Table 2. Mean estimates of the coefficient of double reduction α and standard deviations of estimates (in parentheses), relative to true values.

			Relative mean estimated α
r	q	α	Five-parameter model	Luo et al. (2004)	S. S. Wu et al. (2001)
0.01	0.01	0.00057	1.07 (0.029)	1.07 (0.029)	1.11 (0.033)
0.01	0.10	0.00570	0.97 (0.027)	0.97 (0.028)	0.98 (0.031)
0.01	0.30	0.01708	0.97 (0.028)	0.98 (0.028)	0.99 (0.032)
0.10	0.01	0.00057	1.07 (0.029)	1.07 (0.029)	1.11 (0.033)
0.10	0.10	0.00570	0.97 (0.028)	0.97 (0.028)	0.98 (0.031)
0.10	0.30	0.01708	0.97 (0.028)	0.98 (0.028)	0.99 (0.032)
0.30	0.01	0.00057	1.07 (0.029)	1.07 (0.029)	1.11 (0.033)
0.30	0.10	0.00570	0.97 (0.027)	0.97 (0.028)	0.98 (0.031)
0.30	0.30	0.01708	0.97 (0.028)	0.98 (0.028)	0.99 (0.032)

r and q are varied as indicated; τ, p_DP, and p_PC are fixed to 0.67, 0.21, and 0.34, respectively; the true α is determined by q, τ, and p_PC through Equation 1.