Effect sizes describe the magnitude of findings from statistical analyses. They provide a common metric and allow for easy comparison of findings across studies and across outcomes. Effect sizes are recognized standards that are not influenced by sample size, but the impact of measurement on estimated effect sizes is too often ignored. This paper describes why effect sizes are effected by measurement precision, briefly discusses measurement precision across age and developmental domain, and describes how different types of effect sizes are effected by measurement precision.
Publication Date: March 5, 2007
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