Graphics Reference
In-Depth Information
Figure
.
.
Cumulative times for riders in
Tour de France for the
stages. he axes have
a common scale and are aligned by their means. Each vertical line represents a stage, and they have
been plotted in date order. Source: http://www.letour.fr
cases in Toronto. Each column represents one combination of the four binary vari-
ables Gender, Employed, Citizen and Colour. he width of a column is proportional
to the number with that combination of factors. hose stopped who were not re-
leased later have been highlighted. Over
% of those stopped were male. Some of
the numbers of females in the possible eight combinations are toosmall todrawfirm
conclusions. Each pair of columns represents the variable colour, and the proportion
not released amongst the males is lower amongst the whites for all combinations of
otherfactors.hegeneraldeclineinthelevelofhighlighting acrossthemalecolumns
showsthat theproportionnotreleased islowerifthepersonisacitizen andlowerstill
if they are employed. Figure
.
shows the di
culties in displaying data of this kind
in a graphic for presentation. Colour, aspect ratio and size can make a big difference,
but labelling is the main problem.
Small Multiples and Trellis Displays
2.5.4
One way to avoid overloading a single large plot with information is to use a set of
smaller, comparable plots instead. his can be effective for subgroup analyses [e.g.
trellis displays for conditioning (Becker et al.,
)] or for geographic data [cf. mi-
cromaps Carr (
)]. A simple example is given in Fig.
.
. he boxplots on their
