Graphics Reference
In-Depth Information
Figure
.
.
Manual controls used to examine the sensitivity of the clustering revealed by the LDA
index to PC
and PC
is explored. Top let to top right plots: coe
cient on PC
reduced from
.
to
.
gives a smaller gap between clusters, but the clusters are still separable. Bottom let to bottom
right: coe
cient for PC
reduced from
.
to
.
which removes the cluster structure
But the right cluster is still separated. his suggests that PC
is important for sepa-
rating the two letmost clusters but not important for separating the right cluster.
Precomputed Choices
One of the simplest choices of target planes that creates a smooth transition from
scatterplot matrices is the little tour (McDonald,
) that interpolates between the
frames of a scatterplot matrix of all pairwise marginal projections. Conway et al.
(
) proposes a method for choosing a fixed number of target planes that are ap-
proximatelyequispaced. Itchoosesthe target planes using packing methodsonpoly-
topes and determines a shortest (Hamiltonian) path through the set of targets. Nei-
ther of these methods is implemented in GGobi.