Database Reference
In-Depth Information
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Fig. 5.4
Number of Tweets generated per minute on November 15, 2011
using the method
GenerateDataTrend
defined in the class
ExtractDatasetTrend
and
summarized in Listing
5.4
.
5.2.1
Extending the Capabilities of Trend Visualization
A simple trendline provides only an overview of the data and cannot support
in-depth analysis. Operations such as zoom and filter can empower a user to
drill-down and investigate the data more effectively. There are two techniques which
can improve the user experience and add value to the visualization discussed above:
brushing & linking and focus+context. Together, they can be used to facilitate drill-
down analysis of information.
Brushing & Linking
Brushing and linking is a technique to effectively use
multiple views of the data to perform zoom and filter operations. In the collective
action of brushing and linking, multiple views are linked to each other, with each
view providing a different perspective of the data. Actions in the views are linked
by means of user interaction. Selecting a region in one view simultaneously affects
a change in the other view.
Focus+Context
Focus+context is a technique to enable drilling down into the data.
Trendlines provide an effective overview of some quantity, which in the case of
Fig.
5.4
, is the number of Tweets per minute. Focusing the view causes the view to
zoom into the data to provide information in greater detail. Context is the action of
de-magnifying to zoom out of the series at a particular point and it allows a user to
obtain the overview of the data.
