NADA2 (version 1.1.8)

ATSmini: Kendall's tau and ATS line for censored data

Description

Computes Kendall's tau and the Akritas-Theil-Sen (ATS) line for censored data. Is called by censeaken because it is much faster than the ATS function. It is not expected to be of much use to users on its own. The x variable (time) may not be censored.

Usage

ATSmini(y.var, y.cen, x.var)

Value

Returns the intercept and slope (ATS line), tau (Kendall's tau), p-value and S-value (test statistic).

Arguments

y.var

The column of y (response variable) values plus detection limits.

y.cen

The y-variable 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.

x.var

The column of x (time for a trend test) values.

References

Akritas, M.G., Murphy, S.A., LaValley, M.P., 1995. The Theil-Sen Estimator With Doubly Censored Data and Applications to Astronomy. Journal of the American Statistical Association 90, 170–177. https://doi.org/10.2307/2291140

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

See Also

NADA::cenken

Examples

# x may not be censored.  Use the ATS function when x is censored.
data(Brumbaugh)

with(Brumbaugh, ATSmini(Hg, HgCen, SedLOI))