  Pie charts were first published in 1801 by William Playfair and have caused
some controversy since. Despite the suggestions of many experts against their
use, several empirical studies have shown that pie charts are at least as good
as alternatives. From Brinton to Few on one side and Eells to Kosara on the
other, there appears to have been a hundred-year war waged on the humble pie.
In this paper a set of experiments are reported that compare the performance of
pie charts and horizontal bar charts with various visual cues. Amazon's
Mechanical Turk service was employed to perform the tasks of estimating
segments in various part-to-whole charts. The results lead to recommendations
for data visualization professionals in developing dashboards.
