Posted by tpc at May 25th, 2008
The sad truth is that many of the students in the university are not here for an education. They are here to socialise, play freesbies in the field, run hall activities and yes get a degree. While some still attend classes, many subscribe to the mantra “studying worked solutions will help them pass exams”. To a certain extent, it becomes a self-fulfilling prophecy because the university do not want to fail too many students, and given that the students did not work hard to learn, the only way to let them pass is to set exams which resembles tutorial questions and provide clear written solutions to tutorial questions.
Now in my view, studying solutions to sample problems is really not a pedagogical sin. Well at least not in mathematics. One very important aspect of learning mathematics is mimicking carefully selected examples. But that is only the start. A student need to move on to the next stage of actually solving problems on their own. Many never do.
Because I do not want to adopt the high handed approach of failing 70% of the class, I intend to assign homework for my courses next semester. Simply put, it is to force students to do work which they are supposed to do on their own but never get round to it. Homework is not a popular activity, although the dept has recently made it mandatory for certain courses - a good sign. It requires a lot of extra effort in assigning problems, writing clear solutions, collecting, collating marks and worst of all, marking. Fortunately, we have graders to help us do the latter.
But collecting homework brings with it a new problem. Plagiarism. Some pretend it doesn’t happen, which is the easy way out since if we catch students we also need to go through the difficult process of discipline. Yet, it becomes a farce if the homeworks are merely copied, which renders everything completely meaningless. I especially pity the graders. (Although the graders might actually like to grade 100 copies of the same assignment.)
The university has licensed a system called turnitin, and I attended a talk by a chemistry lecturer who shared his experience. I really appreciated that. The surprising(?) result is that he had a chart that says almost 50% of the lab reports had been plagiarised. Now, the 50% can be interpreted in many ways, but it does sound high. The twist to the story is that the students knew they had to submit their report to plagiarism checking. So they could in theory, lift a passage from wikipedia, changed the adjectives, rearrange the sentences and escape detection. I do not believe the engine is that smart yet. But it turned out that those reports submitted early was not flagged, but those that were submitted later were flagged. The revelation is that many copied from past year reports from seniors which were not in the database of turnitin but were flagged because their classmates who submitted earlier had the same answers.
But with mathematics, I don’t think turnitin will work. For example, in those chemistry lab reports, an example was that when there were exponents like “x 10-5″ , it got flagged. Plus, if I wanted typed reports, I’d get ms word documents! And most important of all, I wouldn’t be surprised if original solutions to mathematical problems look identical.
I’m still thinking of a good way to implement this. I might try turnitin if I decide to ask the students to write some essays on mathematics history, if that day ever comes.
to the numerator and denominator for each of the 3 angles. Use the double angle formula for sine and then cancel away with 
that indeed the equation is one of three series that appeared in Ramanujan’s work “Modular equations and approximations to 
” Naturally, I went back to the web and this time hit the jackpot. Two screencaps:
. Then the magician asks the participant to add the five numbers 
and 
, and reveal their sum. Suppose the sum was 3194. What was 
.
. Take the smallest multiple larger than the given number, and check by subtracting the difference and summing the digits. You do not have to do it with more than 5 different multiples. 
.
, so incorrect.
.
and we found our number. 
, for Lucas numbers.
