Graphics Reference
In-Depth Information
events inthedisplayneedstobeselectedwithcare.Inthisexample,thecriterionused
was to show only those events that had at least
% incidence in treatment B.
his type of panel display is useful for randomized trials with two or more treat-
ment arms. When a study has more than two treatment arms, consider separate sets
of graphs for each pairwise comparison of interest.
Summary
6.9
Wehaveillustrated manywaysinwhichsetsofgraphs arecoordinated inastructured
manner to increase the amount of information that they carry jointly. he principle
of construction used in all the examples is the use of multiple panels placed in a rect-
angular structure defined by the crossing of sets of labels. While a set is oten the set
of levels of a factor, it may also be a set of different variables, of different functions
of the same variable, of different functions of the data, or of different models applied
to the data. We showed examples with several applications of scatterplot matrices,
with a series of displays of case statistics used as diagnostics in regression analysis,
with interactions of several factors in analysis of variance setting, with boxplots used
in conjunction with tabular displays of the same information, and with a graphical
display of incidence and relative risk for adverse effects. In all cases, the use of struc-
tured sets of graphs enhances the ease of presenting and receiving the information
revealed by the analysis.
File Name Conventions
6.10
All examples in this article were constructed with code from the referenced files in
the HH online files Heiberger and Holland (
).
References
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