URI: http://www.qualityml.org/1.0/domain/DifferentialErrors2DThreshold
Name: 2D Differential Error Measure with a threshold
Alternative names:  

Given a measured xmi and ymi coordinate and a xti and yti, considered to represent the truth, the arthimetic errors for two dimensional positional values are calculated as:

2D Differential Error Population

selecting the values:
if level="above": SQRT(exi2+eyi2)>emax
if level="below": SQRT(exi2+eyi2)<emax

Source: ISO 19157