This is a follow-up post from this post in which I unpicked one part of large education review. In that post I covered aspects of papers by Vardardottir, Kim, Wang and Duflo. In this post I cover another papers in that section (page 201).
Booij, A.S., E. Leuven en H. Oosterbeek, 2015, Ability Peer Effects in University: Evidencefrom a Randomized Experiment, IZA Discussion Paper 8769.
- In two-way tracking lower ability gain a little bit (10% significance in my book is not significant), higher ability gain a little bit (borderline 5%)
- Three way tracking: middle and low gain some, high doesn’t.
- Track Low: low gains, middle more (hypothesis less held back?), high doesn’t.
- Track Middle: only middle gains (low slightly negative but not significant!)
- Separate high ability: no one gains.
This is roughly the same as what is described in the article on page 20. The paper then also addresses average grade and dropout. Actually, the paper goes into many more things (teachers, for example) which I will not cover. It is interesting to look at the conclusions, and especially the abstract. I think the abstract follows from the data, although I would not have said “students of low and medium ability gain on average 0.2 SD units of achievement from switching from ability mixing to three-way tracking.” because it seems 0.20 and 0.18 respectively (so 19% as mentioned in the main body text). Only a minor quibble, which after querying, I heard has been changed in the final version. I found the discussion very limited. It is noted that in different contexts (Duflo, Carrell) roughly similar results are obtained (but see my notes on Duflo).
Overall, I find this an interesting paper which does what it says on the tin (bar some tiny comments). Together with my previous comments, though, I would still be weary about the specific contexts.