student (0.02) (0.03) (0.04) (0.02)
IG: Gender = female 0.06 *** 0.06 *** 0.06 ** 0.06 ***
(0.02) (0.02) (0.03) (0.01)
Black and African 0.20 *** 0.24 *** 0.24 *** 0.20 ***
American (0.04) (0.04) (0.06) (0.03)
Asian 0.04 ** 0.05 ** 0.05 * 0.03
(0.02) (0.02) (0.03) (0.02)
Hispanics 0.07 ** 0.09 ** 0.09 * 0.06 *
(0.03) (0.04) (0.06) (0.03)
Other races -0.03 -0.08 -0.09 -0.02
(0.06) (0.07) (0.10) (0.06)
hsize: Household size -0.02 *** -0.02 *** -0.02 ** -0.02 ***
(0.01) (0.01) (0.01) (0.01)
Constant 0.38 *** 0.37 *** 0.38 *** 0.35 ***
(0.06) (0.07) (0.10) (0.06)
Log likelihood -163 -396 -304 -117
Pseudo R-square 0.08 0.13 0.15
Estimated Coefficients
Tobit RE-Tobit Marginal
Effects
IPREF.. Strong brand 0.20 *** 0.19 *** 0.16
preference = 8,9,10 -0.02 -0.02 [0.01]
IP = E: Electronic 0.06 *** 0.06 *** 0.05
(0.03) (0.02) [0.01]
IP = C: Clothing 0.08 *** 0.08 *** 0.06
(0.02) (0.02) [0.01]
IP = P: Packaged food 0.04 * 0.04 ** 0.05
(0.02) (0.02) [0.01]
INC: Income per capita 0.002 * 0.002
(0.00) (0.00) 0.001
INC: Income square -0.00 -0.00 [0.00]
(0.00) (0.00)
age: Age -0.01 *** -0.01 *
(0.00) (0.01) -0.002
[age.sup.2]: Age square 0.00 ** 0.00 * [0.00]
(0.00) (0.00)
edu1: College and -0.09 *** -0.09 ** -0.07
above (0.03) (0.04) [0.01]
edu2: Current college 0.04 0.03 0.03
student (0.02) (0.04) [0.00]
IG: Gender = female 0.06 *** 0.06 ** 0.05
(0.02) (0.03) [0.01]
Black and African 0.22 *** 0.22 *** 0.19
American (0.04) (0.06) [0.02]
Asian 0.04 * 0.04 0.03
(0.02) (0.03) [0.00]
Hispanics 0.08 ** 0.08 [0.06 ]
(0.04) (0.06) [0.01]
Other races -0.06 -0.07
(0.07) (0.10)
hsize: Household size -0.02 *** -0.02 *** -0.02
(0.01) (0.01) [0.00]
Constant 0.33 *** 0.34 ***
(0.07) (0.10)
Log likelihood -346 -250
Pseudo R-square 0.24
Note: Figures in parentheses are White heteroskedastic consistent
standard errors and figures in brackets are standard errors of the
estimated marginal effects. Single, double, or triple asterisks
(*, **, ***) represent significance at the 1%, 5%, and 10 levels,
respectively.
Table 5. Estimation Results and Marginal Effects of the Ordered
Probit Models on the Stated WTP Ranges ([IW.sub.ik])
Estimated Marginal Effects On
Coefficients The OPROBIT Model
with Brand Preference
Independent P P
Variables: OPROBIT OPROBIT (IW = 1) (IW = 2)
IPREF Brand 0.70 *** -0.27 0.05
preference > 7 / (0.08) [0.03] [0.01]
IP=E: Electronic 0.58 *** 0.34 *** -0.14 0.03
(0.07) (0.08) [0.03] [0.01]
IP=C: Clothing 0.33 *** 0.33 *** -0.14 0.03
(0.08) (0.08) [0.02] [0.01]
IP=P: Packaged 0.07 * 0.13 ** -0.05 0.01
food (0.06) (0.06) [0.03] [0.01]
INC: Income per 0.01 0.01 -0.0016 0.0004
capita (0.01) (0.01)
[INC.sup.2]: Income -0.00 -0.00 [0.00] [0.00]
square (0.00) (0.00)
age: Age -0.04 * -0.04 ** 0.0036 0.0007
(0.04) (0.02)
[age.sup.2]: Age square 0.00 * 0.00 * [0.01] [0.00]
(0.00) (0.00)
edu1: College and -0.38 ** -0.30 * 0.12 -0.02
above
(0.17) (0.17) [0.06] [0.01]
edu2: Current 0.13 0.14 -0.06 0.01
college student (0.14) (0.14) [0.05] [0.01]
IG:Gender= 0.25 ** 0.26 ** -0.10 0.03
female (0.11) (0.11) [0.04] [0.01]
Black & African 0.96 *** 0.93 *** -0.31 -0.02
American
(0.21) (0.22) [0.06] [0.03]
Asian 0.19 * 0.15 -0.06 0.01
(0.13) (0.13) [0.05] [0.01]
Hispanics 0.47 ** 0.44 ** -0.17 0.02
(0.20) (0.22) [0.08] [0.01]
Other races -0.29 -0.24 0.10 -0.03
(0.61) (0.40) [0.16] [0.06]
Hsize: Household -0.10 -0.06 0.02 -0.01
size (0.40) (0.04) [0.02] [0.00]
Marginal Effects On The OPROBIT Model
with Brand Preference
Independent P P P P
Variables: (IW = 3) (IW = 4) (IW = 5) (IW = 6)
IPREF Brand 0.08 0.06 0.04 0.04
preference > 7 [0.01] [0.01] [0.01] [0.01]
IP=E: Electronic 0.04 0.03 0.02 0.02
[0.01] [0.01] [0.01] [0.01]
IP=C: Clothing 0.04 0.03 0.02 0.02
[0.01] [0.01] [0.01] [0.01]
IP=P: Packaged 0.01 0.01 0.01 0.01
food [0.01] [0.00] [0.00] [0.00]
INC: Income per 0.0004 0.0003 0.0002 0.0003
capita
[INC.sup.2]: Income [0.00] [0.00] [0.00] [0.00]
square
age: Age -0.001 -0.0007 -0.0005 -0.007
[age.sup.2]: Age square [0.00] [0.00] [0.00] [0.00]
edu1: College and -0.04 -0.02 -0.02 -0.02
above
[0.02] [0.02] [0.01 [0.01]
edu2: Current 0.02 0.01 0.01 0.01
college student [0.02] [0.01] [0.01] [0.01]
IG:Gender= 0.03 0.02 0.01 0.01
female [0.01] [0.01] [0.01] [0.00]
Black & African 0.09 0.08 0.07 0.09
American
[0.02] [0.02] [0.02] [0.04]
Asian 0.02 0.01 0.01 0.01
[0.02] [0.01] [0.01] [0.01]
Hispanics 0.05 0.04 0.03 0.03
[0.02] [0.02] [0.02] [0.02]
Other races -0.03 -0.02 -0.01 -0.01
[0.05] [0.02] [0.01] [0.01]
Hsize: Household -0.01 -0.00 -0.00 -0.00
size [0.00] [0.00] [0.00] [0.00]
Cut Estimated
Points Cut Points
[C.sub.1] -0.65 -0.52
(0.43) (0.44)
[C.sub.2] 0.24 0.41
(0.42) (0.44)
[C.sub.3] 0.74 0.93
(0.42) (0.43)
[C.sub.4] 1.11 1.32
(0.42) (0.43)
[C.sub.5] 1.50 1.74
(0.41) (0.42)
No. of OBS 1208 1207
Pseudo [R.sup.2] 0.05 0.07
Cut Probability
Points
[C.sub.1] prob([IW.sub.ik] = 1) = prob(0 [less than or
equal to] [W.sup.*.sub.ik] < [C.sub.1])
[C.sub.2] prob([IW.sub.ik] = 2) = prob([C.sub.1] [less than or
equal to] [W.sup.*.sub.ik] < [C.sub.2])
[C.sub.3] prob([IW.sub.ik] = 3) = prob([C.sub.2] [less than or
equal to] [W.sup.*.sub.ik] < [C.sub.3])
[C.sub.4] prob([IW.sub.ik] = 4) = prob([C.sub.3] [less than or
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