Palm oil and poverty in Indonesia Ryan B. Edwards Arndt-Corden Department of Economics Crawford School of Public Policy ADEW, June 2015 ryan.edwards@anu.edu.au @ryanbedwards Question Oil palm land use Poverty Counterfactual example: oil palm vs. all over land use Does district d, which has converted land into oil palm plantations, currently have lower poverty than it would have if it had not converted the land? 2 Approach Nationwide district-level balanced panel (DAPOER) – No RCT or policy discontinuity for natural experiment – Exploit spatial and temporal variation Longitudinal features of the data allow me to control for: – Time-invariant district-specific confounders – Common nation-wide and regional shocks and policies – Different initial conditions and time trends Causal effect identified if no time and district-varying OVB 1. Theory and empirical exercises suggest unlikely 2. Consonant results from instrumental variable estimation Caveat: data not perfect and omitted variables cannot be ruled out 3 District poverty rate, 2002-2010 Share of population below expenditure-based poverty line Also look at poverty gap index, no. of poor (i.e., drop denominator) • Most poor people live on Java; rates highest periphery • 10 million people lifted from poverty in the decade under study 4 Official (declared) palm oil land / total district area Tree Crop Statistics; reflects policy settings (actual not available) • Land key policy issue; central to expansion (92%) • 2001-2009, 5 17 mill. ha (8.7%), mostly “smallholder” expansion • Reduced-form; heterogeneity contained with • Share focuses on changing composition (c.f., other uses) 5 Basic estimating equation District and period specific error term Heteroskedasticity robust District-clustered for serial correlation Lag District oil palm land / total district area land SUSENAS measured mid-year; need time to effect Not logged to retain the ‘control group’ Log poverty rate in district d in year t Natural logs for skewedness Semi-elasticity interpretation 6 Fixed effects and estimation District fixed effects (d=~330) Time invariant district specific factors Climate, geography, history, institutions Island-year fixed effects (i=5; t=9) Time and district varying factors shared across island Regional and national growth, shocks, cycles, policies Mean-differenced FE estimator Allows level effects Time-to-effect temporal dimension Long differences Remove time-invariant bias Island, initial pov.,palm, controls 7 Identification No time and district varying omitted variables correlated with changes in both poverty and palm oil land influential enough to systemically shift poverty trends within island groupings (i.e., conditional independence) 1. 2. 3. 4. Identifying variation fundamentally driven by bureaucracy Selection across & within arguably mostly captured by FEs Placebo tests using future values Coefficients stable to DAPOER district-specific controls and adding province-specific time trends (very-rich control vector) 5. Unobservable hetero can’t be ruled out in observational studies 8 Instrumental variables Panel LIML IV: 2000 district palm oil land*year • Focus on demonstration effects: – path-dependence from initial-conditions – pre-existing knowledge, materials, supply chains • Main drawback: LATE omits “new” palm oil districts Long-difference LIML IV • 2000 palm oil land as above • Rainfall Better in humid low land tropics • Slope Less mountainous better for plantation Significant < 0.1% in first-stage All three violate exclusion restriction in theory 9 No relationship between IVs and poverty reduction in “non-treated” districts. Cannot rule out a relationship in treated districts. Bonus: if an instrument is valid, over-identification tests are no longer useless (informative on lag land) 10 Main result: Effect of palm oil land on district poverty Annual Sample Estimator FE LIML Two yearly Four yearly FE FE LIML LIML Long difference FE LIML Impact on poverty (coefficient, semi-elasticity) 0 -0.01 -0.02 -0.03 -0.04 -0.05 -0.06 -0.07 11 Heterogeneity, by sub-sector State-owned land Sample Annual Two yearly Four yearly Baseline district and year FE model (no IV) Long-diff not available; Private owned (company) land Annual Two yearly Four yearly Smallholder land Annual Two yearly Four yearly Impact on poverty (coefficient, semi-elasticity) 0 -0.005 -0.01 -0.015 -0.02 12 Answer to question Districts which have increased oil palm land have experienced greater reductions in the poverty rate and the depth of poverty • Effect increases from 1-4 years • Evident a decade later • Relatively consistent across regions and sectors • No evidence of local short-run economic spillovers (not presented) 13 Main limitations • Cannot generalise beyond average within-district effect • Long-shot analysis: mechanisms, spill-overs, GE effects unclear • Endogeneity still a problem; declared vs. actual Ongoing improvements to the paper • Strengthen identification strategy (OVB bounds; controls) • Reconcile with SUSENAS (distributional analysis) • Look into mechanisms further (labour demand, logging income, role of productivity, spill-overs and other sectors) • More detailed regional analysis 14
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