Inkblots and Opportunity Costs: Pondering the Usefulness of VAM and SGP Ratings
I spent some time the other day, while out running, pondering the usefulness of student growth percentile estimates and value added estimates of teacher effectiveness for the average school or district level practitioner. How would they use them? What would they see in them? How might these performance snapshots inform practice?
Let’s just say I am skeptical that either VAMs (Value Added Models) or SGPs (Student Growth Percentiles) can provide useful insights to anyone who doesn’t not have a pretty good understanding of the nuances of these kinds of data/estimates & the underlying properties of the tests. If I was a principal, would I rather have the information than not? Perhaps. But I’m someone who’s primary collecting hobby is, well, collecting data. Th
