Tuesday, September 25, 2018

How To Infuriate With Scales

The University of Chicago Law School's grading scale goes from 155 to 186.

For awhile, it was 55 to 86, but employers kept assuming that our tip-top students were actually getting middle-to-low Bs. So they added a "1" to it, on the theory that completely opaque is better than affirmatively misleading.

Of course, within that 155 to 186 range, we still break up grades into the traditional As, Bs and Cs (180 - 186 is an A, 174 - 179 is a B, and so on). So the actual choice of numbers in the scale is pretty much arbitrary -- as the casual introduction of the "1" aptly demonstrates.

I was thinking about this while reading a story of a Florida teacher who was, the headline tells us, "fired for refusing to give students credit for homework not turned in". District policy was to give a 50 for unsubmitted homework; the teacher instead gave such assignments a zero, and so she was terminated.

The story is meant to be a lesson about participation-award style administrators and overly entitled post-millennial brats expecting credit even where they didn't do any work. As the teacher put it, "we have a nation of kids that are expecting to get paid and live their life just for showing up and it's not real."

But I read the story and just thought "aren't they just making a 50 a 0?"

The thing about the traditional 0 - 100 grading scale is that pretty much nobody uses the entire scale. As are (roughly) 90 - 100, Bs 80 - 89, Cs 70 - 79, Ds 60  - 69, and Fs -- a failing grade -- are anything below that, but for all intents and purposes 50 - 59. The bottom half of the scale is pretty much never used (save for something like right/wrong multiple choice tests -- but even those are frequently curved up). I don't think I've ever given a grade between 1 and 49 in my entire life.

So, in effect, the district's policy is simply formalizing what is probably already the functional practice: a grading scale of 50 - 100, where 50 is the lowest grade (reserved for, say, not turning in the assignment at all, or otherwise completely bombing it). Making 50 the bottom of the scale isn't any different (and doesn't represent any more coddling) than placing the bottom at 55, or 155.

Indeed, I think the formal 50 - 100 scale is just better. Assuming I'm right that the bottom half of the 0 - 100 scale is never used except for zeros in the case of simply not doing the assignment, then the primary function of that scale is to massively overweight not turning an assignment (getting a 0) as compared to failing it for another reason (which, presumably, would earn you between a 50 and a 59). It's the equivalent of a five letter grade difference. Whether that's appropriate or not is a normative question, and while I don't think it is beyond argument my instinct is to treat failing grades roughly alike. There is a difference between simply not turning in an assignment and turning in a failing quality assignment, but for me that difference exists inside the bandwidth of a normal F grade (it's the difference between, say, a 50 and 58).

But I doubt that the normative dispute is actually driving anything. I'd wager that all the sense of outrage here is an artifact of the perceived scale -- the idea that students are still getting "credit" for undone work -- which is based on the misapprehension that the numbers on the scale translate into some sort of objective percentage. The advantage of a 155 to 186 scale is that it doesn't delude anyone into thinking it represents anything but an a set of more-or-less arbitrary markers denoting cut-offs between As, Bs, Cs, Ds, and Fs.

Likewise, if the district announced it was switching to a 0 - 50 grading scale (where 0 - 9 is an F, 10 - 19 is a D ... etc.), I doubt anyone would care -- even though it was mathematically doing the exact same thing as having a 50 - 100 scale. Ditto if the scale was 25 - 75, or if it was 0 - 100 but every 20 points represented a different grade (so 80 - 100 was an A, 60 - 79 a B ....). None of those are actually different from one another, and none, I think, would provoke any sort of outrage.

Of course, things are probably not quite that neat (especially if the district hasn't abolished below-50 grades outright). Still, I wonder if the teacher -- so aggrieved at being forced to "give credit" for incomplete work -- actually understands that the real issue here isn't about objective "credit", but about arbitrary scales. I don't want to say she doesn't -- I don't have enough information to conclude that -- but the story as presented doesn't make me wholly confident that she does either.

No comments: