyperlinks or navigation
aids is not quite as bad as a scroll, but it still strikes me as a
pre-dark-ages approach.

Indeed, the idea of a long video strikes me as a bad idea. In most
cases, it would be better to have a whole bunch of short videos
... linked together in some high-dimensional nonlinear fashion.

====================

There is such a thing as an "ignition" problem:
-- If you heat the tinder to 100 degrees nothing happens
-- If you heat the tinder to 200 degrees nothing happens
-- If you heat the tinder to 300 degrees nothing happens
-- If you heat the tinder to 400 degrees nothing happens
-- If you heat the tinder to 500 degrees you get a fire.

If the objective is to start a fire, if you apply insufficient resources
to the problem, all the resources are wasted. This is another example
of gross managerial malpractice.

I mention this because good videos are very expensive to
produce. On the other hand bad videos are a huge waste of
resources, just as bad lectures are a huge waste of resources.

In contrast, a good video should pay for itself. If it gets
widely used, the cost per student is very very small. It's
an ignition problem: a half-baked effort is worse than useless,
but doing things right would be tremendously useful.

I see publishers as part of the problem. They "should" be in a
position to apply resources to the problem, and reap the rewards.
They would be in a position to apply management skills, if they
had any.

You can semi-understand part of the problem: There are zillions
of people who would like to write a book. Therefore publishers
don't need to pay authors; they just sit there and let wannabe
authors pitch books to them. The problem is, the authors in
their garrets don't have enough resources to do a good job. So
there is a superabundance of (shall we say) highly imperfect books,
and no process for creating anything really good.

The same goes for educational videos, only more so, because the
production costs are so much higher.