Table 3.

Relative frequencies and conditional relative frequencies of metameric pairs of surfaces in natural scenes, calculated with color-difference formula CIEDE2000,^{3, 27} adaptation model CMCCAT2000,²⁴ and nominal discrimination threshold ΔE^thr = 1.0^a

			Criterion degree of metamerism na
Illuminants	Scene	Estimate	0	1	2	3	4
25,000 K–4000 K	vegetated	unconditional	−2.74	−3.08	−3.86	−4.58	−5.33
			(0.36)	(0.33)	(0.49)	(0.65)	(0.92)
		conditional		−0.34	−1.13	−1.84	−2.54
				(0.15)	(0.43)	(0.69)	(0.99)
	nonvegetated	unconditional	−2.63	−3.09	−4.17	−5.09	−6.05
			(0.35)	(0.28)	(0.44)	(0.69)	(0.84)
		conditional		−0.47	−1.54	−2.44	−3.29
				(0.16)	(0.56)	(0.78)	(0.92)

^aOther details as for Table 2.