Being a weblog devoted to a variety of topics. Including Mathematics. And Mathematical Finance. Sometimes with homework.

Friday, September 25, 2009

Presentation Points

Each homework problem is graded on a scale of 7 points for correctness and 3 points for presentation. The purpose of grading on presentation is to encourage students to write solutions to problems in a way that another person who had not done the problem themselves could understand the solution. This is an extremely important skill, not just for mathematicians but in all walks of life where mathematical conclusions need to be explained to supervisors, clients, inspectors, and such.

But it can be pretty subjective if we just say it's a score for "presentation". So I'll explain what my grading philosophy on this is.

All differential-equations-related steps are to be identified in words. Examples of this would be attempting to separate variables, multiplying the equation by an integrating factor, or plugging in the initial conditions to solve for a constant of integration. You will learn other techniques during this course that will have to be identified similarly.

Some calculus steps should also be identified in words, such as u-substitution or trig-substitution to solve an integral, or differentiating to find a maximum or minimum point. You don't have to explain that the derivative of sine is cosine, or that you can pull a constant out of an integral.

Very few algebra or arithmetic steps need to be identified. Finding the roots of a polynomial or doing a partial fraction decomposition are the only ones I can think of off the top of my head.

So this is how points will be awarded:

3: All the above steps are identified using words.
2: A significant proportion of the steps that should be identified using words are not, but it is immediately clear to me what the student is doing.
1: A significant proportion of the steps that should be identified using words are not, and it takes some effort on my part to comprehend what the student is doing, due to minor steps being omitted, extremely unclear or incorrect notation, or the work being scattered around the page rather than flowing from top to bottom and right to left.
0: Vital steps are completely missing from the solution, or the problem is not attempted at all. Note that this may also affect the correctness score. I also reserve the right to give 0 points in special cases at my discretion, for instance if a problem requiring significant mathematical work is answered with an incorrect solution that requires little or no work. I don't want to give out zeros, trust me.

If a problem has multiple parts, with different presentation quality among the parts, the score will be a rough average of the presentation score for each part.

Following the above simple presentation rules gives all students the opportunity to get points that may make up for minor errors in the solutions themselves. Please take advantage of that opportunity.

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