cell: Calculate confidence ellipses for parameters in linear models...
In p3d: Plot 3d data and fitted surfaces

Description Usage Arguments Value Author(s) See Also Examples

cell is similar to confidence.ellipse in the car package, except that cell returns the points to form the ellipse(s) which must be plotted with plot(...,type='l') or lines(...). It currently has methods for lm (cell.default) and glh objects.

cell(object, ...)

## Default S3 method:
cell(object, which.coef, levels = 0.95, Scheffe = FALSE, dfn = 2, center.pch = 19, 
center.cex = 1.5, segments = 51, xlab, ylab, las = par("las"), col = palette()[2], lwd = 2, lty = 1, 
add = FALSE, ...)

## S3 method for class 'glh'
cell(object, which.coef = 1:2, levels = 0.95, Scheffe = FALSE, dfn = 2, center.pch = 19, 
center.cex = 1.5, segments = 51, xlab, ylab, las = par("las"), col = palette()[2], lwd = 2, 
lty = 1, add = FALSE, ...)

`object`	A `lm` or `glh` object
`which.coef`	Indices of the coefficients, from `coef(object)` for which the confidence ellipse is to be constructed.
`levels`	One or more values of the confidence coverage of the ellipse(s).
`Scheffe`	Whether to apply Scheffe correction for dimensionality of the hypothesis
`dfn`	The Scheffe dimension used to calculate the radii of the ellipse(s). i.e., use `dfn = 1` to generate ellipses whose shadows are ordinary confidence intervals for individual parameters; use `dfn = 2` for 2-dimensional ellipses, etc.
`center.pch`	Plotting character used to mark the center of the ellipse(s)
`center.cex`	Size of the plotting character
`segments`	Number of line segments used to generate the ellipse(s)
`xlab`	Label for the horizontal coefficient of the plot.
`ylab`	Label for the vertical coefficient of the plot.
`las`	Style of axis labels
`col`	Color for the ellipse(s)
`lwd`	Line width for the ellipse(s)
`lty`	Line type for the ellipse(s)
`add`	This argument is not presently used
`...`	Other arguments passed down [where?]