Online Program

Saturday, February 22
CS23 Modeling Techniques Sat, Feb 22, 10:45 AM - 12:15 PM
Bayshore VI

Fractional Polynomials: Flexible, Interpretable, and an Alternative to Splines (302751)

*Michael D. Regier, West Virginia University, Department of Biostatistics 

Keywords: Fractional polynomials, splines, smoothing, interpretation, modern regression methods

Fractional polynomials is a powerful smoothing technique that has been implemented in statistical packages such as R and Stata. It has been applied to medical administrative data, force of infection in animal husbandry, and epidemiological exposure-response relationships. Research involving fractional polynomials continues to grow as there are many open questions concerning their properties and utility. In this presentation, we review fractional polynomials, their use, implementation, and interpretation. We demonstrate this regression technique with an ecological public health data set and a biomarker dose-response data set. For both sets of data, we will compare fractional polynomials with splines, emphasizing the differences between the approaches with respect to the modeling objectives. Finally, we will discuss the problem of model selection for fractional polynomials and compare current model-selection techniques.