Table 4.

Mean willingness to pay estimated with probit, bivariate, or Krinsky and Robb methods.

Method		Average WTPa		Mean difference (95% CI)		CI/WTP
Probit and bivariate methods
	DCb (N=199)		4033.26		4386.01 (1840.25 to 6226.26)		1.09
	DC-OEc (N=230)		1857.90		1945.1 (885.35 to 2830.45)		1.05
	MBDCd—probit (N=1245)		1630.63		556.64 (1352.31 to 1908.95)		0.34
	MBDC—definitely yes (N=181)		1516.73		2796.86 (118.30 to 2915.16)		1.84
	MBDC—probably yes (N=181)		1871.22		4926.29 (−591.92 to 4334.37)		2.63
	MBDC—do not know (N=181)		2514.49		3032.39 (998.29 to 4030.68)		1.21
Krinsky and Robb’s methods
	DC (N=199)		4750.18		6985.57 (3911.67 to 10,897.24)		1.47
	DC-OE (N=230)		1857.90		1924.93 (895.44 to 2820.37)		1.04
	MBDC—probit (N=1245)		1701.37		896.51 (1103.43 to 1999.94)		0.53

^aWTP: willingness to pay.

^bDC: dichotomous choice.

^cDC-OE: dichotomous choice followed by an open-ended question.

^dMBDC: multiple-bounded discrete choice.