Table 1. SUR Estimation Results for U.S. Soybean Export Equations, 1963-86a
VariabIesZdata |
EC-9 |
Japan |
Spain |
Taiwan |
South |
Rest of |
Constant |
2,391,000 |
435,600 |
1,676,000 |
751,000 |
38,670 |
-2,479,000 |
(1.22) |
(∙58) |
(2.96)" |
(2.10)* |
(■49) |
(-3.17)" | |
Real U.S. soybean |
-5,469 |
-3,045 |
-1,918 |
-877.6 |
-1,462 |
2,452 |
price, Rotterdamc |
(-∙98) |
(-2.42)* |
(-■95) |
(-1.48) |
(-2.52)∙ |
(1.23) |
Real U.S. soybean meal 4,258 |
3,522 |
287.3 |
304.5 |
889.3 |
-2,659 | |
price, Rotterdamc |
(■89) |
(3.02)" |
(.17) |
(■52) |
(1.95)* |
(-1∙56) |
Pork production in |
1.042 |
2.338 |
.786 |
1.807 |
1.967 |
.949 |
importing country0 |
(5.52)” |
(7.37)" |
(3.35)" |
(13.73)" |
(7.99)" |
(9.03)" |
Real exchange rate |
-37,080 |
981.6 |
-8,710 |
-4,180 |
564.2 |
23,290 |
index |
(-3.66)" |
(∙30) |
(-2.71)" |
(-3.04)" |
(■56) |
(4.29) |
R2 |
.71 |
.92 |
.54 |
.95 |
.76 |
.78 |
Durbin-Watson |
2.01 |
2.00 |
1.71 |
2.22 |
1.76 |
1.84 |
Fβ |
366" |
684" |
- 341" |
759" |
348" |
354” |
, t-values in parentheses. Significance levels (one-tailed test with 19 degrees of freedom, two-tailed test for constant): ’ = 5 percent, " = 1
percent.
b Mexico, Portugal, Israel, Switzerland, Canada, Norway, Greece, Indonesia, and Egypt.
° Jan.-Dec. average, dollars per metric ton, deflated by U.S. CPI.
° Metrictons.
β Test of significance of model (unrestricted SUR estimation compared with restriction of estimators = Oin each equation in turn).
Table 2. OLS and 2SLS Estimation Results3
Estimator
VanabIesZdata |
OLS ........... |
— 2SLS system.............. | ||
Dependent variable |
U.S. soybean |
Real U.S. |
Real U.S. |
U.S. soybean |
Constant |
6,324,000 (1.44) |
111.4 (1.78) |
155.6 (2.50)* |
9,609,000 |
U.S. soybean exports |
— |
-.0000019 (-■76) |
-.0000016 (-■56) |
— |
Real U.S. soybean |
-13,950 |
.6846 (4.03)" |
— |
-4,127c |
Real U.S. soybean meal |
7,015 |
— |
.4308 (2.17)* |
-23,360 ° |
Pork production in |
1.193 (5.82)" |
— |
— |
1.157 (5.04)" |
Real exchange rate |
-64,630 (-2.60)" |
— |
— |
-60,430 (-2-19)∙ |
R2 |
.87 |
.39 |
.11 |
— |
Durbin-Watson |
2.06 |
— |
— |
— |
Ff |
30" |
5.82" |
1.67 |
— |
Degrees of freedom |
19 |
22 |
22 |
19 |
a t-values in parentheses. Significance levels (two-tailed test on constants and instrument equations, one-tailed test on other variables): ' =
5 percent, ** = 1 percent. In the price (instrument) equations, the dependent variable is lagged 1 year on the right-hand side.
b Nineteen countries listed in Appendix.
c Estimate of parameter on instrumental variable.
a Jan.-Dec. average, dollars per metric ton, deflated by U.S. CPI.
β Metrictons.
1 Test of significance of model [R2∕no. of variables]∕[(1 - R2)∕(no. of observations - no. of variables)].
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