Graphics Reference
In-Depth Information
he linked views paradigm is a method of taking multiple simple views of data and
allowing interactions with one to modify the display of data in all the linked views.
A simple example is that selecting a data case in one view shows that data case high-
lighted in all other views. In this section we define the underlying methodology and
show how it has been applied historically and how it can be extended to provide
enhanced power. In particular we focus on displays of aggregated data and linking
domain-specific views such as graph layouts and maps to statistical views.
Motivation: Why Use Linked Views?
9.1
A “data view” can be thought of as anything that gives the user a way of examin-
ing data so as to gain insight and understanding. A data view is usually thought of as
abarchart,scatterplot, orothertraditional statistic graphic,butweusethetermmore
generally, including “views” such as a display of the results of a regression analysis,
a neural net prediction, or a set of descriptive statistics. A plot of geographic infor-
mation, such as a map of a country, is a data view. A node and edge graph displaying
interrelationships between relatives (more commonly known as a “family tree”) is
adataview.AprintoutoftheR
value from a regression is a data view, albeit a very
simpleone.Viewsofdata arealsoknown asgraphs, charts,diagrams, plots,and visu-
alizations, but each of those terms has connotations that can restrict howwe think of
a linked view. hus, in this chapter, we use the simple term “data view” - something
that allows us to view data.
A linked data view is a data view that communicates with another view. If a mod-
ification is made to one of the views, the other view will change its appearance in
reaction to the modification. A simple example of linked data views is a scroll bar in
a text editor that is linked to the text view. he scroll bar has a “thumb” that shows
which part of the document is being displayed. When the user modifies the scroll
bar by dragging the thumb around, the text view updates to show that portion of
the document. his example is presented first to highlight the ubiquity of the linked
views approach;thelinked viewsparadigm isusedinstandard user interfaces (Apple
Computer,
;Microsot,
)andingamesotware(Maxis,
)aswellinmore
specifically data-analytic sotware.
Figure
.
shows a moredirectly data-analytic version of linked views. hedataset
usedisdescribedintheappendix,whichgivesdetailsofthedatausedtogenerateeach
figureinthischapter.hedataaretakenfromanarchiveofbaseballstatisticscollected
and
. In this figure we are interested in comparing players' salaries to their
performance and so create a scatterplot showing the relationship between salary and
batting average(thesinglemostcommonlyusedmeasureofaplayer'sbatting ability).
We create a histogram of the year for this dataset (which incidentally shows us that
salary data only became available starting in
) and then select the histogram bars
