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The most common errors in undergraduate mathematics

math.vanderbilt.edu

81–90 of 117 posts

Re: The most common errors in undergraduate mathematics

#81
post #66
post #57

Earlier quoted context omitted.

Mathematicians still fight college building committees and IT people to get blackboards in newly-built classrooms. (Why IT people? Dust + classroom computer system/projector/etc.)

What about white boards?

You don't have to pick up a dozen pieces of chalk in order to find one that sort of works if you hold it just right.

Re: The most common errors in undergraduate mathematics

#82
post #50

Earlier quoted context omitted.

It seems tempting to have a single unambiguous notation for mathematics. But In constructing such a language, one will quickly realize that doing mathematics becomes an intensely arduous task. This is not unlike recent discussions about the conlang Ithkuil on HN. For better or for worse, math notation has for the most part been optimized for writing on paper or a blackboard, using context to eliminate "inessential de…

> Have you ever attempted to write Lisp on a blackboard What's a blackboard? Seriously, blackboards are pretty obsolete technology. Designing a notation to optimize for blackboards in this day and age is kind of like designing roads to accommodate horses.

Different communication mediums are better / worse for different tasks. Lisp might be great for formally writing something down, where you want to have zero ambiguity. That's not the way human conversation works though, we are always eliding details based on the context in order to communicate quickly.

The blackboard is no different - it's not the perfect way to communicate ideas but it let's us communicate ideas quickly.

Re: The most common errors in undergraduate mathematics

#83
post #50

Earlier quoted context omitted.

> Have you ever attempted to write Lisp on a blackboard What's a blackboard? Seriously, blackboards are pretty obsolete technology. Designing a notation to optimize for blackboards in this day and age is kind of like designing roads to accommodate horses.

There are two situations which black/white boards are awesome for. -Giving lectures in subjects which desperately need drawing and writing. Look at what happens at 1:16:27 here https://www.youtube.com/watch?v=BPSEpDq6QYc The speaker can just go draw a picture, in response to a question. I know of no alternative which can do something like that nearly as well. -Collaborating in subjects which need drawing and writing.…

Look, I have nothing against blackboards, just as I have nothing against horses. Horses are really handy in some situations. If you're in the wilderness and you need to cross a stream, a horse can be just the thing. There's no technology that can compete with a horse in that case.

But to constrain your infrastructure (notation in the case of mathematics, roads in the case of horses) according to the needs of a blackboard or a horse is, IMHO, a serious mistake in this day and age. If you design your roads for cars instead of horses you get tremendous productivity boosts, even as you lose the ability to deal with some edge cases.

Notice that to find an example of the real utility of a blackboard you had to bypass >95% of the lecture and go to the very end. Imagine how much better things would be if the rest of the lecture had been presented as source code that a student could analyze and manipulate and error-check using some automated tool.

Re: The most common errors in undergraduate mathematics

#84
post #52

Earlier quoted context omitted.

Lots of people, particularly people who do lots of math, still communicate with each other over a whiteboard.

Because their notation is optimal on whiteboards and onerous on computer screens.

Computer screens are also not optimal for collaborative discussion.

Re: The most common errors in undergraduate mathematics

#85

I studied undergraduate mathematics, and I think it's a field which requires the student to spend as much of their own time as needed to understand a concept. Perhaps this could be said of all fields, but there is just limited time in a class to absorb, e.g. Euler's Formula, because there are several concepts in play, and if the student doesn't have a firm grasp or recollection of one of them, then they get lost at o…

Perhaps this could be said of all fields, but there is just limited time in a class to absorb

Which brings us to that what can you expect to actually learn in a class anyway?

I'd say that for any non-trivial curriculum (which ought to include most of a university...) you need to read about the subject yourself and do your own learning. And once you do that where do you need the classroom? For asking questions, maybe? But a classroom probably isn't the most effective way to ask questions.

Re: The most common errors in undergraduate mathematics

#87
post #83

Earlier quoted context omitted.

There are two situations which black/white boards are awesome for. -Giving lectures in subjects which desperately need drawing and writing. Look at what happens at 1:16:27 here https://www.youtube.com/watch?v=BPSEpDq6QYc The speaker can just go draw a picture, in response to a question. I know of no alternative which can do something like that nearly as well. -Collaborating in subjects which need drawing and writing.…

Look, I have nothing against blackboards, just as I have nothing against horses. Horses are really handy in some situations. If you're in the wilderness and you need to cross a stream, a horse can be just the thing. There's no technology that can compete with a horse in that case. But to constrain your infrastructure (notation in the case of mathematics, roads in the case of horses) according to the needs of a blackb…

To constrain your infrastructure according to the needs of a computer is also silly. Imagine if, in order to hum a tune, one needed to write sheet music using a programming language. Or if every spoken conversation were halted the instant a word is used incorrectly.

Mathematics (and a lecture on mathematics) is closer in nature to a conversation than a road.

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Re: The most common errors in undergraduate mathematics

#88
post #80
post #66

Earlier quoted context omitted.

What about white boards?

I have no hard data on this, but dry-erase markers seem to be used up more quickly than chalk. Chalk is also less expensive. As one data point: 48 sticks of chalk for $4.30[1] versus 12 markers for $7.74[2]. I'm not sure about the bulk-price comparison, or if colleges can get dry-erase markers for cheap. Although, many of my professors carried their own supplies as markers left in rooms were usually stolen. There cou…

Crayola chalk is horrid. I gladly pay premium for well-made chalk (and I suspect most mathematicians prefer high quality chalk), which makes white board markers significantly cheaper.

Re: The most common errors in undergraduate mathematics

#89
I had a calc prof who spent most of a class lecturing on "RTFT," where the last T was Text Book instead of M for Manual because he thought somebody asked a stupid question.

To be fair, the question was kind of dumb. But the textbook was also worthless and created to generate revenue for the math department. So it's unlikely his proposed solution would have helped the student in question.

Not to mention that the lecture on RTFM didn't help anyone learn math anyway.

The student who asked the question probably never really understood the math (wrote learner), but did become the prof's office hour best friend and got a good grade anyway.

Anyway, file under the teacher hostility section of this article, I guess.

Re: The most common errors in undergraduate mathematics

#90
post #50

Earlier quoted context omitted.

> Have you ever attempted to write Lisp on a blackboard What's a blackboard? Seriously, blackboards are pretty obsolete technology. Designing a notation to optimize for blackboards in this day and age is kind of like designing roads to accommodate horses.

There are two situations which black/white boards are awesome for. -Giving lectures in subjects which desperately need drawing and writing. Look at what happens at 1:16:27 here https://www.youtube.com/watch?v=BPSEpDq6QYc The speaker can just go draw a picture, in response to a question. I know of no alternative which can do something like that nearly as well. -Collaborating in subjects which need drawing and writing.…

Computers can have pen input too for situations where that's more efficient, and for less expense than that lecture hall's complicated apparatus of multiple sliding blackboards to get around the finite drawing area limitation that computers don't have.
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