ci.surface: Conditional Inference of Response Surface
In siRSM: Single-Index Response Surface Models

Computes 95% bootstrap confidence intervals for various features of the quadratic response surface, CONDITIONAL on the single index.

1	ci.surface(obj, B=500, use.parallel=TRUE)

`obj`	an object of class `siRSM`, typically result from `siRSM`
`B`	number of bootstrap samples
`use.parallel`	if TRUE, exploits multiple cores by using foreach, doSNOW, etc

In all components below, the lower 2.5% and upper 97.5% confidence limits, the mean, and the standard error are given:

`stationary.point`	stationary point, (`u0, v0`)
`prin.ax.1`	1st principal axis, intercept (`p10`) and slope (`p11`)
`prin.ax.2`	2nd principal axis, intercept (`p20`) and slope (`p21`)
`beta`	coefficients defining the quadratic response surface, `b0, b1, ..., b5`
`line.congr`	slope (`ax`) and curvature (`ax2`) along the congruence line, `u-v=0`
`line.incongr`	slope (`ax`) and curvature (`ax2`) along the congruence line, `u+v=0`