NADA2 (version 1.1.8)

ordranks: Computes ranks of data with one or multiple detection limits

Description

Computes the within-column ranks of data having one or more detection limits. If multiple limits are present in a column, data are first re-censored at the highest detection limit.

Usage

ordranks(dat.frame, paired = TRUE)

Value

Returns columns of ranks of censored data in the same order as the paired columns of input data. For 3 chemical parameters, the data frame returned will be R1 R2 R3 where R represents the ranks of the C1 C2 C3 input data accounting for the censoring indicated by columns I1 I2 I3.

Arguments

dat.frame

A data frame. Default format is paired = TRUE, where for 3 chemical parameters the input format is C1 I1 C2 I2 C3 I3, a concentration column followed by its censoring indicator column.

paired

An option to specify paired = FALSE, where the input format would be C1 C2 C3 I1 I2 I3 where the C columns contain concentrations or a detection limit, and the I columns are their associated indicators, in the same order as the concentration columns.

References

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

Examples

library(NADA) #For example data
data(PbHeron)

ordranks(PbHeron[,4:15])