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A Teacher Incentives Story, In Honor Of Mothers’ Day…

May 11th, 2009 · 1 Comment
Incentives

I love my mother. I also find my mother pretty amusing- today she decided to chide me for my use of (arguably marginal) curse words on Twitter (which I will forgive her for since, hey, whose mom follows them on Twitter?), and for some reason this was the funniest thing of the day, even beating watching David Ortiz swing a pink bat in honor of mothers’ day.

For context, my mom is a high school English teacher in Florida. (She is kind enough to not correct my grammar, lest I point out that one time when she spelled tomato wrong in a recipe she wrote for me.) Teachers in Florida have been guinea pigs for a number of incentive experiments in recent years, and my mom reports back to me on the ones that she finds interesting/frustrating/etc. Behold:

“My kids just finished the AP Lit test, so it made me think about the $50 bonus (bounty) paid for each passing student— caps at $2000. (I maxed out last year–yay!) How much does that impact on teacher—or even student performance—in class or on test? Some of us (not mentioning any names–me) work on the “how many of these yahoos can I really get through this test? Can I top last year? concept, not monetary rewards. Not that I’m sending the check back! 🙂

Mommie”

My mom comes dangerously close to giving supporting evidence to those people who argue that underpaying teachers is okay because they aren’t doing it for the money. That aside, I find a number of things interesting about the incentive system that she describes:

  • Test-based teacher incentives are generally problematic because incentives can only be given for what can be measured, i.e. test scores. That said, AP classes are perhaps one of the few places where teaching to the test is not so bad, since the test is pretty representative of what students were supposed to learn in the courses.
  • In Florida, the state pays for students to take AP tests. When I was in high school the cost of an AP test was somwhere in the neighborhood of $79. So the bonus to the teacher for a passing student is smaller than the cost of the test itself. Just putting things into perspective here.
  • What counts as passing? FYI, the AP test is scored on a normalized 1-5 scale, with a 3 technically considered passing (even though a lot of colleges won’t accept scores of 3 for credit). With the system described, there is no specific incentive for teachers to push students to get 4’s or 5’s.
  • My mom’s “can I beat last year?” point is food for thought. Incentives for people such as hedge fund managers are often based on comparison to a high-water mark, so that only improvements on previous performance are compensated. This seems like a potential way to offer more high-powered incentives in order to get marginal students across the passing threshold (since the school board could offer several hundred dollars for each additional student over last year with no increase in expenditure for the system), but could result in gaming of the system at time zero, since a good way to see improvement is to suck it up in the first year.
  • The cap on the bonus implies that teachers only get compensated for the first 40 passers. My mom, for example, has 2 AP classes (I think), so she probably has between 50 and 60 students. If teachers actually respond to the incentive given, there is actually a negative peer effect in the classroom- if there are 40 really smart kids that will definitely pass, why not just let the others fall by the wayside? (For the record, my mom teaches at my old high school, and as I recall there was always a critical mass of high-performing students- including a certain Dan L who shows up here- that would pass regardless of what the teachers did. This is not to say that mom is not awesome at her job, but it does lessen the incentive to try, to a degree.) I am curious as to what the justification for the cap is, since the system is effectively giving stronger incentives to those teachers with fewer students, when logicially the opposite should probably be the case.

I think that last point deserves a diagram:

(I was watching Important Things With Demetri Martin as I was making that graph. It made me happy. The Daily Picture section on that link will make you happy.)

Tags: Incentives

1 response so far ↓

  • 1 GeekTeacherMom // May 11, 2009 at 4:21 pm

    As a statistics and economics instructor of undergraduates let me validate your illustration by pointing out that where the arrow points does indeed look like a leftward bent child (actually prospective student’s behind). If only you’d drawn the sagging pants.

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