Fig. 1.
Diagnostic and reliability test results
| Diagnostic test | Test approach | Test statistics | Prob. value |
|---|---|---|---|
| Normality | Jarque-Bera test | 0.458 | 0.418 |
| Serial correlation | Breusch-Godfrey LM test | 2.153 | 0.272 |
| Heteroskedasticity | Breusch-Pagan-Godfrey test | 0.542 | 0.671 |
| Functional form | Ramsey reset test | 0.231 | 0.141 |
| Wald short run | Wald test | 6.131 | 0.012 |
| Wald long run | Wald test | 7.012 | 0.001 |
| Stability test | CUSUM test | Stable | |
| Stability test | CUSUMQ test | Stable |
Description of dependent and independent variables
| Variable | Description | Notation |
|---|---|---|
| Labour productivity | Dividing total agricultural output by the number of workers engaged in agricultural activities | LABP |
| Government expenditure | The amount of money a government spends on the agricultural sector | GEXP |
| Commercial banks’ credit | Amount of credit to farmers | CBCR |
| Microfinance banks’ loans | Amount of loans accessed by farmers | MFBL |
| Agricultural credit guarantee scheme funds | Sum of money accessed by farmers through the agricultural credit guarantee scheme | ACGSF |
| Number of deaths | The total number of deaths due to insecurity | DTHS |
Unit root test results
| Variables | ADF test with intercept and trend | PP test with intercept and trend | ||||
|---|---|---|---|---|---|---|
| level | 1st difference | I (d) | level | 1st difference | I(d) | |
| LnLABP | –0.759 | –5.086*** | I(1) | –0.840 | –5.082*** | I(1) |
| LnGEXP | –4.284** | –6.051*** | I(0) | –4.270** | –8.908*** | I(0) |
| LnCBCR | –3.669** | –6.195*** | I(0) | –3.673** | –7.147*** | I(0) |
| LnMFBL | –3.605** | –5.420*** | I(0) | –4.739** | –9.882*** | I(0) |
| LnACGS | –0.808 | –3.765*** | I(1) | –1.045 | –3.801** | I(1) |
| LnDTHS | –2.178 | –6.861*** | I(1) | –2.096 | –7.144*** | I(1) |
Zivot and Andrews unit root structural break test
| Variables | Level | First difference | ||
|---|---|---|---|---|
| t-Statistics | time break | t-Statistics | time break | |
| LnLABP | –7.013** | 2016 | –9.181** | 2020 |
| LnGEXP | –2.021 | 1993 | –7.427** | 2015 |
| LnCBCR | –0.801 | 2008 | –9.021** | 2016 |
| LnMFBL | –1.001 | 2004 | –6.219** | 2005 |
| LnACGS | –4.027** | 1998 | –5.728** | 2001 |
| LnDTHS | –4.321** | 2013 | –4.921** | 2019 |
Descriptive statistics
| LnLABP | LnGEXP | LnCBCR | LnMFBL | LnACGS | LnDTHS | |
|---|---|---|---|---|---|---|
| Mean | 29.879 | 9.669 | 11.760 | 7.801 | 7.603 | 10.316 |
| Median | 30.060 | 10.320 | 11.665 | 8.355 | 8.365 | 9.665 |
| Maximum | 30.590 | 11.310 | 14.330 | 10.050 | 9.470 | 13.920 |
| Minimum | 28.930 | 6.120 | 8.850 | 3.380 | 4.390 | 7.870 |
| Std. Dev. | 0.600 | 1.487 | 1.533 | 1.855 | 1.702 | 2.328 |
| Skewness | –0.413 | –0.800 | 0.054 | –0.626 | –0.699 | 0.422 |
| Kurtosis | 1.595 | 2.422 | 1.902 | 2.356 | 1.924 | 1.536 |
| Jarque-Bera | 3.543 | 3.863 | 1.623 | 2.648 | 4.151 | 3.806 |
| Probability | 0.170 | 0.144 | 0.444 | 0.266 | 0.125 | 0.149 |
| Observations | 32 | 32 | 32 | 32 | 32 | 32 |
Bounds test co-integration test result
| F-bounds Test | Null hypothesis: No levels relationship | |||
|---|---|---|---|---|
| Test statistic | Value | Signif. | I(0) | I(1) |
| F-statistic | 13.798 | 10% | 2.080 | 3.000 |
| k | 5 | 5% | 2.390 | 3.380 |
| 1% | 3.060 | 4.150 | ||
Estimated long-run results
| Variable | Coefficient | Std. Error | t-Statistic | Prob. |
|---|---|---|---|---|
| LnGEXP+ | 0.258 | 0.064 | 4.031 | 0.001*** |
| LnGEXP– | –0.391 | 0.129 | –3.031 | 0.009*** |
| LnCBCR+ | 0.410 | 0.102 | 4.020 | 0.002*** |
| LnCBCR– | –0.183 | 0.082 | –2.243 | 0.042*** |
| LnMFBL+ | 0.175 | 0.742 | 2.351 | 0.041** |
| LnMFBL– | –0.176 | 0.039 | –2.722 | 0.022** |
| LnACGS+ | 0.157 | 0.058 | 2.679 | 0.013** |
| LnACGS– | –0.278 | 0.097 | –2.866 | 0.017** |
| LnDTHS+ | –0.521 | 0.158 | –3.299 | 0.008*** |
| LnDTHS– | 0.609 | 0.179 | 3.392 | 0.003*** |
| Constant | 0.762 | 0.330 | 2.309 | 0.040** |
Estimated short-run results using the NARDL
| Variable | Coefficient | Std. Error | t-Statistic | Prob. |
|---|---|---|---|---|
| D(LnGEXP) | 0.118 | 0.016 | 7.213 | 0.000*** |
| D(LnGEXP(-1)) | –0.244 | 0.025 | –9.760 | 0.000*** |
| D(LnGEXP(-2)) | –0.137 | 0.045 | –3.044 | 0.003*** |
| D(LnGEXP(-3)) | 0.108 | 0.016 | 6.692 | 0.000*** |
| D(LnCBCR) | –0.286 | 0.046 | –6.217 | 0.000*** |
| D(LnCBCR(-1)) | 0.098 | 0.044 | 2.210 | 0.046** |
| D(LnMFBL) | –0.046 | 0.017 | –2.634 | 0.021** |
| LNMFBL(-1) | 0.122 | 0.014 | 8.714 | 0.000*** |
| D(LNACGS) | 0.217 | 0.094 | 2.294 | 0.031** |
| D(LNACGS(-1)) | 0.147 | 0.065 | 2.261 | 0.041** |
| D(LNACGS(-2)) | –0.212 | 0.073 | –2.927 | 0.012** |
| D(LNACGS(-3)) | 0.136 | 0.054 | 2.519 | 0.026** |
| D(LNDTHS) | –0.136 | 0.058 | –2.356 | 0.026** |
| D(LNDTHS(-1)) | 0.380 | 0.149 | 2.546 | 0.024** |
| ECM(-1) | –0.200 | 0.022 | –9.111 | 0.000*** |
| R-squared | 0.889 | |||
| Adjusted R-squared | 0.837 | |||
| F-statistic | 45.013 | |||
| Prob(F-statistic) | 0.000 | |||
| Durbin-Watson stat | 2.292 |