Analyzing
time dependent data visually is a quick and effective way to identify
patterns and make comparisons. The Centers for Disease Control publishes
a weekly surveillance report during the flu season that contains a
number of graphical displays including bar charts and line graphs.
In this form, flu information is easily understood by both the general
public and health care professionals. Many states also publish weekly
flu surveillance reports through their websites.
The data plotted in
this case is the number of reported cases in each state and we are
limited to comparing time patterns between the two states. New York
has a larger population and as such would be expected to have a higher
number of seasonal flu cases. In order to compare the weekly flu
incidence between the two states, these raw counts would need to be
transformed to rates, such as number per 100,000 population.
Graph Builder is a very flexible platform that allows
a variety of graphs to be easily created. This case illustrated only
a few of the available options. Best practices in data visualization
such as equally scaled axes, proper labeling, and small multiples
are implemented in Graph Builder. Further discussion of best practices
in data visualization can be found in the seminal works of Tufte,
Cleveland, and Few.
When building data displays
it is important to design them to deliver the desired message to the
intended audience. Static displays such as those presented in this
case are appropriate for printed publications. Such displays need
to conform to publication standards, and these visualizations should
be geared to the publication’s target audience. In some circumstances,
stakeholders are interested in interacting with the data. In that
case, a dynamic dashboard to visualize the data would be more appropriate
to fulfill the user’s needs.