Graphics Reference
In-Depth Information
Figure
.
.
D dendrogram for the first two principal components
he first two principal component scores are plotted and the dendrogram is con-
structed according to the hierarchical clustering method. X
D graphics make it easy
to realize
D graphical representations via statistical sotware like R or XploRe.
Another application of X
D graphics is to visualize association rules for a market
basket analysis. For moredetail on association rules, see Wilhelm (
).In general,
an association rule is described in the form X
Y,inwhichX and Y are referred
to as the rule head and rule body, respectively. he method of obtaining the associa-
tion rules dependson the specification parameters, supportand confidence. In addi-
tion, it is di
cult to visualize association rules, because there are too many parame-
ters. Figure
.
shows a prototype of a representation of association rules. Items are
arranged according to item score by Hayashi's quantification method, type III. he
height and color of each bar indicate the confidence and the support, respectively.
he redder bars indicate high support and the bluer bars indicate low support. he
translucent plane represents a confidence level of
.
. Meaningful rules are there-
fore represented by the tall red bars. he status bar at the bottom on the right shows
informationabouttheruleselectedbythemousecursor(pointingfinger);therule
is
; the support is
.
; and the confidence is
.
.
GIS Applications
18.5.3
One of the most important fields that can benefit from the use of SVG is that of GIS
(geographic information system)web.GISapplications donotrequire simplyafunc-
tionthatdisplaysamap.Functionsthatenabletheenlargement/reduction/movement
ofthemapandthosethatdisplayinformation,suchasonroads,railroadsorfacilities,
arerequireddependingonthedemandsoftheuser.Furthermore,statistical informa-
tion on domains and points retrieved from databases associated with statistical sur-
veysandlocation-dependent statistical data ispresentedonthemap.Althoughmany
such systems have been designed, most have been built as web applications using
raster graphics or as Java applications, which is a somewhat problematic approach.
Applications that userastergraphics encounter issues related tothe costof preparing
large numbers of image files (all of the maps required for the system and maps that
