J10 | Macro Paper Warehouse

Civil War–Induced Displacement and Human Capital

Mon, 01 Jan 0001 00:00:00 +0000

This paper examines the impact of conflict-driven forced displacement on human capital accumulation using the Mozambican civil war (1977–1992) as the empirical setting. During this war, over four million civilians — roughly a third of the population — fled to rural areas, cities, neighboring countries, or UN-managed refugee camps. The study advances on prior work in three dimensions: it uses the full post-war population census (12 million individuals) rather than a small survey; it studies multiple displacement trajectories in a single framework; and it separately identifies place-based exposure effects from a general uprootedness effect.

The primary data source is the 1997 Mozambican census, which records each individual’s place of birth, residence in 1992 (the war’s end), and residence in 1997. Key outcomes are educational attainment and sectoral employment (agricultural versus services). The authors supplement the census with digitized colonial road and school maps, georeferenced conflict events, and landmine contamination data.

The main identification strategy compares approximately 135,000 siblings (from 45,000 families) separated during the war, using the sibling who stayed behind as a within-family counterfactual. This design controls for household-level characteristics including religious and ethnic background, aspirations, and exposure to violence.

The key findings are as follows. First, rural-born IDPs displaced to cities have a 7.3 percentage point higher likelihood of attending primary school and 0.53 more years of schooling compared to their siblings who stayed behind — roughly one-third of the non-displaced mean. Rural-born IDPs displaced to other rural areas also show gains, with a 3 percentage point higher likelihood of attending school and 0.24 additional years, supporting the uprootedness hypothesis even for displacements that did not reach urban centers. Urban-born IDPs forcibly relocated to the countryside — primarily through FRELIMO’s villagization scheme — experienced 9 percentage point lower primary school attendance and approximately 0.5 fewer years of schooling relative to siblings who remained in cities.

External displacement (to camps in Malawi or Zimbabwe) generated no significant schooling gains relative to staying siblings, despite UN-built schools in camps, likely because scarce employment opportunities reduced perceived returns to education.

Second, the paper jointly estimates place-based and uprootedness effects in a single within-family framework. Place effects are statistically significant: displacement to a district one standard deviation more developed than one’s birthplace raises schooling likelihood by approximately 3 percentage points (OLS) to 5 percentage points (2SLS reduced form). Crucially, a residual uprootedness effect of approximately 2–4 percentage points persists even after controlling fully for destination-origin differences in development and conflict intensity. This uprootedness effect is quantitatively comparable to being displaced to a district one standard deviation more developed than one’s birthplace.

Third, a primary survey of 208 Nampula residents conducted in early 2020 — three decades after the war — confirms lasting educational gains. IDPs displaced to Nampula have a 10 percentage point higher likelihood of completing primary school relative to their siblings who stayed in the countryside, and their educational attainment converged to levels of urban-born, never-displaced residents despite large urban-rural education gaps. However, IDPs report significantly lower social capital, civic participation, and community trust than urban-born respondents, and score significantly worse on mental health indicators, including depression, loneliness, and pessimism. These psychosocial costs persist three decades after the war’s end.

The findings apply to a low-income, post-colonial African setting characterized by widespread illiteracy (over 60%) and subsistence agriculture (over 85% of employment) at the war’s close. The results are robust to alternative age restrictions, extended family comparisons, dropping the oldest sibling, same-sex sibling pairs, and narrowing the age gap between sibling pairs to as few as two years.

Q: What is the core identification strategy and why is it preferred over cross-sectional estimates? A: The authors compare siblings within the same household who experienced different displacement trajectories during the war. Because siblings share household-level characteristics — parental preferences for education, ethnic and religious background, wealth, and local conflict exposure — the within-family design controls for confounders that would bias cross-sectional estimates. The within-family estimates are systematically smaller than cross-sectional ones (e.g., 7.3 pps vs. 24–30 pps for rural-to-urban displacement in primary school attendance), confirming that sorting was present even in the unpredictable civil war setting.

Q: What do the results show for rural-born IDPs displaced to urban centers? A: Within the sibling-pair framework, rural-born IDPs displaced to cities and towns have a 7.3 percentage point higher likelihood of attending primary school and 0.53 more years of schooling compared to their siblings who stayed in rural birthplaces, against a non-displaced sibling mean of approximately 20% primary school access and one year of formal schooling. These IDPs also show a 4 percentage point higher likelihood of non-agricultural employment five years after the war’s end.

Q: What do the results show for rural-born IDPs displaced to other rural areas? A: Even displacement to a different rural district — not a city — generates modest but statistically significant gains: a 3 percentage point higher likelihood of attending school and 0.24 additional years of schooling relative to siblings staying in their birthplace rural district. The authors interpret this as evidence for the uprootedness hypothesis, since rural Mozambique at the time was among the most impoverished and insecure environments in the world, meaning destination quality alone cannot explain the gain.

Q: What do the results show for externally displaced refugees? A: Refugees displaced to camps and settlements in Malawi, Zimbabwe, Tanzania, Zambia, and Swaziland show schooling levels statistically similar to their siblings who remained in their rural birthplaces, despite UN-built primary schools in camps. The authors attribute the absence of gains to low perceived returns to education stemming from scarce employment opportunities at displacement destinations. Externally displaced individuals do show a 5 percentage point lower likelihood of agricultural employment relative to staying siblings.

Q: What are the consequences of urban-to-rural forced displacement? A: Urban-born individuals forcibly relocated to the countryside — primarily through FRELIMO’s villagization and food production programs — have approximately 9 percentage point lower likelihood of attending primary school and 0.5 fewer years of schooling compared to siblings who remained in urban areas. These results indicate that FRELIMO’s coercive relocation policies imposed material human capital costs on the displaced.

Q: How are place-based and uprootedness effects separated empirically? A: The authors construct principal component indices for destination-origin differences in regional development (aggregating population density, Portuguese-speaking share, offspring mortality, road density, colonial market density, and school density) and conflict intensity (conflict events per capita and landmine contamination per capita). They then include these continuous exposure measures alongside a binary displacement indicator in within-family regressions. The coefficient on the binary displacement indicator — conditional on destination-origin development and conflict differences — isolates the uprootedness effect for individuals displaced to districts with identical characteristics to their birthplace.

Q: What are the magnitudes of the place-based and uprootedness effects? A: Under OLS, displacement to a district one standard deviation more developed than one’s birthplace raises schooling likelihood by approximately 3 percentage points. The residual uprootedness effect — displacement per se, controlling for destination quality — raises schooling likelihood by approximately 2 percentage points. Under 2SLS (instrumenting destination-origin development differences with the development of districts within 100 km of birthplace), the place-based effect rises to approximately 5 percentage points in the reduced form, and the uprootedness effect remains significant at approximately 4 percentage points. Both the uprootedness and place-based effects are of comparable magnitude.

Q: What instrument is used in the 2SLS specifications and what is its first-stage strength? A: The instrument exploits the fact that Mozambique’s heavily mined and rudimentary transportation network constrained civilian movement — the median displaced sibling ended up roughly 97 kilometers from birthplace. The authors instrument actual destination-origin development and conflict differences with the predicted differences based on the characteristics of districts within 100 km of the birthplace. The first-stage elasticity between actual and proximity-predicted differences in development is 0.86, and for conflict is 0.88, both precisely estimated.

Q: What do the long-run survey results from Nampula show about educational persistence? A: In a 2020 survey of 208 Nampula residents aged over 35, IDPs who fled to Nampula during the war have a 10 percentage point higher likelihood of completing primary school relative to their siblings who stayed in the countryside. Their educational attainment converges to the level of urban-born, never-displaced Nampula residents, despite large historical and contemporary urban-rural education gaps in northern Mozambique. The majority of IDPs (73%) report that extended relatives or friends advised them to attend school upon arriving in the city, and most believed education was necessary for urban employment.

Q: What are the long-run psychosocial costs documented in the Nampula survey? A: Even three decades after the war’s end, IDPs in Nampula report significantly lower social capital, civic participation, and community trust compared to urban-born never-displaced residents. IDPs also score significantly worse on mental health indicators including depression, loneliness, and pessimism. These findings suggest that forced displacement imposes persistent psychosocial costs that are not remediated by economic or educational convergence.

Q: What drives displacement in the data, and does selection threaten identification? A: Linear probability and multinomial logit models show that conflict intensity and geographic proximity (distance to the border for external displacement; distance to cities for urban displacement) are the primary correlates of displacement type, while differences in destination development are uncorrelated with displacement. Nevertheless, the overall explanatory power of these models is low, confirming many idiosyncratic and unpredictable features of the war. The within-family design addresses residual selection on household characteristics, and the 2SLS design addresses selection on destination-specific characteristics.

Q: How do educational gains translate into sectoral employment outcomes? A: Across specifications, gains in schooling move in tandem with a shift out of agriculture into services. Rural-to-urban IDPs have a 4 percentage point higher likelihood of non-agricultural employment five years after the war, while externally displaced show a 5 percentage point lower likelihood of agricultural employment. Urban-born IDPs displaced to the countryside are more likely to work in agriculture after the war. The authors interpret this co-movement as suggesting that conflict-driven human capital accumulation may contribute to structural transformation away from subsistence agriculture.

Q: How robust are the within-family estimates? A: The authors conduct six sensitivity checks: adding family fixed effects to cross-sectional regressions, restricting to individuals aged 12–18 in 1997 to address co-habitation concerns, extending comparisons to cousins and other relatives, dropping the oldest male sibling to minimize favoritism concerns, restricting to same-sex sibling pairs, and narrowing the age gap to two years. Across all permutations, the qualitative ordering is preserved: refugees show no significant schooling gains, rural-to-urban IDPs show gains of 5–6 percentage points in primary attendance and 0.35–0.5 extra years, rural-to-rural IDPs show small positive gains, and urban-to-rural IDPs show losses.

Uprootedness hypothesis: The idea, traced in the paper to Stigler and Becker (1977) and earlier scholars, that forced displacement incentivizes human capital investment precisely because education is a mobile asset that cannot be expropriated — distinct from place-based effects of destination quality.

Place-based (exposure) effects: The impact on human capital outcomes attributable to differences between the development level and conflict intensity of the displacement destination and the individual’s birthplace, measured as destination-origin differences in a principal component index of regional development.

Separated siblings design: An identification strategy that compares siblings from the same household who experienced different displacement trajectories during the war, holding constant all household-level characteristics including parental preferences, ethnicity, religion, wealth, and local conflict exposure.

Internal displacement (IDP): Conflict-driven movement within national borders to either rural areas or urban centers, constituting approximately 60% of global forced displacement and the majority of displacement in the Mozambican civil war context.

Source text origin: A categorization of the working paper text used for summarization — distinguishing full PDF or HTML text from abstract-only text. Abstract-only text is a hard block for summary generation in the pipeline.

Structural transformation: In this paper’s usage, the shift of workers out of subsistence agriculture into services associated with human capital accumulation triggered by conflict-driven displacement, treated as a potential mechanism of post-conflict recovery.

Psychosocial costs of displacement: Long-run deficits in social capital, civic engagement, community trust, and mental health (depression, loneliness, pessimism) reported by IDPs three decades after displacement, persisting despite convergence in educational attainment and employment.

Revolutionary Transition: Inheritance Change and Fertility Decline

Mon, 01 Jan 0001 00:00:00 +0000

Gay, Gobbi, and Goñi test Le Play’s (1875) hypothesis that the French Revolution contributed to France’s early fertility decline by abolishing impartible inheritance. In 1793, a series of decrees culminating in the Loi de Nivôse (January 6, 1794) abolished testamentary rights and imposed equal partition of assets among all children — partible inheritance — across France, overriding the mosaic of local customs and written laws that had governed inheritance in the Ancien Régime.

The paper’s central argument is that this reform reduced the economic incentive to have children through indivisibility constraints in agricultural land. Under impartible inheritance, land passed to a single heir undivided, keeping plots above the subsistence productivity threshold even at high fertility. Under partible inheritance, each additional child fragments the land further, potentially pushing plots below the minimum productive size, so households face a strong incentive to limit fertility. A Stone-Geary production function with a minimum land threshold L̄ formalizes this mechanism: when landholdings fall in the binding range (L̄ < L < L̃), fertility is strictly higher under impartible than under partible inheritance.

The authors construct the first complete map of inheritance rules across France’s 435 judicial districts as of 1789, classifying each along two dimensions: partible versus impartible, and whether women were included or excluded. This atlas draws on Brette’s (1904) Atlas des Bailliages and the Nouveau Coutumier Général (Bourdot de Richebourg 1724), covering 141 distinct customs. Treatment is defined as municipalities under impartible inheritance before 1793 whose system was altered by the reforms; control municipalities were already under partible inheritance.

The main identification strategy is a difference-in-differences (DD) design comparing women with varying lengths of remaining fertile years after 1793 — from 0 for women aged 40+ at the reform to 25 for women aged 15 or younger — across treated and untreated municipalities. This is augmented by a regression-discontinuity difference-in-differences (RD-DD) design exploiting sharp discontinuities at judicial district borders. Two independent datasets are used: the Enquête Louis Henry (34,812 women in 39 rural municipalities, family-reconstitution method) and Geni.com crowdsourced genealogies (11,649 women across 2,966 locations after the Blanc 2023 horizontal restriction).

Each additional fertile year of exposure to the 1793 reforms reduced completed fertility by approximately 1 percent. Over the full 25-year fertile cycle, this corresponds to a reduction of roughly 0.7 children, or 24 percent relative to the pre-reform mean of 2.92 surviving children in treated areas. This magnitude equals the entire pre-reform fertility gap between impartible- and partible-inheritance areas (2.9 versus 2.2 children), meaning the reforms closed this gap entirely. DD and RD-DD estimates are similar and not statistically distinguishable from each other, and results replicate across both datasets. Results hold on both the extensive margin (childlessness) and intensive margin (fertility of mothers).

The mechanism is most relevant where smallholder landownership is widespread. France — where 40–80 percent of households owned land at the eve of the Revolution — meets this condition. England and Prussia, with more concentrated landownership, would not be expected to show the same response because the indivisibility constraint would not bind even after partition.

Q: What was France’s inheritance system before the Revolution, and how heterogeneous was it? A: Before 1793, inheritance was governed by 141 distinct customary and written laws applied within 435 judicial districts. The country was broadly divided between the customary-law north (Pays de droit coutumier) and the Roman written-law south (Pays de droit écrit), with substantial local variation within regions. Systems ranged from strictly partible (equal division among all offspring) to impartible (primogeniture, ultimogeniture, or unigeniture). Systems also varied in whether women could inherit or received only a dowry. This geographic variation — rooted in the laws of Germanic peoples after the fall of Rome in 476 CE — is exogenous to late eighteenth-century economic conditions and provides the identifying variation for the paper.

Q: What exactly did the 1793 reforms change, and were they enforced? A: The Loi de Nivôse an II (January 6, 1794) abolished testamentary rights entirely and mandated equal partition of assets among all children, including women, throughout France. The reforms came unexpectedly — only 8 of 571 cahiers de doléances analyzed by Goy (1988) mentioned inheritance — and were motivated by the equality principle, legal unification, and the fear that revolutionary sympathizers would be disinherited (Lataste et al. 1901). Offspring quickly asserted their new rights, and by the late 1790s inheritance disputes were the most common cases before family tribunals (Desan 1997; Poumarède 2011).

Q: What is the model’s core mechanism linking inheritance reform to fertility decline? A: The model uses a Stone-Geary production function with a minimum land threshold L̄ below which output falls to zero. Under impartible inheritance, land passes undivided to a single heir, keeping the farm above L̄ regardless of family size. Under partible inheritance, each child receives an equal share, so adding children risks fragmenting plots below L̄ — a powerful incentive to limit family size. The fertility gap between impartible and partible households is at its maximum when landholdings fall in the intermediate range (L̄ < L < L̃) where the constraint is binding. As land size increases, the constraint becomes less binding but the positive fertility differential persists.

Q: What is the paper’s main quantitative estimate of the reform’s effect on completed fertility? A: Each additional fertile year of exposure to the 1793 reforms reduced completed fertility by approximately 1 percent. Over the full 25-year fertile cycle (ages 15–40), this implies a reduction of roughly 0.7 children, or 24 percent relative to the pre-reform mean of 2.92 surviving children in treated areas. This is nearly identical to the pre-existing fertility gap between impartible- and partible-inheritance areas (0.7 children: 2.9 versus 2.2 surviving children), implying the reforms effectively eliminated the fertility differential.

Q: Are the DD and RD-DD estimates consistent with each other, and do both datasets agree? A: Yes. The DD and RD-DD estimates are similar and not statistically different from each other. The RD-DD design compares women born close to judicial district borders where inheritance rules differed, before and after 1793, exploiting the sharp spatial discontinuity at those borders. Consistency across these two designs — which rely on different identifying assumptions — strengthens causal interpretation. Results are also consistent across the Enquête Louis Henry (family-reconstitution) and Geni.com (crowdsourced genealogies) datasets, which are produced by fundamentally different methodologies.

Q: How do the authors verify the parallel trends assumption? A: Figure 6 shows that for cohorts who completed their fertile cycle before 1793, fertility trended downward in parallel across partible- and impartible-inheritance areas: a constant gap of approximately 0.7 children was maintained from women born in the early 1700s (3 versus 2.3 children) through women born in the early 1750s (2.7 versus 2.0 children), the last cohorts to complete fertility before the reforms. The convergence — from 0.7 to 0 children — only begins among cohorts fertile after 1793. The authors also include flexible trend controls interacted with municipality-level religiosity, political support for the Revolution, proximity to administrative centers, and wheat prices, and confirm the main estimate is robust.

Q: What role did the extension of inheritance rights to women play? A: The extension of rights to women was a companion mechanism distinct from abolishing impartible inheritance. Beyond increasing the number of heirs (which directly reduces land per heir), the right to inherit improves a woman’s outside option and postpones entry into marriage, following de Moor and van Zanden (2010). The DD and RD-DD estimates suggest that including women in inheritance and abolishing impartible inheritance had similar effects on fertility. The paper treats these as separate but reinforcing channels.

Q: How do the authors address potential confounders — mortality, migration, and economic conditions? A: On mortality: child mortality did not evolve differently after 1793 across areas with different inheritance rules (Appendix Table A3), and baseline adult mortality (age at death, probability of dying before completing the fertile cycle) was balanced across treated and control areas (Table 1). On migration: the authors explicitly rule out that results are driven by migration. On economic conditions: municipality-specific decade-average wheat prices (Ridolfi 2019) are included as controls for local Malthusian dynamics, and results are robust to their inclusion.

Q: What do the balance tests show? A: Panel A of Table 1 shows that before the reforms, areas with impartible versus partible inheritance were balanced on 9 of 11 individual-level characteristics — including husband and wife age at death, probability of dying before completing the fertile cycle, probability that parents-in-law were alive at marriage, literacy, data accuracy, and age at marriage. The only systematic pre-reform difference was fertility itself (0.7 children). Municipality-level climatic variables, soil suitability, and proxies for mortality uncertainty were also balanced. This is consistent with the origins of these systems in post-Roman Germanic law, which are unrelated to late eighteenth-century economic conditions.

Q: What robustness checks are reported? A: The authors report: (1) permutation tests reshuffling treatment exposure across women and municipalities; (2) non-linear treatment effects across cohorts, showing the heterogeneity required to explain away the baseline estimate is implausibly large per de Chaisemartin and d’Haultfoeuille (2020); (3) exclusion of outlier municipalities; (4) a placebo test for cohorts who completed their fertile cycle before 1793; (5) robustness to alternative sample definitions, treatment definitions, outcome variables, and control groups; (6) Cummins (2020) first-name repetition technique to correct for under-reported child deaths in Henry; (7) terrain characteristics including climatic and soil suitability (Galor and Özak 2016) and ruggedness (Nunn and Puga 2012); (8) for RD-DD: alternative bandwidths, running variable specifications, kernel functions, samples, and border-segment fixed effects. All checks support the main finding.

Q: Why did France experience a fertility decline from inheritance reform while other countries with similar reforms did not? A: The model rationalizes this through landownership structure. The fertility-reducing mechanism operates through indivisibility constraints that bind only when landholdings are small and fragmented — as in France, where 40–80 percent of households owned their land and plots were small. Where landownership is concentrated (England, Prussia), land per heir remains above L̄ even after partible division, so the indivisibility constraint is non-binding and fertility is unaffected by the reform. This provides a structural reason why France’s particular agrarian structure made it uniquely susceptible to this mechanism.

Q: What is the broader historical significance for understanding France’s early demographic transition? A: France’s fertility decline began roughly 50 years before industrialization, making it anomalous relative to standard quantity-quality tradeoff theories linking fertility decline to technological progress and rising returns to human capital. The 1793 reforms provide a legal-institutional explanation for the sharp post-Revolution acceleration visible in Figure 1, which is difficult to attribute to slowly-evolving cultural factors or human capital considerations not yet operative. The estimates imply the reforms brought large impartible-inheritance areas to the low-fertility regime that already characterized partible-inheritance areas, thus sharply accelerating the national transition.

Impartible inheritance: A system under which parents could designate a single heir (through primogeniture, ultimogeniture, or unigeniture) to receive the bulk of the family estate, preventing fragmentation of wealth; in pre-revolutionary France this was associated with extended family households and higher fertility (2.9 surviving children on average) relative to partible areas (2.2).

Partible inheritance: A system under which family wealth was divided equally among all offspring upon death; in the paper’s model this creates an incentive to limit fertility to prevent land fragmentation below the subsistence productivity threshold L̄.

Indivisibility constraint (land threshold L̄): In the Stone-Geary production function, a minimum land input below which agricultural output falls to zero; this is the mechanism through which partible inheritance generates fertility-limiting incentives, since dividing a small plot among many heirs risks crossing L̄ into zero production.

Difference-in-differences (DD) exposure design: The paper’s main identification strategy, using remaining fertile years after 1793 as a continuous treatment-intensity variable (0 for cohorts past fertility at the reform date, up to 25 for cohorts entirely within their fertile years), compared between treated municipalities (impartible → partible) and control municipalities (already partible).

Regression-discontinuity difference-in-differences (RD-DD): An augmented design exploiting the sharp geographic discontinuity at borders between judicial districts with different pre-reform inheritance rules, comparing outcomes on both sides before and after 1793, to address smooth unobserved confounders.

Completed fertility (net): The number of children surviving to age six, preferred over total births because child mortality before 1800 was high (1–1.5 children per mother did not survive to age six per Houdaille 1984), making net fertility the more economically meaningful measure for inheritance and bequest decisions.

Horizontal restriction: A sampling correction applied to crowdsourced genealogical data (Blanc 2023a) that retains an observation only if at least one of the four preceding generations has more than one recorded offspring, correcting for the over-representation of single-child families that arises because Geni users tend to record direct ancestors rather than collateral relatives.