R: Plot smooth functions of a generalized additive model object.

plot.gamlps {blapsr}

R Documentation

Plot smooth functions of a generalized additive model object.

Description

Displays a plot of the fitted additive smooth components of an gamlps object. The routine can also be used to print a table of point and set estimates of an additive smooth term for a user-specified grid of values.

Usage

## S3 method for class 'gamlps'
plot(x, xp, smoo.index, cred.int = 0.95, plot.cred = TRUE,
     np = 100, fit.col = "blue", shade.col = "gray75", show.plot = TRUE,
     show.info = TRUE, ...)

Arguments

`x`	An object of class `gamlps`.
`xp`	A numeric vector of grid values on which to compute a point estimate and pointwise credible interval for the smooth function specified in `smoo.index`. The components of `xp` must be within the range of the observed covariate values for the corresponding smooth function. Results will be displayed in a table.
`smoo.index`	The index of the smooth function. For instance `smoo.index = 2` refers to the second smooth function specified in the `formula` of the `amlps` routine.
`cred.int`	The level of the pointwise credible interval to be computed for the smooth additive term. Default is `0.95`.
`plot.cred`	Logical. Should the credible intervals be plotted? Default is `TRUE`.
`np`	The number of points used to construct the plot of the smooth additive function. Default is 100 and allowed values are between 20 and 200.
`fit.col`	The color of the fitted curve.
`shade.col`	The shading color for the credible intervals.
`show.plot`	Logical. Should the plot be displayed? Default is `TRUE`.
`show.info`	Logical. Should the table of point and set estimates of the smooth function on the specified `xp` values be displayed? Default is `TRUE`.
`...`	Further arguments to be passed to `plot`.

Details

Produces a plot of a smooth additive term fitted with the gamlps function. On the y-axis, the estimated effective dimension of the smooth term is also displayed. At the bottom of each plot, vertical ticks indicate the location of the covariate values. The labels on the x-axis correspond to the covariate name associated to the smooth term.

Value

If xp is unspecified (the default), the routine will only return a plot of the estimated smooth curve. Otherwise, it provides a list with the following components:

`xp`	The chosen points on which to compute the smooth fit.
`sm.xp`	The estimated smooth fit at points specified in `xp`.
`sm.low`	The lower bound of the pointwise credible interval for the smooth additive function at points specified in `xp`.
`sm.up`	The upper bound of the pointwise credible interval for the smooth additive function at points specified in `xp`.
`cred.int`	The chosen level to compute credible intervals.
`smoo.index`	The index of the smooth function.

Author(s)

Oswaldo Gressani oswaldo_gressani@hotmail.fr.