surface.stats: Statistics of Quadratic Response Surface

In siRSM: Single-Index Response Surface Models

Description

Computes stationary point, 1st and 2nd principal axes of the quadratic response surface, shapes and curvatures along the congruence and incongruence lines, as well as various parameters useful for plot.siRSM.

Usage

surface.stats(obj)
surface.stats.main(b, xlim, ylim)

Arguments

obj	an object of class siRSM, often the result of siRSM
b	coefficients of the response surface, e.g., obj$coef where obj is an object of class siRSM
xlim	x-boundaries in 3D (x,y,z)-perspective plot — used when surface.stats.main is called internally by plot.siRSM
ylim	y-boundaries in 3D (x,y,z)-perspective plot — used when surface.stats.main is called internally by plot.siRSM

Value

u0	x-coordinates of surface's stationary point
v0	y-coordinates of surface's stationary point
p10	intercept in xy-plane of surface's 1st principal axis
p11	slope in xy-plane of surface's 1st principal axis
p20	intercept in xy-plane of surface's 2nd principal axis
p21	slope in xy-plane of surface's 2nd principal axis
ax.congr	slope of surface along the congruence line, u-v=0
ax2.congr	curvature of surface along the congruence line, u-v=0
ax.incongr	slope of surface along the incongruence line, u+v=0
ax2.incongr	curvature of surface along the incongruence line, u+v=0
pl	intersection of 1st axis at lower border, to be used by plot.siRSM
ph	intersection of 1st axis at upper border, to be used by plot.siRSM
sl	intersection of 2nd axis at lower border, to be used by plot.siRSM
sh	intersection of 2nd axis at upper border, to be used by plot.siRSM

Author(s)

Huan Cheng, Mu Zhu

References

Edwards JR (2002), "Alternatives to difference scores: Polynomial regression analysis and response surface methodology," in Measuring and Analyzing Behavior in Organizations: Advances in Measurement and Data Analysis (F. Drasgow, N. Schmitt, Eds.), Jossey-Bass, pp. 350-400.

siRSM documentation built on May 29, 2017, 10:54 a.m.