FlexParamCurve: R package for flexible fitting of nonlinear parametric curves
Article first published online: 10 AUG 2012
© 2012 The Authors. Methods in Ecology and Evolution © 2012 British Ecological Society
Methods in Ecology and Evolution
Volume 3, Issue 6, pages 1073–1077, December 2012
How to Cite
Oswald, S. A., Nisbet, I. C. T., Chiaradia, A. and Arnold, J. M. (2012), FlexParamCurve: R package for flexible fitting of nonlinear parametric curves. Methods in Ecology and Evolution, 3: 1073–1077. doi: 10.1111/j.2041-210X.2012.00231.x
- Issue published online: 11 DEC 2012
- Article first published online: 10 AUG 2012
- Received 30 December 2011; accepted 15 May 2012 Handling Editor: Mark Rees
- growth analysis;
- nonmonotonic curve;
- nonlinear mixed-effects models;
- nlsList() ;
- parametric curve-fitting
1. Nonlinear, parametric curve-fitting provides a framework for understanding diverse ecological and evolutionary trends (e.g. growth patterns and seasonal cycles). Currently, parametric curve-fitting requires a priori assumptions of curve trajectories, restricting their use for exploratory analyses. Furthermore, use of analytical techniques [nonlinear least-squares (NLS) and nonlinear mixed-effects models] for complex parametric curves requires efficient choice of starting parameters.
2. We illustrate the new R package FlexParamCurve that automates curve selection and provides tools to analyse nonmonotonic curve data in NLS and nonlinear mixed-effects models. Examples include empirical and simulated data sets for the growth of seabird chicks.
3. By automating curve selection and parameterization during curve-fitting, FlexParamCurve extends current possibilities for parametric analysis in ecological and evolutionary studies.