RSA (version 0.5.1)

demoRSA: Plots a response surface of a polynomial equation of second degree with interactive controls

Description

Plots an RSA object, or a response surface with specified parameters, with interactive controls for coefficients.

Usage

demoRSA(x = NULL, y = 0, x2 = 0, y2 = 0, xy = 0, w = 0,
    wx = 0, wy = 0, b0 = 0, type = "3d", zlim = c(-2, 2),
    xlim = c(-2, 2), ylim = c(-2, 2), points = FALSE,
    model = "full", extended = FALSE, ...)

Arguments

x

Either an RSA object (returned by the RSA function), or the coefficient for the X predictor

y

Y coefficient

x2

X^2 coefficient

y2

Y^2 coefficient

xy

XY interaction coefficient

w

W coefficient (for (un)constrained absolute difference model)

wx

WX coefficient (for (un)constrained absolute difference model)

wy

WY coefficient (for (un)constrained absolute difference model)

b0

Intercept

xlim

Limits of the x axis

ylim

Limits of the y axis

zlim

Limits of the z axis

type

3d for 3d surface plot, contour for 2d contour plot. Shortcuts (i.e., first letter of string) are sufficient; be careful: "contour" is very slow at the moment

points

Should the original data points be overplotted?

model

If x is an RSA object: from which model should the response surface be computed?

extended

Show additional controls (not implemented yet)

...

Other parameters passed through to plot.RSA (e.g., xlab, ylab, zlab, cex, legend)

Details

No details so far. Just play around with the interface!

See Also

plotRSA, RSA

Examples

# Plot response surfaces from known parameters
# example of Edwards (2002), Figure 3
demoRSA(x=.314, y=-.118, x2=-.145, y2=-.102, xy=.299, b0=5.628, type="3d")
demoRSA(x=.314, y=-.118, x2=-.145, y2=-.102, xy=.299, b0=5.628, legend=FALSE, type="c")

# Plot response surface from an RSA object
set.seed(0xBEEF)
n <- 300
err <- 2
x <- rnorm(n, 0, 5)
y <- rnorm(n, 0, 5)
df <- data.frame(x, y)
df <- within(df, {
	diff <- x-y
	absdiff <- abs(x-y)
	sqdiff <- (x-y)^2
	z.diff <- diff + rnorm(n, 0, err)
	z.abs <- absdiff + rnorm(n, 0, err)
	z.sq <- sqdiff + rnorm(n, 0, err)
	z.add <- diff + 0.4*x + rnorm(n, 0, err)
	z.complex <- 0.4*x + - 0.2*x*y + + 0.1*x^2 - 0.03*y^2 + rnorm(n, 0, err)
})

r1 <- RSA(z.sq~x*y, df)
demoRSA(r1)
demoRSA(r1, points=TRUE, model="sqdiff")