Table 1.

Coefficients and their corresponding p-values of the gradient used on the computer generated phantom.

Coefficient	Applied Value	Calculated Value (noise σ2 = 25)	p-value (noise σ2 = 25)	Calculated Value (noise σ2 = 100)	p-value (noise σ2 = 100)
c(x)	1.17×10−2	(1.17±0.11)×10−2	0.99	(1.15±0.15)×10−2	0.74
c(y)	1.17×10−2	(1.17±0.07)×10−2	0.91	(1.09±0.16)×10−2	0.18
c(xy)	0	(−0.39±1.56)×10−5	0.54	(−0.55±2.19)×10−5	0.54
c(x2)	−4.58×10−2	(−4.48±0.54)×10−5	0.64	(−4.57±0.76)×10−5	0.98
c(y2)	−4.58×10−2	(−4.45±0.29)×10−5	0.27	(−4.17±0.67)×10−5	0.14
c(x2y)	0	(0.23±7.95)×10−8	0.94	(3.19±9.62)×10−7	0.42
c(xy2)	0	(−0.22±5.19)×10−8	0.92	(0.23±8.00)×10−7	0.94
c(x2y2)	0	(0.58±2.62)×10−10	0.58	(−0.28±2.88)×10−10	0.81

σ² = variance