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Targeting rural development interventions : empirical agent-based modeling in Nigerien villages

International audienceThe aim of this article is to analyze the impact of development interventions on the population of three Nigerien villages that differ in terms of their agro-ecological, social and economic characteristics. This is performed by simulating the behavior of individuals in an agent-based modeling framework which integrates the village characteristics as well as the family internal rules that condition access to economic and production activities. Villagers are differentiated according to the social and agro-ecological constraints they are subjected to. Two development project interventions are simulated, assuming no land scarcity: increasing the availability of inorganic fertilizers for farmers and an inventory credit technique based on millet grain. Two distinct approaches were used to model the rationale of farmers' decision making: gains or losses in economic value or gains or losses in within-village ''reputation''. Our results show that village populations do not respond en masse to development interventions. Reputation has little effect on the population behavior and should be considered more as a local proxy for wealth amongst villagers, suggesting the monetization of these societies. Populations involve themselves in the two simulated development interventions only at sites where savings are possible. Some level of household food security and investment capacity is actually required to take part in the development interventions, which are largely conditioned by family manpower and size. As long as uncultivated land remains available in the village territory, support for inorganic fertilizers has little impact in the absence of any intensification process. Inventory credit engages a maximum of 25% of the population at the site with medium agro-ecological conditions. Therefore, both interventions should be viewed as a potential support tool for a limited part of the population capable of going beyond the survival level, but not as a generic poverty-alleviation panacea

Benchmarking humanitarian support : empirical agent-based modeling of development action types in Nigerian villages

International audienceThe purpose of this article is to simulate and analyze the impacts of development interventions on the population of three different sites in Sahelian millet-cropping Niger (Sahelian Africa), taking account the differentiation of social and agro-ecological constraints on the different types of villagers. The work is based on a previous article (Saqalli, 2006), which has shown that using an individual Agent-based model (ABM) is a relevant approach to integrate agro-ecological, social and economic characteristics of a system and that family internal rules have strong impacts on village and environment evolutions. Two development project interventions are simulated in a context of no land scarcity: inorganic fertilizers availability for farmers and an inventory credit technique based on millet yields that some villagers may choose to use. Two rationalities are tested, one upon economic values and the second upon the intra-village "reputation" gains. Our results illustrate that a village cannot be considered as a whole and project operators must take in account the precise target population rather than all adult villagers. Project involvements concern only sites where savings for securization or intensification are possible: These proposals need actually some food security and investment capacities that are largely conditioned by family manpower and size. Inorganic fertilizers have little success without any intensification process in a context of good land availability. Inventory credit intervention engages a maximum of 25% of the population in the site with medium agro-ecological conditions. Reputation has little effect on the population behavior and should be considered more as a local wealth estimation factor between villagers. Therefore, one should consider these proposals as a potential support tool for a limited part of the population capable to go beyond the survival level,but not as a global poverty-alleviation panacea

Testing Social-driven Forces on the Evolution of Sahelian Rural Systems: A Combined Agent-based Modeling and Anthropological Approach

International audienceThis article presents the results of a methodology combining an extensive fieldwork, a formalization of field-based individual rules and norms into an agent-based model and the implementation of scenarios analyzing the effects of social and agro-ecological constraints on rural farmers through the study of three different sites in Nigerien Sahel. Two family transition processes are here tested, following field observations and literature-based hypotheses: family organizations can evolve between a patriarchal mode and a non-cooperative one because of family income redistribution tensions. Family inheritance systems can shift between a "customary" mode and a "local Muslim" one through family land availability tensions. Our results show that both agro-ecological and socio-economic characteristics determine the simulated family type distribution and consequently the allocation of resources. Results from simulations with no evolution processes show that villages specialize themselves on different economic activities according to natural resources: An intensification gradient is observed from the most favored site, with more local productions and improved ecological indicators, to the less-favored one, with a growing proportion of the population wealth coming from migration remittances and "off-shore" livestock. Once introducing such processes, the differentiation also occurs within the population level, subdividing it into specializing groups according to their size, their assets and their social status. Emerging individualistic family types increase the village populations' robustness through different and site-specific evolutions

Reconstituting family transitions of Sahelian western Niger 1950-2000 : an agent-based modelling approach in a low data context

International audienceThis research analyses the impacts of the family organization on the diversity of income sources and the sustainability and the dynamics of rainfed farming systems of Sahelian Niger, through an individual-centred agent-based model which variables were defined through anthropological investigation. Results show that family organisation has strong effects on wealth levels and distribution and on demographic growth. They also suggest a historic shift from the patriarchal mode to a mono-nuclear mode in the 70's in this specific area, due to a higher resilience of the latter thanks to a broader diversification and a better adequacy between wealth and family demograph

Social Enterprise in Europe: At the Crossroads of Market, Public Policies and Third Sector

Peer reviewe

Spatial fields’ dispersion as a farmer strategy to reduce agro-climatic risk at the household level in pearl millet-based systems in the Sahel: A modeling perspective

The rainfall pattern in the Sahel is very erratic with a high spatial variability. We tested the often reported hypothesis that the dispersion of farmers’ fields around the village territory helps mitigate agro-climatic risk by increasing yield stability from year to year. We also wished to evaluate whether this strategy had an effect on the yield disparity among households in a village. Based on a network of approximately 60 rain gauges spread over 500 km2 in the Fakara region (Southwest Niger), daily rainfall was interpolated at 300 m × 300 m resolution over a 12-year period. This data was used to compute, by means of the APSIM crop simulation model, millet biomass and grain yields at the pixel scale. Simulated yields were combined with the land tenure map of the Banizoumbou village in a GIS to assess millet yield at field and household level. Agro-climatic risk analysis was performed using linear regression between a spatial dispersion index of household fields and the inter-annual (instability) and inter-household (disparity) millet yield variability of 107 households in the village territory. We find that the spatial variability of annual rainfall induces an even higher spatial variability of millet production at pixel, field and household levels. The dispersion of farm fields reduces moderately but significantly the disparity of millet yield between households each year and increases the inter-annual yield stability of a given household. The less the household fields are scattered, the more the presence of a fertility gradient around the village enhances the inter-annual stability but also the disparity between households. Our results provide evidence that field dispersion is an effective strategy to mitigate agro-climatic risk, as claimed by farmers in the Sahelian Niger. Although the results should be confirmed by further research on longer term rainfall spatial data, it is clearly advisable that any land reforms in the area take into account the benefits of field dispersion to mitigate climatic risk

Scenario trees and policy selection for multistage stochastic programming using machine learning

We propose a hybrid algorithmic strategy for complex stochastic optimization problems, which combines the use of scenario trees from multistage stochastic programming with machine learning techniques for learning a policy in the form of a statistical model, in the context of constrained vector-valued decisions. Such a policy allows one to run out-of-sample simulations over a large number of independent scenarios, and obtain a signal on the quality of the approximation scheme used to solve the multistage stochastic program. We propose to apply this fast simulation technique to choose the best tree from a set of scenario trees. A solution scheme is introduced, where several scenario trees with random branching structure are solved in parallel, and where the tree from which the best policy for the true problem could be learned is ultimately retained. Numerical tests show that excellent trade-offs can be achieved between run times and solution quality

Why Social Enterprises Are Asking to Be Multi-stakeholder and Deliberative: An Explanation around the Costs of Exclusion.

The study of multi-stakeholdership (and multi-stakeholder social enterprises in particular) is only at the start. Entrepreneurial choices which have emerged spontaneously, as well as the first legal frameworks approved in this direction, lack an adequate theoretical support. The debate itself is underdeveloped, as the existing understanding of organisations and their aims resist an inclusive, public interest view of enterprise. Our contribution aims at enriching the thin theoretical reflections on multi-stakeholdership, in a context where they are already established, i.e. that of social and personal services. The aim is to provide an economic justification on why the governance structure and decision-making praxis of the firm needs to account for multiple stakeholders. In particular with our analysis we want: a) to consider production and the role of firms in the context of the “public interest” which may or may not coincide with the non-profit objective; b) to ground the explanation of firm governance and processes upon the nature of production and the interconnections between demand and supply side; c) to explain that the costs associated with multi-stakeholder governance and deliberation in decision-making can increase internal efficiency and be “productive” since they lower internal costs and utilise resources that otherwise would go astray. The key insight of this work is that, differently from major interpretations, property costs should be compared with a more comprehensive range of costs, such as the social costs that emerge when the supply of social and personal services is insufficient or when the identification of aims and means is not shared amongst stakeholders. Our model highlights that when social costs derived from exclusion are high, even an enterprise with costly decisional processes, such as the multistakeholder, can be the most efficient solution amongst other possible alternatives