# plot.frfast: Visualization of 'frfast' objects with the base graphics In npregfast: Nonparametric Estimation of Regression Models with Factor-by-Curve Interactions

## Description

Useful for drawing the estimated regression function, first and second derivative (for each factor's level). Additionally, with the `diffwith` argument it is possible to draw the differences between two factor's levels.

## Usage

 ```1 2 3 4 5 6 7``` ```## S3 method for class 'frfast' plot(x = model, y, fac = NULL, der = NULL, diffwith = NULL, points = TRUE, xlab = model\$name[2], ylab = model\$name[1], ylim = NULL, main = NULL, col = "black", CIcol = "black", pcol = "grey80", ablinecol = "red", abline = TRUE, type = "l", CItype = "l", lwd = 2, CIlwd = 1, lty = 1, CIlty = 2, cex = 0.6, ...) ```

## Arguments

 `x` `frfast` object. `y` NULL. `fac` Vector which determines the level to take into account in the plot. By default is `NULL`. `der` Number or vector which determines any inference process. By default `der` is `NULL`. If this term is `0`, the plot shows the initial estimate. If it is `1` or `2`, it is designed for the first or second derivative, respectively. `diffwith` Factor's level used for drawing the differences respect to the level specified in the `fac` argument. By default, `NULL`. The differences are computed for the r-th derivative speciefied in the `der` argument. `points` Draw the original data into the plot. By default it is `TRUE`. `xlab` A title for the `x` axis. `ylab` A title for the `y` axis. `ylim` The `y` limits of the plot. `main` An overall title for the plot. `col` A specification for the default plotting color. `CIcol` A specification for the default confidence intervals plotting color. `pcol` A specification for the points color. `ablinecol` The color to be used for `abline`. `abline` Draw an horizontal line into the plot of the second derivative of the model. `type` What type of plot should be drawn. Possible types are, `p` for points, `l` for lines, `o` for overplotted, etc. See details in `par`. `CItype` What type of plot should be drawn for confidence intervals. Possible types are, `p` for points, `l` for lines, `o` for overplotted. `lwd` The line width, a positive number, defaulting to 1. See details in `par`. `CIlwd` The line width for confidence intervals, a positive number, defaulting to 1. `lty` The line type. Line types can either be specified as an integer (0 = blank, 1 = solid (default), 2 = dashed, 3 = dotted, 4 = dotdash, 5 = longdash, 6 = twodash). See details in `par`. `CIlty` The line type for confidence intervals. Line types can either be specified as an integer (0 = blank, 1 = solid (default), 2 = dashed, 3 = dotted, 4 = dotdash, 5 = longdash, 6 = twodash). `cex` A numerical value giving the amount by which plotting symbols should be magnified relative to the default. See details in `par`. `...` Other options.

## Value

Simply produce a plot.

## Author(s)

Marta Sestelo, Nora M. Villanueva and Javier Roca-Pardinas.

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20``` ```library(npregfast) data(barnacle) # Nonparametric regression without interactions fit <- frfast(DW ~ RC, data = barnacle, nboot = 100) plot(fit) plot(fit, der = 0) plot(fit, der = 0, points = FALSE) plot(fit, der = 1, col = "red", CIcol = "blue") # Nonparametric regression with interactions fit2 <- frfast(DW ~ RC : F, data = barnacle, nboot = 100) plot(fit2) plot(fit2, der = 0, fac = "lens") plot(fit2, der = 1, col = "grey", CIcol = "red") plot(fit2, der = c(0,1), fac = c("barca","lens")) # Visualization of the differences between two factor's levels plot(fit2, fac = "barca", diffwith = "lens") plot(fit2, fac = "barca", diffwith = "lens", der = 1) ```

npregfast documentation built on May 29, 2017, 12:29 p.m.