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Graphical methods

The function call plot(i1) returns a scatterplot matrix of the response and the principal directions. The call plot(i1,mark.by.y=TRUE) produces a scatterplot matrix of the principal directions, but with points marked (colored) according to the value of the response; the point marking does not work with Splus. The function call dr.coplot(i1) returns a plot of the response versus the first principal direction, with a separate panel conditioning on the value of the second principal direction (a coplot). The call dr.coplot(i1,mark.by.y=T), gives a coplot of the first direction versus the second direction conditioning on the third direction and using color to encode the information about the response. The function rotplot is a generic function that allows looking at a number of static views of a 3D plot. The call
> rotplot(dr.directions(m1,1:2),dr.y(m1),number=16)
gives 16 views of the 3D plot of the response versus linear combinations of the first two principal directions.

Sandy Weisberg 2002-01-10