Time Banking IV: The Role of the OraclePosted: June 14, 2012
I’ve never really gone into much detail on how I would make a system like Time Banking work. If a student can meet my requirements and submit their work early then, obviously, I have to provide some sort of mechanism that allows the students to know that my requirements have been met. The first option is that I mark everything as it comes in and then give the student their mark, allowing them to resubmit until they get 100%.
That’s not going to work, unfortunately, as, like so many people, I don’t have the time to mark every student’s assignment over and over again. I wait until all assignments have been submitted, review them as a group, mark them as a group and get the best use out of staying in the same contextual framework and working on the same assignments. If I took a piecemeal approach to marking, it would take me longer and, especially if the student still had some work to do, I could end up marking the same assignment 3,4, however many times and multiplying my load in an unsupportable way.
Now, of course I can come up with simple measures that the students can check for themselves. Of course, the problem we have here is setting something that a student can mis-measure as easily as they measure. If I say “You must have at least three pages for an essay” I risk getting three pages of rubbish or triple spaced 18 point print. It’s the same for any measure of quantity (number of words, number of citations, length of comments and so on) instead of quality. The problem is, once again, that if the students were capable of determining the quality of their own work and determining the effort and quality required to pass, they wouldn’t need time banking because their processes are already mature!
So I’m looking for an indicator of quality that a student can use to check their work and that costs me only (at most) a small amount of effort. In Computer Science, I can ask the students to test their work against a set of known inputs and then running their program to see what outputs we get. There is then the immediate problem of students hacking their code and just throwing it against the testing suite to see if they can fluke their way to a solution. So, even when I have an idea of how my oracle, my measure of meeting requirements, is going to work, there are still many implementation details to sort out.
Fortunately, to help me, I have over five years worth of student data through our automated assignment submission gateway where some assignments have an oracle, some have a detailed oracle, some have a limited oracle and some just say “Thanks for your submission.” The next stage in the design of the oracle is to go back and to see what impact the indications of progress and completeness had on the students. Most importantly, for me, is the indication of how many marks a student had to get in order to stop trying to make fresh submissions. If before the due date, did they always strive for 100%? If late, did they tend to stop at more than 50% of achieved marks, or more than 40% in the case of trying to avoid receiving a failing grade based on low assignment submission?
Are there significant and measurable differences between assignments with an oracle and those that have none (or a ‘stub’, so to speak)? I know what many people expect to find in the data, but now I have the data and I can go and interrogate that!
Every time that I have questions like this about the implementation, I have a large advantage in that I already have a large control body of data, before any attempts were made to introduce time banking. I can look at this to see what student behaviour is like and try to extract these elements and use them to assist students in smoothing out their application of effort and develop more mature time management approaches.
Now to see what the data actually says – I hope to post more on this particular aspect in the next week or so.