NADA2 (version 1.1.8)

cenCompareCdfs: 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)

Value

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

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.

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
if (FALSE) cenCompareCdfs(Brumbaugh$Hg,Brumbaugh$HgCen,dist3="beta")

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