Variable | OLS | IVREG2H | ||
---|---|---|---|---|
Coefficient | Std error | Coefficient | Std error | |
Improved seeds | 0.032 | 0.055 | 0.104 | 0.146 |
Inorganic fertilizer | 0.324*** | 0.034 | 0.305* | 0.179 |
Organic fertilizer | 0.019 | 0.040 |  − 0.427*** | 0.140 |
Legume intercropping |  − 0.092** | 0.038 | 0.034 | 0.097 |
Growing season rainfall (mm) | 0.000* | 0.000 | 0.000 | 0.000 |
Start of wettest dekad in 2018 |  − 0.017** | 0.008 |  − 0.019* | 0.010 |
Household size | 0.027 | 0.029 | 0.047 | 0.034 |
Dependency ratio | 0.043*** | 0.014 | 0.042*** | 0.016 |
Gender |  − 0.001 | 0.001 |  − 0.001 | 0.001 |
Age | 0.156*** | 0.051 | 0.161*** | 0.056 |
Education |  − 0.004 | 0.004 |  − 0.007* | 0.005 |
Off farm |  − 0.044 | 0.033 |  − 0.031 | 0.041 |
Wage work |  − 0.104** | 0.053 |  − 0.109* | 0.063 |
Extension | 0.093** | 0.042 | 0.105** | 0.048 |
Own plot | 0.032 | 0.039 | 0.055 | 0.043 |
Erosion control |  − 0.132 | 0.139 |  − 0.215 | 0.139 |
Steep slope |  − 0.033 | 0.038 |  − 0.039 | 0.041 |
Irrigation | 0.244*** | 0.094 | 0.268*** | 0.099 |
Distance to market | 0.000 | 0.000 |  − 0.001 | 0.000 |
Nutrient constraint |  − 0.148*** | 0.025 |  − 0.134*** | 0.028 |
NDVI in 2018 | 1.805*** | 0.406 | 1.635*** | 0.561 |
Distance to household | 0.002 | 0.004 | 0.002 | 0.004 |
Wealth Index | 0.078*** | 0.030 | 0.093*** | 0.036 |
Agric capital index | 0.019 | 0.015 | 0.030 | 0.019 |
Tropical livestock unit |  − 0.010*** | 0.004 |  − 0.008 | 0.005 |
North Central | 0.011 | 0.139 |  − 0.028 | 0.162 |
North East |  − 0.398*** | 0.140 |  − 0.409** | 0.170 |
North West | 0.040 | 0.144 | 0.156 | 0.195 |
South East | 0.278* | 0.156 | 0.268 | 0.183 |
South West | 0.613*** | 0.164 | 0.545*** | 0.194 |
Constant | 11.856*** | 0.283 | 11.966*** | 0.374 |
Sample size | 5,616 | Â | 5616 | Â |
R2 | 0.070 | Â | 0.050 | Â |
Wald | 15.8*** | Â | 10.54*** | Â |
Underidentification test | Â | Â | 136.19** | Â |
Weakidentification test | Â | Â | 2.673*** | Â |
Overidentification test (Hansen J statistic) | Â | 56.60 | Â |