Fixed and random effects models: making an informed choice

This paper assesses the options available to researchers analysing multilevel (including longitudinal) data, with the aim of supporting good methodological decision-making. Given the confusion in the literature about the key properties of fixed and random effects (FE and RE) models, we present these models’ capabilities and limitations. We also discuss the within-between RE model, sometimes misleadingly labelled a ‘hybrid’ model, showing that it is the most general of the three, with all the strengths of the other two. As such, and because it allows for important extensions—notably random slopes—we argue it should be used (as a starting point at least) in all multilevel analyses. We develop the argument through simulations, evaluating how these models cope with some likely mis-specifications. These simulations reveal that (1) failing to include random slopes can generate anti-conservative standard errors, and (2) assuming random intercepts are Normally distributed, when they are not, introduces only modest biases. These results strengthen the case for the use of, and need for, these models

Juggling multiple accountability systems: how three principals manage these tensions in Ontario, Canada

Accountability in education is not new. Schools have always been accountable in one way or another to the communities they serve, regardless of the policy environment of the time (Elmore, The Educational Forum, 69:134–142, 2005). This article explores how three principals from Ontario, Canada manage the tensions of multiple accountability systems in their work. Findings indicate that the principals were able to find ways to be accountable to a variety of communities and ideals by prioritizing and honoring local needs and beliefs within the larger provincial mandate. Principals could not ignore the various accountability pressures; indeed, their success hinged on the ability to negotiate them. This delicate balancing act requires school principals to develop skills necessary to successfully juggle these competing demands