External Evaluator Team

External Evaluator Team

Evaluation Leadership

Tulika Narayan

Research Director

Dr. Narayan is Principal Associates at Abt Associates and an agricultural and development economist. She brings over 15 years of experience conducting economic analysis to support agricultural and low-emissions development as well as evaluation of international development interventions. She provides research leadership to AgResults evaluation, ensuring that all pilots are evaluated using the common theoretical framework and integrating quantitative and qualitative analysis. Dr. Narayan holds a Ph.D. in agricultural and natural resource economics from the University of Maryland, College Park.

Stephen Bell

Quality Assurance Officer

Dr. Bell is a Vice President and Senior Fellow at Abt Associates with 30 years of experience designing and executing large-scale evaluations of social interventions in the U.S. and developing countries. As quality assurance officer for the AgResults evaluation, Dr. Bell advises the technical team at key phases in the evaluations and ensures proper review and quality assurance on all evaluation deliverables. He holds a Ph.D. in economics from the University of Wisconsin-Madison and has published widely on impact evaluation methodology.

 Denise Mainville

Qualitative Analysis Lead

Dr. Mainville, under sub-contract to Abt, is an agricultural economist specialized in agri-food market development. Her 15 years of experience in international agricultural research, development, and outreach have focused on enhancing complementarities between private sector activity and development outcomes, with field activities in Africa, Latin America and the Caribbean, and Asia. She leads the qualitative study design and implementation to assess AgResults’ impact on markets. Dr. Mainville has numerous publications and a Ph.D. in agricultural economics from Michigan State University.

 Judy Geyer

Quantitative Analysis Lead

Dr. Geyer is an economist specializing in applied econometric methods and policy analysis, including the design of randomized control trials, quasi-experimental evaluation, and structural choice modeling. Her background includes several years of experience in analyzing the dynamics of social program participation, and market and behavioral responses to incentive mechanisms. She provides expertise to the AgResults team in evaluation design and the management of quantitative analysis tasks. Dr. Geyer holds a Ph.D. in economics from Carnegie Mellon University.


Abigail Conrad

Dr. Conrad is an applied anthropologist with experience designing and executing qualitative research to study behavior change, farming systems, food and nutrition security, and health seeking behavior. She provides expertise in rigorous qualitative research design, data collection, and analysis to complex, multi-country agriculture sector and health systems evaluations across sub-Saharan Africa. She designs qualitative study protocols and carries out qualitative research for the AgResults evaluation, specifically for the Zambia and brucellosis evaluations. Dr. Conrad holds a Ph.D. in anthropology from American University.

Betsy Ness-Edelstein

Betsy Ness-Edelstein is an evaluation specialist focusing on agriculture, nutrition, and microfinance programs. She has experience designing evaluations, training and supervising data collection teams, performing analysis, and disseminating results to stakeholders. She manages evaluation designs and implementations, focusing on the Kenya and Uganda pilots. Ms. Ness-Edelstein holds an M.A. in development economics and international business from Tufts University’s Fletcher School of Law and Diplomacy.


Abt Associates also draws on its in-house evaluation resources and forums for collaboration, which include the Evaluation and Monitoring Methods Center, the Policy Analysis Methods Center, the Qualitative Methods Center, and the Journal Author Support Group seminars.

The AgResults initiative is a partnership between: