Table 2. Model I estimated GEE coefficients for corn field acreage allocation equations by field
structural practice (technology), and by conservation program participation.
[Model I: (Aj,p) = f(normalized input prices, technology class & installation variables)].
Equation/Variable______________________ |
Program Non-Participants_____ |
_______Program Participants_______ | ||
Estimate______ |
T-Tests b |
_____Estimate________ |
T-Tests | |
Model I | ||||
Constant |
2.8045 |
1.13 |
5.6368 *** |
1.71 |
Corn Field Acres Planted (with): EQ1: No structural practices: a | ||||
N price |
119.8528 * |
3.78 |
- 50.6681 |
- 0.78 |
Ag. Wage |
0.4036 |
1.41 |
- 2.3509 * |
- 3.88 |
Diesel price |
- 21.9501 * |
- 3.48 |
16.7863 |
1.43 |
EQ2: Only infield structures: a | ||||
N price |
- 66.1984 * |
- 2.48 |
2.9938 |
0.07 |
Ag. Wage |
0.1891 |
0.76 |
0.2749 |
0.61 |
Diesel price |
8.9845 ** |
1.88 |
- 4.7731 |
- 0.59 |
EQ3: Only perimeter-field structures: a | ||||
N price |
- 13.4583 |
- 0.93 |
29.6982 |
0.91 |
Ag. Wage |
- 0.3608 * |
- 3.83 |
1.1760 * |
4.73 |
Diesel price |
5.8741 ** |
1.96 |
- 13.4898 * |
- 2.27 |
EQ4: Both structural practices: a | ||||
N price |
- 4.4147 |
- 0.82 |
- 24.6257 |
- 1.25 |
Ag. Wage |
0.1283 |
0.95 |
0.1979 |
0.52 |
Diesel price |
2.2566 |
1.17 |
0.1968 |
0.04 |
Technology class variables: |
Units_______________ |
Estimate |
T-tests_________ | |
Only Infield structures |
(Yes = 1) |
- 1.2985 |
- 0.36 | |
Only perimeter-field structures |
(Yes = 1) |
- 4.3706 |
- 1.31 | |
Both structures |
(Yes = 1) |
- 4.7776 *** |
- 1.56 | |
Installation dummy variables: | ||||
Installed in 2005 |
(Yes = 1) |
- 0.0131 |
- 0.18 | |
Installed within last 10 years |
(Yes = 1) |
0.0128 |
0.31 | |
Installed prior to 1990 |
(Yes = 1) |
- 0.0106 |
- 0.04 | |
Log Likelihood Value (L1) = - 2906.1413 |
R2 = 0.09 |
Corn field observations (weighted) with: | ||
# of corn farms surveyed c = 380 [for 39 million planted corn acres] |
only infield |
conservation structures = 25.9 % | ||
Conservation program participants = 15 % |
only perimeter conservation structures |
= 9.0 % | ||
Conservation program non-participants = 85 % |
both infield |
and perimeter structures = |
4.1 % |
a State average per unit prices (2005) for nitrogen ($/lb.), agricultural wage ($/hr.), and diesel ($/gal.) were normalized using
State average 2005 corn price ($/bu.).
b Critical values for the t tests are 1.52 (***), 1.76 (**), and 2.14 (*) for the 15 %, 10 %, and 5 % significance levels, respectively.
Standard errors were computed using the delete-a-group Jackknife approach (Dubman, 2000).
c Surveyed States for the 2005 Ceap-Arms for corn included IN, IA, IL, and NE.
Note: Infield conservation structural practices included terraces, grassed waterways, vegetative buffers, contour buffers, filter
strips, and grade stabilization structures. Perimeter-field conservation structural practices included hedgerow plantings,
stream-side forest buffers, stream-side herbaceous buffers, windbreaks or herbaceous wind barriers, field borders, and
critical area plantings.
Source: 2005 CEAP-ARMS Phase II data (for corn), Economic Research Service, USDA.
28
More intriguing information
1. Public infrastructure capital, scale economies and returns to variety2. Standards behaviours face to innovation of the entrepreneurships of Beira Interior
3. Inflation and Inflation Uncertainty in the Euro Area
4. Life is an Adventure! An agent-based reconciliation of narrative and scientific worldviews
5. The name is absent
6. The name is absent
7. APPLYING BIOSOLIDS: ISSUES FOR VIRGINIA AGRICULTURE
8. The name is absent
9. The problem of anglophone squint
10. Better policy analysis with better data. Constructing a Social Accounting Matrix from the European System of National Accounts.