PERCENTILEDISC

PERCENTILEDISC is a conceptual data visualization format designed to represent distribution percentiles on a circular disk. It encodes percentile information in a polar layout so that the progression from low to high values can be read around the circumference and, optionally, outward from the center.

In a typical implementation, a set of percentile values is computed for one or more datasets (for example, 0th, 10th, 25th, 50th, 75th, 90th, and 100th percentiles). Each percentile rank p is assigned an angular position θ = 2πp/100 on the disk, while the corresponding data value v(p) is used to determine the radial distance r after normalization. The resulting polyline or area trace represents how values increase across percentile ranks. When multiple groups are analyzed, their percentile traces can be overlaid for visual comparison.

Interpretation focuses on the shape and density of the percentile curve. A steep rise, asymmetry, or pronounced curvature can reveal skewness, tails, or concentration of values. Similar shapes across groups may indicate comparable distributions, while divergent curves highlight differences in central tendency or dispersion. Optional enhancements include layering confidence bands, using color to distinguish groups, or integrating additional markers for key percentiles.

Variants of the approach include radial bands to indicate fixed percentile ranges, or stacked disks to compare multiple distributions within a single composite diagram. Limitations include potential accessibility issues for readers unfamiliar with polar plots and the need for careful normalization when comparing datasets of different scales. See also: percentile, quantile, circular statistics, data visualization.