| Literature DB >> 28148997 |
Simone Verkaart1, Bernard G Munyua2, Kai Mausch2, Jeffrey D Michler3.
Abstract
We analyse the impact of improved chickpea adoption on welfare in Ethiopia using three rounds of panel data. First, we estimate the determinants of improved chickpea adoption using a double hurdle model. We apply a control function approach with correlated random effects to control for possible endogeneity resulting from access to improved seed and technology transfer activities. To instrument for these variables we develop novel distance weighted measures of a household's neighbours' access to improved seed and technology transfer activities. Second, we estimate the impact of area under improved chickpea cultivation on household income and poverty. We apply a fixed effects instrumental variables approach where we use the predicted area under cultivation from the double hurdle model as an instrument for observed area under cultivation. We find that improved chickpea adoption significantly increases household income while also reducing household poverty. Finally, we disaggregate results by landholding to explore whether the impact of adoption has heterogeneous effects. Adoption favoured all but the largest landholders, for who the new technology did not have a significant impact on income. Overall, increasing access to improved chickpea appears a promising pathway for rural development in Ethiopia's chickpea growing regions.Entities:
Keywords: Control function; Ethiopia; Improved chickpea; Poverty; Technology adoption
Year: 2017 PMID: 28148997 PMCID: PMC5268341 DOI: 10.1016/j.foodpol.2016.11.007
Source DB: PubMed Journal: Food Policy ISSN: 0306-9192 Impact factor: 4.552
Descriptive statistics improved chickpea adoption.
| 2006/07 | 2009/10 | 2013/14 | ||||
|---|---|---|---|---|---|---|
| Mean | s.d. | Mean | s.d. | Mean | s.d. | |
| Chickpea (yes = 1) | 0.655 | 0.476 | 0.805 | 0.396 | 0.881 | 0.324 |
| Improved variety (1 = yes) | 0.312 | 0.464 | 0.630 | 0.483 | 0.790 | 0.407 |
| Improved chickpea area (ha) | 0.172 | 0.390 | 0.327 | 0.414 | 0.425 | 0.427 |
| Improved chickpea seed (kg) | 34.23 | 79.27 | 60.70 | 80.05 | 89.60 | 101.8 |
| Improved chickpea share area (%) | 5.925 | 11.67 | 12.11 | 12.96 | 18.90 | 14.24 |
| Improved chickpea share income (%) | 7.023 | 13.80 | 15.84 | 16.94 | 16.23 | 13.21 |
| Observations | 606 | 606 | 606 | |||
| Improved variety (1 = yes) | 0.476 | 0.500 | 0.783 | 0.413 | 0.897 | 0.304 |
| Improved chickpea area (ha) | 0.263 | 0.457 | 0.406 | 0.425 | 0.482 | 0.423 |
| Improved chickpea seed (kg) | 52.25 | 93.04 | 75.38 | 82.78 | 101.7 | 102.7 |
| Improved chickpea share area (%) | 9.044 | 13.41 | 15.03 | 12.82 | 21.45 | 13.24 |
| Improved chickpea share income (%) | 10.72 | 15.85 | 19.68 | 16.77 | 18.42 | 12.56 |
| Observations | 397 | 488 | 534 | |||
Note: Panel A displays means and standard deviations of improved chickpea adoption indicators by year for the balanced sample. Panel B displays means and standard deviations of improved chickpea adoption indicators by year for households that grow chickpeas.
Socio-economic characteristics of adopters and non-adopters.
| 2006/07 | 2009/10 | 2013/14 | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Non-adopter | Adopter | Non-adopter | Adopter | Non-adopter | Adopter | ||||
| Household size (no.) | 6.08 | 6.76 | ⁎⁎⁎ | 6.00 | 6.59 | ⁎⁎⁎ | 5.63 | 5.81 | |
| Dependents (%) | 42.9 | 45.4 | 39.0 | 40.9 | 39.9 | 34.9 | ⁎⁎ | ||
| Male head (yes = 1) | 0.93 | 0.96 | 0.94 | 0.95 | 0.91 | 0.91 | |||
| Education head (years) | 1.59 | 1.98 | ⁎ | 1.87 | 1.99 | 2.14 | 1.8 | ||
| Age head (years) | 46.3 | 47.9 | 49.3 | 48.1 | 50.3 | 52.0 | |||
| Total net income (USD) | 4541 | 7760 | ⁎⁎⁎ | 4145 | 7008 | ⁎⁎⁎ | 3404 | 4696 | ⁎⁎⁎ |
| Income per capita (USD) | 837 | 1232 | ⁎⁎⁎ | 806 | 1175 | ⁎⁎⁎ | 670 | 885 | ⁎⁎⁎ |
| Land owned (ha) | 2.01 | 2.67 | ⁎⁎⁎ | 2.00 | 2.41 | ⁎⁎⁎ | 1.94 | 2.16 | ⁎ |
| Value assets (USD) | 363 | 477 | ⁎⁎ | 325 | 376 | ⁎ | 493 | 722 | ⁎⁎⁎ |
| Poor household (<$1.25) | 0.28 | 0.11 | ⁎⁎⁎ | 0.37 | 0.20 | ⁎⁎⁎ | 0.48 | 0.27 | ⁎⁎⁎ |
| Poor household (<$2.00) | 0.57 | 0.32 | ⁎⁎⁎ | 0.58 | 0.39 | ⁎⁎⁎ | 0.70 | 0.54 | ⁎⁎⁎ |
| Observations | 417 | 189 | 224 | 382 | 127 | 479 | |||
Significance of t-tests are reported as ⁎p < 0.10, ⁎⁎p < 0.05, ⁎⁎⁎p < 0.01.
Fig. 1Poverty trends and income per capita in real and nominal Ethiopian birr.
Fig. 2Bivariate density of mean real income per capita (constant 2005 USD PPP).
Descriptive statistics for variables used in the econometric analysis.
| 2006/07 | 2009/10 | 2013/14 | ||||
|---|---|---|---|---|---|---|
| Mean | s.d. | Mean | s.d. | Mean | s.d. | |
| Distance to neighbours (km) | 94.54 | 173.0 | 94.54 | 173.0 | 94.54 | 173.0 |
| Technology transfer (1 = yes) | 0.013 | 0.114 | 0.127 | 0.333 | 0.150 | 0.358 |
| Distance to technology transfer (km) | 1.079 | 4.390 | 8.673 | 23.50 | 12.05 | 28.39 |
| Lag weighted dist. tech. transfer (IV) | – | – | 0.013 | 0.039 | 0.124 | 0.151 |
| Access to improved seed (yes = 1) | 0.195 | 0.396 | 0.195 | 0.396 | 0.186 | 0.390 |
| Distance to improved seed (km) | 17.32 | 36.46 | 18.47 | 42.10 | 21.54 | 48.15 |
| Lag weighted distance seed (IV) | – | – | 0.191 | 0.221 | 0.201 | 0.184 |
| Age head (years) | 46.81 | 12.08 | 46.81 | 12.08 | 46.81 | 12.08 |
| Education head (years) | 1.713 | 2.647 | 1.713 | 2.647 | 1.713 | 2.647 |
| Male head (1 = yes) | 0.936 | 0.246 | 0.942 | 0.233 | 0.914 | 0.280 |
| Household size (no.) | 6.295 | 2.250 | 6.368 | 2.358 | 5.772 | 2.089 |
| Dependents (%) | 43.70 | 20.49 | 40.21 | 19.62 | 35.98 | 21.60 |
| Off-farm income (1 = yes) | 0.276 | 0.447 | 0.246 | 0.431 | 0.282 | 0.450 |
| Land owned (ha) | 2.215 | 1.308 | 2.257 | 1.299 | 2.122 | 1.281 |
| Initial asset ownership (USD) | 398.4 | 560.7 | 398.4 | 560.7 | 398.4 | 560.7 |
| Walking distance to market (min) | 196.5 | 84.50 | 196.5 | 84.50 | 196.5 | 84.50 |
| Average rainfall past 5 seasons (mm) | 598.0 | 47.65 | 622.4 | 52.93 | 599.2 | 50.91 |
| St. dev. rainfall past 5 seasons (mm) | 97.70 | 15.50 | 57.85 | 12.64 | 81.18 | 12.04 |
| Black soil (yes = 1) | 0.969 | 0.174 | 0.969 | 0.174 | 0.969 | 0.174 |
| Sandy soil (yes = 1) | 0.777 | 0.416 | 0.777 | 0.416 | 0.777 | 0.416 |
| Mixed soil (yes = 1) | 0.246 | 0.431 | 0.246 | 0.431 | 0.246 | 0.431 |
| Observations | 606 | 606 | 606 | |||
Adoption decision: Cragg’s double hurdle model using correlated random effects estimation.
| Technology transfer and seed access exogenous | Technology transfer and seed access endogenous | |||
|---|---|---|---|---|
| (1) | (2) | (3) | (4) | |
| Access to technology transfer | 6.370∗∗∗ | 0.051 | −0.362 | 0.436∗∗∗ |
| (yes = 1) | (1.337) | (0.032) | (1.179) | (0.163) |
| Generalized residual access | – | – | 0.608 | −0.233∗∗ |
| Technology transfer | (0.650) | (0.092) | ||
| Access to improved | 0.663∗∗ | 0.003 | 1.608 | 0.181 |
| Seed (yes = 1) | (0.265) | (0.038) | (2.013) | (0.194) |
| Generalized residual access seed | – | – | 3.026∗∗∗ | −0.074 |
| (1.013) | (0.111) | |||
| Age head (yrs) | −0.006 | −0.002∗ | −0.020∗∗∗ | −0.001 |
| (0.006) | (0.001) | (0.007) | (0.002) | |
| Education head (yrs) | 0.002 | 0.014∗∗ | 0.023 | 0.014∗∗ |
| (0.028) | (0.007) | (0.029) | (0.007) | |
| Male head (yes = 1) | 0.208 | −0.053 | 0.507 | −0.038 |
| (0.693) | (0.096) | (0.609) | (0.111) | |
| Household size (no.) | −0.084 | 0.026∗∗∗ | −0.114∗ | 0.043∗∗∗ |
| (0.063) | (0.010) | (0.066) | (0.011) | |
| Dependents (%) | 0.000 | −0.001 | 0.002 | −0.001 |
| (0.005) | (0.001) | (0.005) | (0.001) | |
| Off-farm income (yes = 1) | −0.392∗∗ | 0.015 | −0.495∗∗∗ | 0.002 |
| (0.190) | (0.039) | (0.174) | (0.036) | |
| Ln asset ownership (USD) | 0.117∗ | 0.088∗∗∗ | 0.151∗∗ | 0.083∗∗∗ |
| (0.069) | (0.016) | (0.074) | (0.016) | |
| Ln land owned (ha) | 0.247 | 0.263∗∗∗ | 0.332 | 0.257∗∗∗ |
| (0.306) | (0.055) | (0.280) | (0.054) | |
| Ln distance to market (km) | −0.420 | 0.052 | −0.243 | 0.053 |
| (0.368) | (0.070) | (0.395) | (0.070) | |
| Average rainfall (mm) | 0.032∗∗ | 0.004 | 0.029∗∗ | 0.002 |
| (0.013) | (0.003) | (0.013) | (0.003) | |
| St. dev. of rainfall (mm) | 0.057∗∗∗ | 0.001 | 0.051∗∗∗ | −0.002 |
| (0.010) | (0.003) | (0.010) | (0.003) | |
| Black soil (yes = 1) | −0.137 | 0.020 | −0.633∗ | 0.059 |
| (0.353) | (0.073) | (0.377) | (0.074) | |
| Sandy soil (yes = 1) | −0.029 | −0.000 | 0.095 | −0.006 |
| (0.143) | (0.034) | (0.146) | (0.035) | |
| Mixed soil (yes = 1) | 0.151 | −0.025 | 0.261∗ | −0.025 |
| (0.125) | (0.035) | (0.138) | (0.033) | |
| Sigma | 0.281∗∗∗ | 0.279∗∗∗ | ||
| (0.012) | (0.012) | |||
| Observations | 1212 | 1212 | ||
| Households | 606 | 606 | ||
| Bootstrapping replications | 1000 | 1000 | ||
Note: The first double hurdle regression (column 1 and 2) treats technology transfer and access to seed as exogenous to the decision to adopt. The second double hurdle regression (column 3 and 4) includes first stage residuals to control for potential endogeneity of technology transfer and access to seed. Results from the first stage reduced form regression are presented in Appendix Table A. Fully robust bootstrapped standard errors in parentheses (*p < 0.10, **p < 0.05, ***p < 0.01). Regressions include the means of time-variant variables, year dummies and village dummies.
Adoption impact on income and poverty: fixed effects instrumental variable estimation.
| (1) | (2) | (3) | (4) | |
|---|---|---|---|---|
| Ln income per capita | Ln household income | Poor (<$1.25) | Poor (<$2.00) | |
| Ln improved chickpea area (ha) | 1.261∗∗ | 1.226∗∗ | −0.274 | −0.388∗ |
| (0.551) | (0.605) | (0.203) | (0.207) | |
| Male head (yes = 1) | 0.177 | 0.189 | −0.196∗∗ | 0.056 |
| (0.185) | (0.187) | (0.098) | (0.112) | |
| Household size (No.) | −0.113∗∗ | 0.058 | 0.064∗∗∗ | 0.087∗∗∗ |
| (0.045) | (0.051) | (0.012) | (0.013) | |
| Dependents (%) | −0.004 | −0.004 | 0.000 | 0.001 |
| (0.004) | (0.004) | (0.001) | (0.001) | |
| Off-farm income (yes = 1) | 0.208∗∗∗ | 0.211∗∗∗ | −0.069∗ | −0.067 |
| (0.068) | (0.069) | (0.038) | (0.042) | |
| Ln land owned (ha) | −0.019 | −0.079 | −0.293∗∗∗ | −0.241∗∗∗ |
| (0.285) | (0.328) | (0.066) | (0.070) | |
| Average rainfall (mm) | 0.001 | 0.004 | 0.003 | 0.005 |
| (0.008) | (0.009) | (0.003) | (0.003) | |
| St. dev. rainfall (mm) | 0.021∗ | 0.024∗ | −0.006∗∗ | −0.006∗∗ |
| (0.011) | (0.013) | (0.003) | (0.003) | |
| Kleibergen-Paap Wald F-statistic | 67.176∗∗ | 67.176∗∗ | 67.176∗∗ | 67.176∗∗ |
| Observations | 1212 | 1212 | 1212 | 1212 |
| Households | 606 | 606 | 606 | 606 |
| Bootstrapping replications | 1000 | 1000 | 1000 | 1000 |
Note: Columns present fixed effects instrumental variables regressions for four different measures of household welfare as the dependent variable. In all models Ln improved chickpea area is treated as endogenous and instrumented with the predicted improved chickpea area from the endogenous double hurdle model in column (4) of Table 4. Fully robust bootstrapped standard errors in parentheses (*p < 0.10, **p < 0.05, ***p < 0.01). In addition to household fixed effects, regressions include year dummies.
Robustness checks of adoption impact.
| (1) | (2) | (3) | (4) | |
|---|---|---|---|---|
| Ln income per capita | Ln household income | Poor (<$1.25) | Poor (<$2.00) | |
| (1) Primary results | 1.261∗∗ | 1.226∗∗ | −0.274 | −0.388∗ |
| (0.551) | (0.605) | (0.203) | (0.207) | |
| (2) Tech. transfer and seed access exogenous | 1.327∗∗ | 1.328∗ | −0.293 | −0.382∗ |
| (0.632) | (0.703) | (0.206) | (0.201) | |
| (3) 1% trim | 1.341∗∗ | 1.297∗∗ | −0.335∗ | −0.420∗∗ |
| (0.564) | (0.616) | (0.199) | (0.209) | |
| (4) Village time interactions | 1.305∗∗ | 1.293∗∗ | −0.361∗ | −0.440∗∗ |
| (0.568) | (0.620) | (0.215) | (0.211) | |
| (5) Ln improved chickpea seed (kg) | 0.073∗ | 0.069∗ | −0.027 | −0.038∗∗ |
| (0.039) | (0.042) | (0.018) | (0.019) | |
| (6) Two-stage Tobit | 2.088∗∗∗ | 2.077∗∗∗ | −0.603∗ | −0.456 |
| (0.742) | (0.799) | (0.333) | (0.338) | |
| Observations | 1212 | 1212 | 1212 | 1212 |
| Number of households | 606 | 606 | 606 | 606 |
Note: Columns present fixed effects instrumental variables regressions for four different measures of household welfare as the dependent variable. Row (1) reports, for purposes of comparison, the results found in Table 5. Row (2) reports results using the predicted improved chickpea area from the exogenous double hurdle model in column (2) of Table 4 as an instrument for observed values. Row (3) reports results from the balanced panel when we trim the top and bottom 1% of observations based on initial income per capita. Row (4) includes village specific time trends to control for village specific trends that may be correlated with chickpea adoption. Row (5) presents an alternative specification in which the extent of adoption is measured by the quantity of improved chickpea seeds planted. Row (6) reports results in which we replace the CF double hurdle with a more standard two-stage instrumented Tobit prior to our fixed effects regression. Fully robust bootstrapped standard errors in parentheses (*p < 0.10, **p < 0.05, ***p < 0.01). Regressions include explanatory variables from Table 5, household fixed effects and year dummies.
Fixed effects estimation: adoption impact by initial land ownership.
| (1) | (2) | |
|---|---|---|
| Ln income per capita | Ln household income | |
| Quartile 1 ∗ Ln improved chickpea area | 2.227∗∗∗ | 2.424∗∗∗ |
| (0.752) | (0.821) | |
| Quartile 2 ∗ Ln improved chickpea area | 1.269∗ | 1.335∗ |
| (0.732) | (0.809) | |
| Quartile 3 ∗ Ln improved chickpea area | 1.469∗∗ | 1.315∗ |
| (0.677) | (0.738) | |
| Quartile 4 ∗ Ln improved chickpea area | 0.180 | 0.109 |
| (1.193) | (1.306) | |
| Observations | 1212 | 1212 |
| Number of households | 606 | 606 |
Note: Columns present fixed effects instrumental variables regression results similar to those presented in Columns (1) and (2) of Table 5 except that the instrumented variable is interacted with an indicator for the initial land quartile to which each household belongs. Fully robust bootstrapped standard errors in parentheses (*p < 0.10, **p < 0.05, ***p < 0.01). Regressions include explanatory variables from Table 5, household fixed effects and year dummies.
Costs and benefits of chickpea production.
| Full sample | |||
|---|---|---|---|
| Non-adopter | Adopter | ||
| Chickpea area (ha) | 0.19 | 0.65 | ⁎⁎⁎ |
| Chickpea seed (USD/ha) | 183 | 261 | ⁎⁎⁎ |
| Chickpea fertilizer (USD/ha) | 11.4 | 19.2 | ⁎⁎ |
| Chickpea chemical (USD/ha) | 19.3 | 41.7 | ⁎⁎⁎ |
| Chickpea hired labour (USD/ha) | 24.2 | 46.1 | ⁎⁎⁎ |
| Chickpea family labour (days/ha) | 78.3 | 74.3 | |
| Chickpea yields (kg/ha) | 1875 | 2338 | ⁎⁎⁎ |
| Sold chickpeas (yes = 1) | 0.37 | 0.87 | ⁎⁎⁎ |
| Share of chickpea production sold (%) | 54.3 | 58.0 | ⁎ |
| Chickpea sales (kg) | 401 | 857 | ⁎⁎⁎ |
| Chickpea sales price (USD/kg) | 1.25 | 1.33 | ⁎⁎ |
| Net returns to chickpea sales (USD) | 739 | 1727 | ⁎⁎⁎ |
| Chickpea sales as share of income (%) | 21.6 | 38.6 | ⁎⁎⁎ |
| Observations | 369 | 1050 | |
Significance of t-tests are reported as ⁎p < 0.10; ⁎⁎p < 0.05; ⁎⁎⁎p < 0.01.
Correlated random effects probit model of access to technology transfer and seed.
| (1) | (2) | |
|---|---|---|
| Access technology transfer (yes = 1) | Buys improved seed (yes = 1) | |
| −1.488∗∗∗ | ||
| (0.542) | ||
| −0.891∗∗∗ | ||
| (0.267) | ||
| Age head (yrs) | −0.015∗∗∗ | −0.009∗∗ |
| (0.005) | (0.004) | |
| Education head (yrs) | −0.006 | 0.016 |
| (0.019) | (0.018) | |
| Male head (yes = 1) | −1.092∗∗ | 0.395 |
| (0.437) | (0.447) | |
| Household size (No.) | −0.144∗∗∗ | −0.012 |
| (0.043) | (0.046) | |
| Dependents (%) | 0.007∗ | −0.002 |
| (0.004) | (0.004) | |
| Off-farm income (yes = 1) | −0.149 | −0.090 |
| (0.152) | (0.134) | |
| Ln initial asset ownership (USD PPP) | 0.096∗ | 0.016 |
| (0.057) | (0.052) | |
| Ln land owned (ha) | 0.451∗ | −0.043 |
| (0.237) | (0.188) | |
| Ln market distance (min) | −0.015 | 0.228 |
| (0.294) | (0.238) | |
| Average rainfall (mm) | 0.013 | 0.006 |
| (0.010) | (0.011) | |
| Standard deviation rainfall (mm) | 0.006 | 0.005 |
| (0.010) | (0.009) | |
| Black soil (yes = 1) | −0.196 | −0.336∗ |
| (0.238) | (0.204) | |
| Sandy soil (yes = 1) | 0.056 | 0.086 |
| (0.128) | (0.106) | |
| Mixed soil (yes = 1) | 0.032 | 0.097 |
| (0.117) | (0.098) | |
| Observations | 1212 | 1212 |
| Households | 606 | 606 |
Note: Column (1) presents first stage regression results predicting access to technology transfer with lagged weighted distance to technology transfer as an instrument. Column (2) presents first stage regression results predicting access to improved seed with lagged weighted distance to seed as an instrument. Fully robust standard errors in parentheses (*p < 0.10, **p < 0.05, ***p < 0.01). Regressions include the means of time-variant variables, year dummies and village dummies.