stacked bar chart Philippe Rocca-Serra Orlaith Burke Alejandra Gonzalez-Beltran Stacked bar chart is a bar which is used to compare overall quantities across items while showing the contribution of category to the total amount. Stacked bar chart can be used for highlighting the total as they visually aggregate all of the categories in a group while indicating a part to whole relationship. The downside is that it becomes harder to compare the sizes of the individual categories. adapter from http://www2.le.ac.uk/offices/ld/resources/numeracy/bar-charts and http://blog.visual.ly/how-groups-stack-up-when-to-use-grouped-vs-stacked-column-charts/ [last accessed: 2014-03-04] barplot(height....) set argument " beside = FALSE " http://stat.ethz.ch/R-manual/R-patched/library/graphics/html/barplot.html bar chart ready for release