ggdensity: Improved Bivariate Density Visualization in R

Baylor University

jamesotto852@gmail.com

Baylor University

david_kahle@baylor.edu

Abstract

The ggdensity R package extends the functionality of ggplot2 by providing more interpretable visualizations of bivariate density estimates using highest density regions (HDRs). The visualizations are created via drop-in replacements for the standard ggplot2 functions used for this purpose: geom_hdr() for geom_density_2d_filled() and geom_hdr_lines() for geom_density_2d(). These new geoms improve on those of ggplot2 by communicating the probabilities associated with the displayed regions. Various statistically rigorous estimators are available, as well as convenience functions geom_hdr_fun() and geom_hdr_fun_lines() for plotting HDRs of user-specified probability density functions. Associated geoms for rug plots and pointdensity scatterplots are also presented.

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