cenCompareCdfs: Comparison of empirical cdf of censored data

In NADA2: Data Analysis for Censored Environmental Data

Comparison of empirical cdf of censored data

Description

Plots the empirical cdf and cdfs of three theoretical distributions, fit by maximum likelihood estimation (MLE).

Usage

cenCompareCdfs(x.var, cens.var, dist3 = "norm", Yname = yname)

Arguments

x.var	The column of y (response variable) values plus detection limits
cens.var	The column of indicators, where 1 (or TRUE) indicates a detection limit in the y.var column, and 0 (or FALSE) indicates a detected value in y.var.
dist3	Name of the third distribution to be plotted, default is norm (normal distribution). Alternate third distribution is weibull(for Weibull distribution). Log-normal and gamma distributions are always used.
Yname	Optional – input text in quotes to be used as the variable name. The default is the name of the y.var input variable.

Value

prints a plot of the empirical CDFs with BIC value for each distribution.

References

Helsel, D.R., 2011. Statistics for Censored Environmental Data using Minitab and R, 2nd ed. John Wiley & Sons, USA, N.J.

Delignette-Muller, M., Dutang, C., 2015. fitdistrplus : An R Package for Fitting Distributions. Journal of Statistical Software, 64, 1-34. http://www.jstatsoft.org/v64/i04/.

Examples

data(Brumbaugh)
cenCompareCdfs(Brumbaugh$Hg,Brumbaugh$HgCen)

# With Weibull distribution
cenCompareCdfs(Brumbaugh$Hg,Brumbaugh$HgCen,dist3="weibull")

# Using an distribution not supported by this function (yet)
# you will get an error message
## Not run: cenCompareCdfs(Brumbaugh$Hg,Brumbaugh$HgCen,dist3="beta")

# With Yname specified
cenCompareCdfs(Brumbaugh$Hg,Brumbaugh$HgCen,Yname="TCE Conc (ug/L)\nLong Island, NY USA")

NADA2 documentation built on Oct. 20, 2023, 5:07 p.m.