Proper statistical analysis is an absolutely essential tool for both clinicians and researchers attempting to implement evidence-based decisions. When analyzing reliability, statistical graphical representation is the best method. Other previously published error studies of 2D measurements, such as cephalometric landmarks, have inappropriately applied one-dimensional approaches, such as linear-or angular measurements. The aim of this present article is to illustrate a graphic presentation method that can be applied to two-dimensional (2D) data sets. We propose that this 2D visualization technique, that can visualize errors in both x-and y axes simultaneously, should be utilized when reporting the reliability of a 2D data set. Our prediction error analysis of soft tissue changes after orthognathic surgery will be presented as an example. By applying different colors to each ellipse, this method can also identify any between-group differences that may be present.