plotdeplot.lmscreg: Density Plot for LMS Quantile Regression In VGAM: Vector Generalized Linear and Additive Models

Description

Plots a probability density function associated with a LMS quantile regression.

Usage

 ```1 2 3 4``` ```plotdeplot.lmscreg(answer, y.arg, add.arg = FALSE, xlab = "", ylab = "density", xlim = NULL, ylim = NULL, llty.arg = par()\$lty, col.arg = par()\$col, llwd.arg = par()\$lwd, ...) ```

Arguments

 `answer` Output from functions of the form `deplot.???` where `???` is the name of the VGAM LMS family function, e.g., `lms.yjn`. See below for details. `y.arg` Numerical vector. The values of the response variable at which to evaluate the density. This should be a grid that is fine enough to ensure the plotted curves are smooth. `add.arg` Logical. Add the density to an existing plot? `xlab, ylab` Caption for the x- and y-axes. See `par`. `xlim, ylim` Limits of the x- and y-axes. See `par`. `llty.arg` Line type. See the `lty` argument of `par`. `col.arg` Line color. See the `col` argument of `par`. `llwd.arg` Line width. See the `lwd` argument of `par`. `...` Arguments passed into the `plot` function when setting up the entire plot. Useful arguments here include `main` and `las`.

Details

The above graphical parameters offer some flexibility when plotting the quantiles.

Value

The list `answer`, which has components

 `newdata` The argument `newdata` above from the argument list of `deplot.lmscreg`, or a one-row data frame constructed out of the `x0` argument. `y` The argument `y.arg` above. `density` Vector of the density function values evaluated at `y.arg`.

Note

While the graphical arguments of this function are useful to the user, this function should not be called directly.

Thomas W. Yee

References

Yee, T. W. (2004). Quantile regression via vector generalized additive models. Statistics in Medicine, 23, 2295–2315.

`deplot.lmscreg`.
 ``` 1 2 3 4 5 6 7 8 9 10 11 12``` ```fit <- vgam(BMI ~ s(age, df = c(4,2)), lms.bcn(zero = 1), bmi.nz) ## Not run: y = seq(15, 43, by = 0.25) deplot(fit, x0 = 20, y = y, xlab = "BMI", col = "green", llwd = 2, main = "BMI distribution at ages 20 (green), 40 (blue), 60 (orange)") deplot(fit, x0 = 40, y = y, add = TRUE, col = "blue", llwd = 2) deplot(fit, x0 = 60, y = y, add = TRUE, col = "orange", llwd = 2) -> aa names(aa@post\$deplot) aa@post\$deplot\$newdata head(aa@post\$deplot\$y) head(aa@post\$deplot\$density) ## End(Not run) ```