In scatterplots with many overlapping data points, the relative frequencies of the number of points represented by a single plot position (e.g., {x, y} coordinate pair) can be indicated with "bubbles," i.e., circles of varying sizes. This is illustrated in the following example:

Note that STATISTICA supports the bubble-representation of multiple overlapping data points in 2D (see above) and 3D:

See also 2D Scatterplot and Graphs - 2D Scatterplots.