Graphics Reference
In-Depth Information
Figure . . Points identified by regression diagnostics in Fig. . (File: hh/csc/code/kidney .s)
Analysis of Covariance Plots
6.5
Analysis of covariance (ANCOVA) plots are defined by the Cartesian product of dis-
play format. In Fig. . , an example with one factor and one covariate, we show sep-
arate panels for each level of the factor on the let side and superposed panels on
the right side. he display extends naturally to ANCOVA with two factors and one
covariate.
. he ancova function constructs both theANOVAtable andtheANCOVAplot
from a single specification of a model formula.
. Depending on the level of overlap of the x-andy-ranges and the collinearity of
the groups, it may be more advantageous to look at the set of separate panels or
atthesinglesuperposedpanel.Wedisplayboth.
Search WWH ::




Custom Search