This R tutorial describes how to create an ECDF plot (or Empirical Cumulative Density Function) using R software and ggplot2 package. ECDF reports for any given number the percent of individuals that are below that threshold.
The function stat_ecdf() can be used.
Create some data
set.seed(1234)
df <- data.frame(height = round(rnorm(200, mean=60, sd=15)))
head(df)## height
## 1 42
## 2 64
## 3 76
## 4 25
## 5 66
## 6 68ECDF plots
library(ggplot2)
ggplot(df, aes(height)) + stat_ecdf(geom = "point")
ggplot(df, aes(height)) + stat_ecdf(geom = "step")
For any value, say, height = 50, you can see that about 25% of our individuals are shorter than 50 inches
Customized ECDF plots
# Basic ECDF plot
ggplot(df, aes(height)) + stat_ecdf(geom = "step")+
labs(title="Empirical Cumulative \n Density Function",
y = "F(height)", x="Height in inch")+
theme_classic()
Infos
This analysis has been performed using R software (ver. 3.2.4) and ggplot2 (ver. 2.1.0)