Analytical Package for Education Trials


eefAnalytics provides both frequentist and Bayesian multilevel models for analyzing education trials. Multilevel model or random effect model is an "omnibus" model that can be used to analyse multi-site trials, cluster randomised controlled trials and simple randomised trials across schools. The model reduces to ordinary linear regression when intra-cluster correlation is zero and number of pupils is the same in each school . The frequentist method relies on lme4 package and the implementation of Hedges'effect size based on unequal cluster size for 'within' and 'total' variance (Hedges, 2007). The Bayesian method relies on the packages geoR for scaled-inverse-Chi-square and mvtnorm for multivariate Normal distribution. The estimation are based on Gibb's sampling from the full conditional posterior distributions as discussed by Wang et al. (1993). To guarantee convergence of the mcmc chains, a minimum of 10,000 iterations is recommended. All parameters are based on vague priors and in most cases the results should be similar to the frequentist method.


Adetayo Kasim

ZhiMin Xiao

Steve Higgins


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Weinberger, M., Oddone, E., Henderson, W., Smith, D., Huey, J., Giobbie-Hurder, A., & Feussner, J. (2001). Multisite Randomized Controlled Trials in Health Services Research: Scientific Challenges and Operational Issues. Medical Care, 39 (6), 627-634.

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