The Average of Noise is not Signal, It’s Junk! More on NJ SGPs

I explained in my previous post that New Jersey’s school aggregate growth percentile measures are as correlated with things they shouldn’t be (average performance level and low income concentrations) as they are with themselves over time.  That is, while they seem relatively stable – correlation around .60 – it would appear that much of thatContinue reading “The Average of Noise is not Signal, It’s Junk! More on NJ SGPs”

An Update on New Jersey’s SGPs: Year 2 – Still not valid!

I have spent much time criticizing New Jersey’s Student Growth Percentile measures over the past few years, both conceptually and statistically. So why stop now. We have been told over and over again by the Commissioner and his minions that New Jersey’s SGPs take fully into account student backgrounds by accounting for each student’s initialContinue reading “An Update on New Jersey’s SGPs: Year 2 – Still not valid!”

Rebutting (again) the Persistent Flow of Disinformation on VAM, SGP and Teacher Evaluation

This post is in response to testimony overheard from recent presentations to the New Jersey State Board of Education. For background and more thorough explanations of issues pertaining to the use of Value-added Models and Student Growth Percentiles please see the following two sources: Baker, B.D., Oluwole, J., Green, P.C. III (2013) The legal consequencesContinue reading “Rebutting (again) the Persistent Flow of Disinformation on VAM, SGP and Teacher Evaluation”

Briefly Revisiting the Central Problem with SGPs (in the creator’s own words)

When I first criticized the use of SGPs for teacher evaluation in New Jersey, the creator of the Colorado Growth Model responded with the following statement: Unfortunately Professor Baker conflates the data (i.e. the measure) with the use. A primary purpose in the development of the Colorado Growth Model (Student Growth Percentiles/SGPs) was to distinguishContinue reading “Briefly Revisiting the Central Problem with SGPs (in the creator’s own words)”

Video Thoughts on Test Scores, VAM, SGP & Teacher Evaluation

Recent Bank Street College of Education Symposium on teacher evaluation Additional video clips from legislative forum at the New Jersey Principals and Supervisors Association General Issues in Teacher Evaluation: Where to Start in New Jersey http://www.youtube.com/watch?v=5B7gAkB5-QU&feature=player_detailpage#t=1208s Pilots versus Expedited Legislated Evaluation Models (Rigidity of Legislation) http://www.youtube.com/watch?v=5B7gAkB5-QU&feature=player_detailpage#t=1878s Complete Forum Video:

If it’s not valid, reliability doesn’t matter so much! More on VAM-ing & SGP-ing Teacher Dismissal

This post includes a few more preliminary musings regarding the use of value-added measures and student growth percentiles for teacher evaluation, specifically for making high-stakes decisions, and especially in those cases where new statutes and regulations mandate rigid use/heavy emphasis on these measures, as I discussed in the previous post. ======== The recent release ofContinue reading “If it’s not valid, reliability doesn’t matter so much! More on VAM-ing & SGP-ing Teacher Dismissal”

Firing teachers based on bad (VAM) versus wrong (SGP) measures of effectiveness: Legal note

In the near future my article with Preston Green and Joseph Oluwole on legal concerns regarding the use of Value-added modeling for making high stakes decisions will come out in the BYU Education and Law Journal. In that article, we expand on various arguments I first laid out in this blog post about how useContinue reading “Firing teachers based on bad (VAM) versus wrong (SGP) measures of effectiveness: Legal note”

Piloting the Plane on Musical Instruments & using SGPs to Evaluate Teachers

I’ve posted a few blogs recently on the topic of Student Growth Percentile Scores, or SGPs and how many state policymakers have moved to adopt these measures and integrate them into new evaluation systems for teachers. In my first post, I argued that SGPs are simply not designed to make inferences about teacher effectiveness. TheContinue reading “Piloting the Plane on Musical Instruments & using SGPs to Evaluate Teachers”

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 IContinue reading “Inkblots and Opportunity Costs: Pondering the Usefulness of VAM and SGP Ratings”

More on the SGP debate: A reply

This new post from Ed News Colorado is in response to my critique of Student Growth Percentiles here: https://schoolfinance101.wordpress.com/2011/09/02/take-your-sgp-and-vamit-damn-it/ I must say that I agree with almost everything in this response to my post, except for a few points. First, they argue: Unfortunately Professor Baker conflates the data (i.e. the measure) with the use. AContinue reading “More on the SGP debate: A reply”