Three-dimensional histograms are used to visualize crosstabulations of values in two variables. They are considered a conjunction of two simple (i.e., univariate) histograms, combined such that the frequencies of co-occurrences of values on the two analyzed variables can be examined. In the most common format of this graph, a 3D bar is drawn for each �cell� of the crosstabulation table and the height of the bar represents the frequency of values for the respective cell of the table.

Histogram intervals or categorization can be defined for each variable by any of the options discussed in Methods of Categorization.

STATISTICA provides five styles for bivariate histograms: Box Plots, Contour Plots, Contour/Discrete, Spikes, and Surface Plots.

See also, Graphs - Bivariate Histograms and the Conceptual Overview for Bivariate Histograms.