Distortion estimators



IWT K_b = 4 mid-point estimators


P	δ		D^sig	∆D^sig		D^ref	∆D^ref

3	0.5	137.5	132.0
2	0.5	31.5	30.0	5.5	4.0
1	0.5	6.5	6.0	1.5	1.0
0	0.0	1.0	1.0	0.5	0.5