Inspired by the wide adoption of rigorous randomized controlled trials (RCTs) in medical research, economists and other social scientists have increasingly used RCTs in their research. As researchers pick up projects amenable to the RCT methodology, they likely leave out important questions to which RCTs cannot be directly applied. As a result, RCTs have been criticized for the proclivity of addressing trivial questions. As a matter of fact, in medical research RCTs are an integral part of adaptive sequential experiment designa few steps must be taken to screen out drugs that have toxins and strong side effects before running any RCTs on humans. In this paper, we argue that economists can learn a great deal from the design principles implemented in medical research. We develop a theoretical model to show the logic of adaptive sequential experiment design in the presence of uncertainty over negative effects and discuss how to choose samples in a population to minimize the experiment cost. We also point out the applications of our proposed framework in the economic domain, such as economic reforms and new product design.
This study has been conducted in order to generate evidence of the visibility of exit from farm input subsidies in an African context. The study simulates the impact of alternative exit strategies from Malawis farm input subsidy program on maize markets. The simulation is conducted using a multiequation partial equilibrium model of the national maize market, which is sequentially linked via a price-linkage equation to local rural maize markets. The model accounts for market imperfections prevailing in the country that arise from government price interventions. Findings show that some alternative exit strategies have negative and sustained impacts on maize yields, production, and acreage allocated to maize over the simulation period. Market prices rise steadily as a result of the implementation of different exit strategies. Despite higher maize prices, domestic maize consumption remains fairly stable, with a slow but increasing trend over the simulation period. Results further suggest that exit strategies that are coupled with improvements in agricultural extension services have the potential to offset the negative impacts of the removal or scaling down of agricultural input subsidies. The study findings demonstrate the difficulty of feasibly removing farm input subsidies. Study recommendations are therefore relevant for policymakers and development partners debating removal or implementation of farm input subsidies.
Indias National Rural Employment Guarantee Scheme (NREGS) is one of the largest public works programs globally. Understanding the impacts of NREGS and the pathway through which its impacts are realized thus has important policy implications. We use a three-round 4,000-household panel from Andhra Pradesh together with administrative data to explore short- and medium-term poverty and welfare effects of NREGS. Triple difference estimates suggest that participants significantly increase consumption (protein and energy intake) in the short run and accumulate more nonfinancial assets in the medium term. Direct benefits exceed program-related transfers and are most pronounced for scheduled castes and tribes and households supplying casual labor. Asset creation via program-induced land improvements is consistent with a medium-term increase in assets by nonparticipants and increases in wage income in excess of program cost.
Many development programs that aim to alleviate poverty and improve investments in human capital consider womens empowerment a key pathway by which to achieve impact and often target women as their main beneficiaries. Despite this, womens empowerment dimensions are often not rigorously measured and are at times merely assumed. This paper starts by reflecting on the concept and measurement of womens empowerment and then reviews some of the structural interventions that aim to influence underlying gender norms in society and eradicate gender discrimination. It then proceeds to review the evidence of the impact of three types of interventionscash transfer programs, agricultural interventions, and microfinance programson womens empowerment, nutrition, or both. Qualitative evidence on conditional cash transfer (CCT) programs generally points to positive impacts on womens empowerment, although quantitative research findings are more heterogenous. CCT programs produce mixed results on long-term nutritional status, and very limited evidence exists of their impacts on micronutrient status. The little evidence available on unconditional cash transters (UCT) indicates mixed impacts on womens empowerment and positive impacts on nutrition; however, recent reviews comparing CCT and UCT programs have found little difference in terms of their effects on stunting and they have found that conditionality is less important than other factors, such as access to healthcare and child age and sex. Evidence of cash transfer program impacts depending on the gender of the transfer recipient or on the conditionality is also mixed, although CCTs with non-health conditionalities seem to have negative impacts on nutritional status. The impacts of programs based on the gender of the transfer recipient show mixed results, but almost no experimental evidence exists of testing gender-differentiated impacts of a single program. Agricultural interventionsspecifically home gardening and dairy projectsshow mixed impacts on womens empowerment measures such as time, workload, and control over income; but they demonstrate very little impact on nutrition. Implementation modalities are shown to determine differential impacts in terms of empowerment and nutrition outcomes. With regard to the impact of microfinance on womens empowerment, evidence is also mixed, although more recent reviews do not find any impact on womens empowerment. The impact of microfinance on nutritional status is mixed, with no evidence of impact on micronutrient status. Across all three types of programs (cash transfer programs, agricultural interventions, and microfinance programs), very little evidence exists on pathways of impact, and evidence is often biased toward a particular region. The paper ends with a discussion of the findings and remaining evidence gaps and an outline of recommendations for research.
Markov decision processes have become the de facto standard in modeling and solving sequential decision making problems under uncertainty. This book studies lifting Markov decision processes, reinforcement learning and dynamic programming to the first-order (or, relational) setting.
This Oxford Handbook provides a critical assessment of the history, patterns, and strategies of economic transformation. It deals with major themes including policy issues, illuminating country experiences, and important debates on the respective roles of the market and the state.
Agricultural extension is critical for agricultural growth and food security, but making the extension system effective, demand driven, and responsive to the needs of a diverse set of producers remains a challenge. As part of the institutional reforms in the Democratic Republic of Congo (DRC), the extension system is being reviewed to identify strategies and practical actions to transform the system to better respond to the knowledge needs in a rapidly changing agriculture and food sector. This paper provides an in-depth review of the agricultural extension system of DRC including an analysis of its policies and legal framework, organization, and management; links to critical institutions; and capacity and incentive of different actors in the system. This review involved document analyses, interviews with key informants, and surveys of 107 extension organizations and 162 extension agents in 156 randomly selected villages in western DRC. This review suggests serious funding constraints, human resource management problems, no linkage and coordination within the extension system and with research and education systems, and a majority of underserved communities and farmers. This review also highlights a good opportunity given the huge human resources (more than 11,000 agents) deployed into the sectors and territories as part of the Ministrys agricultural inspection system. However, their mandate is not clear and they currently focus on data collection (census) and checking what farmers do and limited in extension and advisory work. This review highlights the urgent need for human resource or civil service reform; public-sector commitment and funding; infrastructure rebuilding and skills upgrading in extension, education and training, and research organizations; and a unified policy or strategy with clear vision, mandate, targets, and performance-based incentive system.
The past decade has seen several African countries increasing their agricultural growth, a trend largely underpinned by increases in land area cultivated instead of productivity increases. Meanwhile, scholars debate whether Africa should pursue a strategy of large-scale or smallholder farms, paying little attention to a special group of smallholder farmers who have transitioned to become medium- and large-scale farmers. This study, therefore, begins to analyze this group of farmers, using qualitative data from in-depth interviews and focus group discussions in Ghana. We analyze their characteristics, ingredients of farm-size expansion, and commercialization. Numerous insights are gained and hypotheses formulated for future research. One important insight is that with the right attitude, exposure, and discipline, it is possible for smallholder farmers to increase their farm size and commercialize regardless of initial farm enterprise choice. However, to transition, initial farm size and farming system appear critical, with farmers in areas of low population density and flat topography more likely to acquire larger farming land. The transition, however, occurs gradually over 20 to 30 years, with mean annual land acquisition rates ranging from 0.3 to 24.3 acres per year. In the transition process, large- and medium-scale farmers are found to increase their use of modern farm inputs (such as fertilizer and high-yielding seed varieties) and agricultural technologies (such as tractors and processing machinery) and appear more productive than smallholder farmers. Additional quantitative analyses using representative survey data are, however, needed to substantiate the observed qualitative patterns and to further understand the trajectories of farm size expansion and the implications for agricultural productivity and commercialization.
Demand heterogeneity often makes it profitable for firms to price and promote goods and services differently in different market segments. When private consumption brings public benefits, this same heterogeneity can be used to target public subsidies. We explore the design of publicprivate targeting and segmentation strategies in the case of a resource-conserving agricultural technology in India. To understand farmers heterogeneous demand for laser land leveling (LLL), we conducted an experimental auction for LLL services with an integrated randomized controlled trial to estimate the private benefits of the technology. We use graphical and econometric approaches to characterize farmer demand for LLL. We then add detailed cost data from LLL providers to simulate and evaluate several potential targeted delivery strategies based on measures of (1) the cost-effectiveness of expanding LLL dissemination, (2) water savings, and (3) market surplus in a welfare framework. These simulations demonstrate inherent tradeoffs between increasing the amount of land that is leveled and expanding the number of farmers who adopt the technology, and between adoption and water savings. While segmenting and targeting are popular elements of many publicprivate partnerships to develop and disseminate agricultural technologies, formulating and implementing effective delivery strategies requires a rich understanding of costs, benefits, and demand. Our experimental approach generates such an understanding and may be relevant in other contexts.
