Validating Growth Models CCSSO National Conference on Student

Validating Growth Models CCSSO National Conference on Student Assessment June 30, 2017

Validity and Validation • In olden days, validity and validation were not quite so complicated…

So let it be written. So let it be done.

Why is your use of those test scores valid?

Validating the Growth Model • … a process to ensure the growth model is valid for its intended purpose • What is the intended purpose? – Of the accountability system? • Of the growth model within the accountability system?

Why Growth? • Someone needs to be able to explain the role of growth within the accountability system? – Not only to help determine whether the appropriate growth model has been selected? – But also to help with the evaluation of whether it is serving its intended purpose as we validate the accountability system • Validating the Accountability System – Braun (2008) Vicissitudes of the Validators

Validity of Accountability Systems • Braun’s (2008) argument regarding the validity of accountability systems: 1. An accountability system is imposed or implemented with the intent that it will accomplish its desired goals (e. g. , increased student achievement). 2. The mechanism by which this will happen is called the “theory-of-action”. 3. In validating an accountability system, theory-ofaction plays the same role as does the construct in test validation. 4. Thus, consequential validity is the ultimate criterion by which we should judge an accountability system.

“Theory of Action” • The accountability system – Results in classifications – Identifies schools for support and assistance – Leads to actions – Actions lead to improvement • How does growth fit into the model? – What are the intended uses and interpretations of growth as part of the model? – Is there a clear path for that information to lead to the desired actions?

Back to Braun 4. consequential validity is the ultimate criterion by which we should judge an accountability system. • Ultimate consequential validity question– Did the implementation of the accountability system lead to the desired improvements in performance? • There are lots of dots to connect between the design of the accountability system and improved student performance. • As with everything else, trained professionals and fidelity of implementation are critical. • Isolating and evaluating the role and impact of the growth model could be difficult? • Is it necessary or useful to do so? • How does validating the growth model fit into the overall plan for validating the accountability system?