Provide diagnostic plots to check model assumptions for fitted model
of class unitquantreg
.
Usage
# S3 method for unitquantreg
plot(
x,
which = 1L:4L,
caption = c("Residuals vs. indices of obs.", "Residuals vs. linear predictor",
"Working response vs. linear predictor", "Half-normal plot of residuals"),
sub.caption = paste(deparse(x$call), collapse = "\n"),
main = "",
ask = prod(par("mfcol")) < length(which) && dev.interactive(),
...,
add.smooth = getOption("add.smooth"),
type = "quantile",
nsim = 99L,
level = 0.95
)
Arguments
- x
fitted model object of class
unitquantreg
.- which
integer. if a subset of the plots is required, specify a subset of the numbers 1 to 4, see below for further details.
- caption
character. Captions to appear above the plots.
- sub.caption
character. Common title-above figures if there are multiple.
- main
character. Title to each plot in addition to the above caption.
- ask
logical. If
TRUE
, the user is asked before each plot.- ...
other parameters to be passed through to plotting functions.
- add.smooth
logical. Indicates if a smoother should be added to most plots
- type
character. Indicates type of residual to be used, see
residuals.unitquantreg
.- nsim
integer. Number of simulations in half-normal plots, see
hnp.unitquantreg
.- level
numeric. Confidence level of the simulated envelope, see
hnp.unitquantreg
.
Details
The plot
method for unitquantreg
objects produces four types
of diagnostic plot.
The which
argument can be used to select a subset of currently four
supported plot, which are: Residuals versus indices of observations
(which = 1
); Residuals versus linear predictor (which = 2
);
Working response versus linear predictor (which = 3
) to
check possible misspecification of link function; Half-normal plot of
residuals (which = 4
) to check distribution assumption.
References
Dunn, P. K. and Smyth, G. K. (2018) Generalized Linear Models With Examples in R, Springer, New York.