The week’s session of Understanding Educational Research included the great online primer to research design by Trochim. Before diagramming the various designs in articles we had found, we reviewed the classic models:
The controlled, randomized experiment:
R O X O
R O O
The quasi-experiment:
O X O
O O
The longitudinal study:
O O O O
And, of course, the non-experiment:
X O
As we discussed the strengths and weaknesses of each model, we tried to think of research purposes for which each design was suited. Of course, only one of these model can by itself establish causality, which is why it is the “gold standard” of educational research. Both quasi-experiments and longitudinal studies are useful for establishing trends and formulating hypotheses (which are then tested with the first model), but what about that last model?
The non-experiment is pretty much useless. Sure, you give some treatment and you gather some data, but one of two fatal flaws lingers: 1. Either the point of the study was to reveal something about the treatment, but, without a pretest, we can’t say anything about it; or 2. the treatment wasn’t the focus of the study, in which case it shouldn’t be part of the design.
Towards the end of our discussion, one of the literacy masters students shouted, “The treatment is irrelevant!” I thought that was so astute that I added it to the slide with an APA-formatted citation to the student’s comment.
The students, most of whom are in-practice teachers, saw this two slides later:
Teacher Evaluations → X O
A study that claimed to establish the effect of any treatment without at least a pre-test would have a hard time getting published in an academic journal. Yet that is the model we’ve been using for ten years to determine whether teachers, schools, districts, and states are effective.
Some states have moved to the “growth model” for teacher evaluations, which would look like this:
O X O
The major improvement with this model is that we can now establish the change that occurred during the treatment period. On the other hand, it does not tell us the degree to which the treatment was responsible for the observed change. This model is still not appropriate if its results are to be used to hold individuals and groups accountable.
It is becoming sadly commonplace to see policymakers misuse social science methods, but, in this case, there is also a high degree of hypocrisy: At the same time state offices of education have attempted to discover teacher effectiveness via research models that cannot produce such evidence, those same offices have called for teachers to use only “evidence-based methods” of instruction. It’s a classic case of do-as-we-say-not-as-we-do.