From: Raymond T. <toy...@gm...> - 2022-01-15 18:27:06
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On Fri, Jan 14, 2022 at 2:10 PM Barton Willis via Maxima-discuss < max...@li...> wrote: > > If (as is the case with many schools) there is a student survey after > the class is over, how will students react to questions about the > additional material? > > *Additional wandering:* For eight years, I served as a department chair > for a faculty of about fifteen at a hyphenated public university. As chair, > I saw 1000s of student evaluations and comments. Asking students to do > anything "unusual" (use TeX, explain something using two sentences, or > use a programming language in a course on statistics) is a fairly clear > path to lower teaching evaluations. I know this might seem cynical and I > know that humans are subject to huge amounts of confirmation bias, but I > informally collected this data. > Interesting. I was very happy to use SPSS or whatever it was in my stats class in college. I hated doing ANOVA and stuff like that by hand. > > Generally, I do not reveal to students that I sometimes contribute to an > open source computer algebra system, and that I donate a bit of my time > helping people around the globe to use it. I teach a fairly traditional > calculus class. > > As for cheating during an online math exam, it's the second pandemic. Of > course, we can simply change our notion of cheating. A popular option is > to mostly abandon exams in favor of experiential learning, group work, and > activities. We like to ignore the fact that academic research shows that > group work often puts introverts at a disadvantage. > I generally hated group work. Perhaps because I'm a bit introverted, but mostly because everything took much longer than it should have. At my college we had self-study classes supposedly to let students learn at roughly their own pace and perhaps help them do better. There were still tests, and you had to finish a certain amount of material. I just tried to go as fast as possible and learned just enough to get a good grade. (You can retry different tests as many times as needed, with a delay between retries). I think in the end, I ended up cheating myself because I didn't remember anything afterwards. Fortunately, these classes weren't really required for later classes (or at least the classes I ended up taking later). > > Some say that they can construct questions, such as tell me the next step > in the calculation, to combat cheating on online exams. I don't think this > is a particularly good solution--my steps might not be your steps. And > unless the long list of questions at the end of each section are changed to > tell-me-the-next step variety, I think it's not a fair way to test > students. > > --Barton > ------------------------------ > *From:* Richard Fateman <fa...@gm...> > *Sent:* Friday, January 14, 2022 14:57 > *To:* Eduardo Ochs <edu...@gm...> > *Cc:* <max...@li...> < > max...@li...> > *Subject:* Re: [Maxima-discuss] A question about parsing: ":lisp #$expr$" > is not low-level enough > > Non-NU Email > ------------------------------ > This is going to wander quite a bit from the original question, but here > goes. > > We see proposed usages like Eduardo's from time to time, and there are > more or less a bunch of questions that come up, especially > in the context of enthusiastic teachers assuming technology is good for > the students. So here are some > thoughts. > 1. It is possible to use Maxima and similar programs as essentially > typesetting assistants. That is > you type something in, and you get something displayed. The fact that you > type in a+x and it displays > x+a is unacceptable, and so you start on workarounds. Some people use > "a+x" or turn off simplification etc > > This can work, but it MAY miss a significant point or two. These have come > up previously, and the > answers are kind of squirmy. > > 2. what part of your curriculum is 'students learn the input syntax of a > computer algebra system'; > 'students become proficient in typing mathematics [on a phone:? on a > keyboard?] > > 3. And if a student asks, > 'Is this going to be on the final?' you might have to say, no, there will > be no computers then. > > 4. Beyond the input syntax issue, there is 'what does it mean to > evaluate/substitute/simplify ... in the context of > a computer algebra system? Is this on the final? > > 5. if a computer can do differentiation, integration, solve equations, > plot functions... why should I have to > do this? Isn't this showing that this course is even more unimportant that > I thought? > > When I taught a calculus+ computer algebra course many years ago, the > students were far more curious about > how the computer did the integration problems than anything else. These > were high-end students though. > > Low end students will, most likely, want to get a passing grade in > calculus with the least effort, and then will > thoroughly forget whatever material they absorbed. They may also be > inclined to cheat, especially when > examinations are so hard to proctor over zoom. If (as is the case with > many schools) there is a student survey after the class > is over, how will students react to questions about the additional > material? They have enough trouble with > understanding what a "function" is, without being confused by computer > languages and such. So they may give > the instructor (you...) a low rating. > > There is a scant literature on this, and I haven't looked at it in some > years, but when the question is posed as to > whether students learned calculus better with a computer lab, the answer > has been: no, they did not learn > better. No, by and large they did not enjoy the (substantially enriched) > technical material. Maybe there is > different evidence today in support of using computers. Maybe it is > possible to run a course without a human > instructor -- just "learn calculus in 25 easy lessons, online"? > > It is not my intention to discourage people from trying innovative ideas > so much as to look at them critically. > "Putting it on the computer" is not always a win. > > > oh, two quick items: > v:a+x$ > ?subst(43,a,v); ==> x+43 > > ?subst( 43,x, x + 'integrate(f(x),x)) ==> integrate(f(43),43)+43 > which is, logically, bonkers. The x inside integrate is a 'bound > variable'. > > If you want to teach this, good luck. Is it related to "what does the > 'd' mean in integral(f dx) ? And what does the space between f and d mean? > Is it multiplication? > Have fun. > Cheers > Rjf > > > > > > > On Thu, Jan 13, 2022 at 10:00 PM Eduardo Ochs <edu...@gm...> > wrote: > > Nifty!!!!!!! =) =) =) > > My use case is very atypical. In my classes I have many students who > have very little practice with using variables - really! It's sad & > scary - and when these students have to take a formula and perform a > substitution on it to obtain a particular case they usually make a big > mess... for example, they often substitute only certain occurrences of > the variables, and leave the other ones unsubsituted. And when they > have to perform substitutions on theorems, propositions, or proofs the > mess is even bigger... > > So: I'm trying to teach them that substitution and simplification _can > be treated_ as separate operations, and when we keep them as separate > steps our calculations become much easier to debug... We're doing that > on paper, and I told them that I believe that all decent programs for > Computer Algebra should be able to perform substitution in a purely > syntactical way, without simplification, _if we call the right > low-level functions in them_. With your trick I'm almost there... try > this: > > simp:false; > to_lisp(); > (defun $displr (lambdaexpr) (displa (caddr lambdaexpr))) > (to-maxima) > q: lambda([foo], ('integrate(f(x), x, a, b) = F(b) - F(a))); > displr(q)$ > displr(subst([a=42, b=99], q))$ > displr(subst([a=42, b=99, f(x)=3*x^2, F(x)=x^3], q))$ > displr(subst([a=42, b=99, f(x)=3*x^2, F=lambda([x],x^3)], q))$ > > In the last two lines I'm trying to replace all occurrences of F(expr) > by expr^3, but I haven't found the right trick yet... > > Cheers and probably thanks in advance =), > > Eduardo Ochs > http://angg.twu.net/eev-maxima.html > <https://urldefense.com/v3/__http://angg.twu.net/eev-maxima.html__;!!PvXuogZ4sRB2p-tU!Uiy9-wA6d-agkixNbW5Pr5RtNxWANcdbjDny63-pmyVEanMZ6muQnFAuKjQlmas$> > > On Thu, 13 Jan 2022 at 11:11, Stavros Macrakis <mac...@al...> > wrote: > > Simplification does not happen as a separate step after evaluation of the > whole expression. > Every subexpression that is evaluated is immediately simplified. Maxima > couldn't possibly work otherwise. > > Obviously we need to be review our documentation more carefully to keep > such howlers out! > > Using :lisp #$ ... $ seems pretty roundabout. To turn off simplification, > set *simp:false*. To prevent evaluation, use *'( ... )*. To show the > internal form of something, use *?print(...)*. > > Here's a neat trick: within *lambda* expressions (as well as named > function definitions), neither simplification nor evaluation is performed, > so *q: lambda([simp], ?print(2+2)) *might help you see how things work; > look at *q*, and call *q(false) *and *q(true)* . > > _______________________________________________ > Maxima-discuss mailing list > Max...@li... > https://lists.sourceforge.net/lists/listinfo/maxima-discuss > -- Ray |