My research lies at the intersection of Agricultural Economics,  International Development, and Trade.  In my ongoing dissertation, I assess the determinants and impacts of sustainable input intensification in African agriculture. I'm an applied economist using micro-econometrics, time series, and computable general equilibrium models to analyze issues related to production, transformation, and commercialization of agricultural products. Below are my completed and ongoing research papers.

Dissertation Research (ongoing) : Essays in Sustainable Input Intensification in African Agriculture
  1. “Spillover effects of fertilizer subsidies on the adoption of modern inputs: panel data evidence from Burkina Faso” (Job Market Paper)

    To address the dual problem of limited physical and economic access to modern agricultural inputs, the Government of Burkina Faso initiated a program in 2008 to provide mineral fertilizer to farmers at a 15%-30% discount. The program focuses singularly on mineral fertilizer, targets strategic food crops - maize and rice-, and is universal. Exploiting these unique features, I assess the spillover effects of subsidizing only one agricultural input on the use of other modern inputs in African agriculture. The empirical analysis uses panel data to test the hypothesis that farmers may be using fertilizer as a substitute for—rather than a complement to—other  technologies. It addresses the issues of simultaneity in input use decisions, unobserved heterogeneity, and endogeneity by using multivariate probit, combined with the control function/instrumental variable approach and correlated random effects. The results confirm the endogeneity of access to subsidies and the simultaneity of input use decisions. We find that fertilizer subsidies increase mineral fertilizer use, crowd in the use of hybrid seeds and crop protection chemicals, but crowd out the use of manure. Given the beneficial effects of manure on soil structure and fertility, the results suggest that—for sustainable input intensification—mineral fertilizer subsidies need to be implemented in conjunction with measures to promote or maintain manure use.

  2. “Land rental, farm investment, productivity, and efficiency in Burkina Faso” (Dissertation Essay) with Yoko Kusunose and Veronique Theriault

    Rural land rental markets continue to develop progressively in Sub-Saharan African and represent an increasingly important medium for land transfer among households. We use a nationally-representative household panel from Burkina Faso to identify the determinants of farmers’ participation in these markets and assess the impacts on farm investment and production efficiency. Using a double hurdle model, we find that a household’s farming ability and commitment to agriculture is positively correlated with the likelihood to rent in land and the amount of land rented in. This result corroborates previous findings in both Africa and elsewhere that land rental markets transfer land resource from less talented (or committed) farmers to the more able ones. We look beyond simple correlations by using a multivariable probit regression and the correlated random effects approach to account for unobserved household heterogeneity and potential endogeneity. We find that input use decisions are made jointly, and farmer’s participation in land rental markets has a positive effect on the likelihood to use crop protection chemicals. The effects on mineral fertilizer and organic manure are positive but weak, and there is no significant effect on the use hybrid seeds or hired labor. However, using stochastic production frontier analysis, we find that land renters are better farm managers and experience fewer inefficiencies in their production processes. Taken together, our findings highlight the mixed effects on input intensification of policies that foster the development of land rental markets in Burkina Faso. Much of the gains from these policies might be essentially in terms of increased efficiency of inputs and not necessarily the use of more inputs.                                                                                                                                                                  n
  3. The productivity and welfare effects of the increased prevalence of crop protection chemicals in African agriculture (In progress)

    For decades, much of the focus in agricultural policies has been on increasing crop productivity through the adoption of modern varieties and the use of mineral fertilizer. However, crop production in an African environment is vulnerable to various biotic stressors such as weeds and pests. Weed competition, in particular, is an important constraint that widens the gap between observed crop yields and potential yields. During the past decade, there has been increased use of crop protectants such as herbicides and pesticides in food-crop production. This increase was triggered by the drastic decline in the price of glyphosate as Monsanto’s patent for Roundup expired in 2000. The objective of this study is to assess the impact of the recent increase in herbicide use on a broad range of outcomes, with a special focus on both cash constraints and time constraints. Herbicides may have an outsize effect in relaxing the time constraints for household members, particularly women, on whom the burden of weeding traditionally falls. However, herbicide application also entails the non-trivial fixed cost of a backpack sprayer. We use household panel data from the World Bank Living Standards Measurement - Integrated Survey of Agriculture for Nigeria, Tanzania, and Ethiopia, which are large agricultural production counties. We address several questions. First, what drives household demand for herbicide use? Next, we analyze the productivity differential among households using herbicide and those who do not, and more generally how crop yields respond to the application of these chemicals. Finally, we assess the effect of adoption of herbicide on total farm size, labor costs, off-farm employment, and household income.
 
Journal Articles
  1. Destination or Distraction? Querying the Linkage between Off-farm Income and Farm Investments in Kenya” with Melinda Smale, Yoko Kusunose, and Mary Mathenge. Journal of African Economies, 2016. 25 (3): 388-41
  2. On poverty and persistence of poverty in Benin” with Katia Jossa-Jouable and Rose Fiamohe. Journal of Economic Studies, 2016, 43(4): 661 - 676
  3. “Progress toward the Sustainable Development Goal on poverty: Assessing the effect of income growth on the exit time out of poverty in Benin.” Sustainable Development (forthcoming)
  4. “Altruism or exchange? A quest into the motives of inter-household private transfers in Burkina Faso.” with Nicholas Ponty and Ignace Kamga, International Journal of Socio-Economics (forthcoming)
  5. Geographical orientation of export in the manufacturing sector in sub-Sahara Africa”. Global Economy Journal, 2015, 15 (3) 337–351
  6. Transmission of rice prices from Thailand into West African markets: The case of Benin, Mali, and Senegal” with Rose Fiamohe, Ibrahim Bamba, Aliou Diagne, and Eyram Amovin-Assagba. Journal of African Business, 2015, 16(1-2): 128-143
  7. Price transmission analysis using threshold models: an application to local rice markets in Benin and Mali” with Fiamohe, Ibrahim Bamba, Aliou Diagne. Food security, 2013. 5(3), 427-438

Book Chapters
  1. Farmer Perceptions of the Biophysical Constraints to Rice Production in Sub-Saharan Africa, and Potential Impact of Research”. (with Aliou Diagne, Eyram Amovin-Assagba, Marco C.S. Wopereis and Kazuki Saito), chapter in Realizing Africa’s Rice Promise. Wopereis, M.C.S., Johnson, D.E., Ahmadi N., Tollens, E. and Jalloh, A., CABI Publishing, October 2013
  2. Impact of Rice Research on Income, Poverty and Food Security in Africa: An Ex-ante Analysis”. (with Aliou Diagne, Marco C.S. Wopereis, Kazuki Saito and Papa Abdoulaye Seck) chapter in Realizing Africa’s Rice Promise. Wopereis, M.C.S., Johnson, D.E., Ahmadi N., Tollens, E. and Jalloh, A., CABI Publishing, October 2013

Papers under review

  1. “Cross-markets transmission of price and price volatility in international grain markets” with Michael Reed, Under Review
  2. “Foreign aid effectiveness in African economies: evidence from a threshold panel” with Romuald Anago, Under Review
  3. “Heterogeneous welfare effects of cotton pricing on households in Benin” with Anne Floquet and Epiphane Adjovi, Under Review
  4. “Distributional impact of Nerica adoption on farmer expenditure in Benin: Quantile Treatment Effect Estimation” with Aliou Diagne, Patrice Adegbola, and Florent Kinkingninhoue, Under Review
  5. “Estimating the causal effect of trade liberalization on economic growth using treatment effect framework” with Michael Reed and Sayed Saghaian, Under Review

Papers in progress

  1.  “Spillover effects of fertilizer subsidies on the adoption of modern inputs: panel data evidence from Burkina Faso” (Job market paper)
    “Land rental, farm investment, productivity, and efficiency in Burkina Faso”
    (Dissertation Essay 2)
  2. “The productivity and welfare effects of the increased prevalence of crop protection chemicals in African agriculture” (Dissertation Essay 3)
  3. “Spatial urban development and transformation of African agriculture: A view from space” with Christopher Boone
  4. “Institutional change, industrialization and structural change out of agriculture” with Michael Reed and Yoko Kusunose
  5. “Health shocks and agricultural productivity: Panel data evidence from Tanzania”
  6. “Assessing policy coherence for development: Spillover effects of OECD policies on food security in Tanzania” with Fabien Tondel, Solomon, Baregu, Festo Maro, Abel Songole, and Brecht Lein
  7. “Do bilateral investment treaties promote or restrict large-scale land acquisition in developing countries?”
    “Trade effects of food regulations and standards: Assessing the impact of SPS measures on market structure”
  8.  “Assessing the performance of food co-ops in the US” with Ani Katchova and Timothy A. Woods
    “Are non-food cash crops and food crops substitute or complement? Evidence from sub-national panel in Benin”
  9. “The Dynamic Implication of Agricultural Research and Development Investment for Economic Development” with Michael Reed
  10.  “Rural media, agricultural technology adoption and productivity: evidences from small rice farmers in Burkina Faso” with Nakelse Tebila and Diagne Aliou
  11. “Evaluation of the effects of economic policies on informal sector performance and poverty in Cameroon: a Computable General Equilibrium model analysis” with Willy Ndjana, Erith Nghogue and Robert Ngonthe
  12. “The politics of agricultural policies: cotton pricing in election time in West Africa.”