cplot: Consistency plot for Key Comparisons
In metRology: Support for Metrological Applications

Description Usage Arguments Details Value Author(s) See Also Examples

Produces a consistency plot for typical metrology comparison data.

  cplot(x,u,labels=names(x), p.adjust.method="holm", ordered=TRUE,
        breaks=c(0,0.001,0.01, 0.05, 0.1,1), 
        col=terrain.colors(length(breaks)-1), log.p=FALSE,
        main=paste("Consistency map -", deparse(substitute(x))), 
        subtitle=NULL, key=FALSE, 
        key.width=2.54, key.height=0.6,...)

`x`	Vector of reported values
`u`	Vector of length `length(x)` of standard uncertainties
`labels`	Vector of of length `length(x)` labels for x-axis marks.
`p.adjust.method`	p-value adjustment method; passed to `p.adjust`.
`ordered`	If `TRUE` (the default) observations are arranged in ascending order of `x`.
`breaks`	Vector of breaks; passed to `image`.
`col`	Vector of colours of length `length(breaks)-1`. Passed to `image`.
`log.p`	If `TRUE`, the plot shows `-log_10(p)`.
`main, subtitle`	Main and subtitle for plot.
`key`	If `TRUE` a key is added to the plot.
`key.width, key.height`	Width and height of key, if plotted. See details for specification.
`...`	Graphical parameters passed to `image`. If present, `cex.axis` is passed to `axis` for main figure axes only.

Calculates the (square, symmetric matrix of) optionally adjusted p-values for a two-tailed z-test of |x[i]-x[j]|/sqrt(u[i]^2+u[j]^2) against zero and plots the p-values as an image.

p.adjust is called prior to plotting to correct for multiple comparisons. To suppress adjustment, set p.adjust.method="none".

key.height is a fraction of the figure region height. key.width is the width of the key area in cm, unless under 1, in which case it is interpreted as a fraction of the plot region width.

If log.p is TRUE and subtitle NULL, a subtitle indicating the use of log.p is added to the plot,

Invisibly returns a matrix of pairwise test p-values or, if log.p==TRUE, matrix of -log_10(p).

S Ellison s.ellison@lgc.co.uk

p.adjust, image.