Abstract
In this article, regression splines are used inside linear mixed models to explore nonlinear longitudinal data. The regression spline bases are generated using a single knot chosen using biological information—a knot position supported by an automated knot selection procedure. A variety of inferential procedures are compared. The variance in the data was closely modeled using a flexible model-based covariance structure, a robust method and the nonparametric bootstrap, while the variance was underestimated when independent random effects were assumed.
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Mackenzie, M.L., Donovan, C.R. & McArdle, B.H. Regression spline mixed models: A forestry example. JABES 10, 394 (2005). https://doi.org/10.1198/108571105X80194
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DOI: https://doi.org/10.1198/108571105X80194