Visualization for Interval Data

Interval data are widely used in many fields, notably in economics, industry, and health areas. Analogous to the scatter plot for single-value data, the rectangle plot and cross plot are the conventional visualization methods for the relationship between two variables in interval forms. These methods do not provide much information to assess complicated relationships, however. In this paper, we propose two visualization methods: Segment and Dandelion Plots. They offer much more information than the existing visualization methods and allow us to have a much better understanding of the relationship between two variables in interval forms. A general guide for reading these plots is provided. Relevant theoretical support is developed. Both empirical and real data examples are provided to demonstrate the advantages of the proposed visualization methods. Supplemental materials for this article are available online.