Stress plot for parametric survival distributions.

DESCRIPTION:

Plot quantiles for covariate value versus time to failure for parametric failure time models.

USAGE:

stressplot.censorReg(object, p = c(0.01, 0.05, 0.1, 0.5), method="KM", 
     main.title=<<see below>>, sub=<<see below>>,
     xlab="Time to Failure", ylab=NULL, units=NULL, add=F,
     lty=1:length(p), col=1 + 1:length(p), xlim=NULL, ylim=NULL,
     add.data=T, jitter.data=F, add.legend=F, legend.loc=NULL)

REQUIRED ARGUMENTS:

object
an object of class "censorReg" or of class "censorRegList" with exactly one independent or stratification variable (offset variables are okay).

OPTIONAL ARGUMENTS:

p
a vector of probabilities for which quantiles are to be computed. The quantiles at each covariate value are plotted. Quantiles with the same probability are connected with a line.
method
in addition to quantiles for the model used to compute object, quantiles for one further model can be plotted as points. Let the covariate be "x", and let the response be "censor(y)". Then the possible methods for these alternative models are: "KM" censor(y) ~ strata(x) Turnbull's generalization of Kaplan-Meier estimates "separate" censor(y) ~ strata(x) censorReg estimates with separate location and scale for each covariate value. "factor" censor(y) ~ factor(x) censorReg estimates with separate location and the same scale for each covariate value "regression" censor(y) ~ x censorReg model with location predicted by regression on the covariate "none" The comparison points are not plotted. The default is method="KM".
main.title
a character string specifying the main title for the plot. The default is paste("S/N Plot for ", deparse(substitute(object)), "\n", "method = ", method2, "(", method, "), ", distribution2, "(", link2, ")", sep = "")
sub
a character string specifying the sub-title for the plot. The default is attr(object, "date").
xlab
a character string specifying the x-axis label.
ylab
a character string specifying the y-axis label.
units
a character string specifying units label for the x-axis label.
lty
numeric vector of line types. Each group defined by argument p results in a different line and marker type. Argument lty specifies the line types (see par).
col
numeric vector of color types. Each group defined by argument p results in a different color type. Argument col specifies the color types (see par).
xlim
the x-axis limits (see par).
ylim
the y-axis limits (see par).
add.data
if TRUE, data are displayed on the plot.
jitter.data
if TRUE, jittered data are displayed on the plot.
add.legend
if TRUE, a legend is added to the plot (using the locator function) giving the quantiles associated with each line and color type.
legend.loc
"x" and "y" plotting points for the upper left corner of legend. if NULL and add.legend=T, the locator function is used so you must click in the graph at the point for locating the upper left corner of the legend. An option is legend.loc="auto" which automatically locates the legend.

SIDE EFFECTS:

A plot of the covariate versus the time to failure at the indicated quantiles is displayed.

SEE ALSO:

EXAMPLES:

a <- censorReg(censor(days,event)~voltage, data=capacitor2, weights=weights)
stressplot.censorReg(a, method="separate")
stressplot.censorReg(a)