# Methods for Function plot

`plot-methods.Rd`

Methods for function `plot`

to produce different diagonostic plots for an object of class "MultiChainLadder".

## Usage

```
# S4 method for class 'MultiChainLadder,missing'
plot(x, y, which.plot=1:4,
which.triangle=NULL,
main=NULL,
portfolio=NULL,
lowess=TRUE,
legend.cex=0.75,...)
```

## Arguments

- x
An object of class "MultiChainLadder".

- y
"missing"

- which.plot
This specifies which type of plot is desired. Its range is 1:5, but defaults to 1:4. "1" is the barplot of observed losses and predicted IBNR stacked and MSE predictions as error bars; "2" is a trajectory plot of the development pattern; "3" is the residual plot of standardized residuals against the fitted values; "4" is the Normal-QQ plot of the standardized residuals. "5" is the "xyplot" of development with confidence intervals for each accident year. Note that "3" and "4" are not available for portfolio.

- which.triangle
This specifies which triangles are to be plotted. Default value is NULL, where all triangles plus the portfolio result will be plotted.

- main
It should be a list of titles for each plot. If not supplied, use default titles.

- portfolio
It specifies which triangles are to be summed as the portfolio, to be passed on to

`summary`

.- lowess
Logical. If

`TRUE`

, smoothing lines will be added on residual plots.- legend.cex
plotting parameter to be passes on to

`cex`

in`legend`

if`which.plot=1`

.- ...
optional graphical arguments.

## See also

See also `MultiChainLadder`

## Examples

```
if (FALSE) { # \dontrun{
data(liab)
fit.liab <- MultiChainLadder(liab)
# generate diagonostic plots
par(mfcol=(c(3,2)))
plot(fit.liab,which.plot=1:2)
par(mfrow=(c(2,2)))
plot(fit.liab,which.plot=3:4)
plot(fit.liab,which.triangle=1,which.plot=5)
graphics.off()
} # }
```