Estimating growth charts via nonparametric quantile regression: a practical framework with application in ecology
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We discuss a practical and effective framework to estimate reference growth charts via regression quantiles. Inequality constraints are used to ensure both monotonicity and non-crossing of the estimated quantile curves and penalized splines are employed to model the nonlinear growth patterns with respect to age. A companion R package is presented and relevant code discussed to favour spreading and application of the proposed methods.
KeywordsGrowth charts Nonparametric regression quantiles Penalized splines P. oceanica modelling R software
The authors would like to thank the referee for his/her valuable comments.
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