“Heterogeneity of variance in experimental studies: A challenge to conventional interpretations”

Statistical Modeling, Causal Inference, and Social Science 2013-06-09

Summary:

Avi sent along this old paper from Bryk and Raudenbush, who write: The presence of heterogeneity of variance across groups indicates that the standard statistical model for treatment effects no longer applies. Specifically, the assumption that treatments add a constant to each subject’s development fails. An alternative model is required to represent how treatment effects [...]

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Link:

http://andrewgelman.com/2013/06/09/heterogeneity-of-variance-in-experimental-studies-a-challenge-to-conventional-interpretations/

From feeds:

Statistics and Visualization » Statistical Modeling, Causal Inference, and Social Science

Tags:

multilevel modeling causal inference

Authors:

Andrew

Date tagged:

06/09/2013, 13:40

Date published:

06/09/2013, 09:40