Database Reference
In-Depth Information
Suppose the presenter wanted to talk about the total growth of BigBox stores
instead. A line chart showing the trends over time would be a better choice, as
shown in
Figure 12.33
.
In both cases, the noise and distractions within the chart have been removed. As a
result, the data in the bar chart for providing context has been deemphasized, while
other data has been made more prominent because it reinforces the key point as
stated in the chart's title.
12.3.5 Additional Considerations
As stated in the previous examples, the emphasis should be on simplicity when
creating charts and graphs. Create graphics that are free of chart junk and utilize
the simplest method for portraying graphics clearly. The goal of data visualization
should be to support the key messages being made as clearly as possible and with
few distractions.
Similar to the idea of removing chart junk is being cognizant of the data-ink
ratio.
Data-ink
refers to the actual portion of a graphic that portrays the data,
while
non-data ink
refers to labels, edges, colors, and other decoration. If one
imagined the ink required to print a data visualization on paper, the data-ink ratio
could be thought of as (data-ink)/(total ink used to print the graphic). In other
words, the greater the ratio of data-ink in the visual, the more data rich it is and
the fewer distractions it has [4].
Avoid Using Three-Dimensions in Most Graphics
One more example where people typically err is in adding unnecessary shading,
depth, or dimensions to graphics.
Figure 12.34
shows a vertical bar chart with
two visible dimensions. This example is simple and easy to understand, and the
focus is on the data, not the graphics. The author of the chart has chosen to
highlight the SuperBox stores in a dark blue color, while the BigBox bars in the
chart are in a lighter blue. The title is about the growth of SuperBox stores, and
the SuperBox bars in the chart are in a dark, high-contrast shade that draws the
viewer's attention to them.
