Stephen Bell

Vice President

Stephen H. Bell, Ph.D., is a senior economist with extensive experience evaluating the effects of social and market interventions on the well-being of disadvantaged Americans and poor people worldwide.

Dr. Bell specializes in econometric impact analysis. He has helped design many large-scale social experiments using random assignment in the United States, the United Kingdom, and Italy. Dr. Bell is also an expert in the use of quasi-experimental estimation techniques when randomization is not possible. His recent work has focused on experimental trials of employment assistance, housing and nutrition interventions, and international agricultural development initiatives.

Dr. Bell has led evaluation studies to support the U.S. Departments of Labor, Health & Human Services, Agriculture, Education, and Housing & Urban Development—as well as the U.S. Agency for International Development and the Social Security Administration. His original methodologies for measuring the impacts of social programs have been published in several peer-reviewed statistics and evaluation journals, a U.S. Department of Labor field guide on evaluation methods, and a book on quasi-experimental impact analysis techniques. Dr. Bell is a recipient of the Raymond Vernon Memorial Award for the best article published in the Journal of Policy Analysis and Management in 2018.

In recognition of his contributions to the field, Dr. Bell has been named a Westat Senior Statistical Fellow and serves on the Statistical Fellows Committee, which provides consultation on important survey statistics issues and addresses recent advances in applied statistics.


Ph.D., Economics, University of Wisconsin–Madison
M.S., Economics, University of Wisconsin–Madison
B.A. (magna cum laude), Economics, Knox College

Areas of Expertise

Selected Publications

Orr L.L., Olsen R.B., Bell S.H., Schmid I., Shivji A., and Stuart E.A. (2019).

Using the results from rigorous multisite evaluations to inform local policy decisions.

Gubits D., Shinn M., Wood M., Brown S.R., Dastrup S.R., and Bell S.H. (2018).

What interventions work best for families who experience homelessness? Impact estimates from the Family Options Study.

Collins A.M., Klerman J.A., Briefel R., Rowe G., Gordon A., Logan C., Wolf A., and Bell S.H. (2018).

A summer nutrition benefit pilot program and low-income children's food security.

Olsen R.B., Bell S.H., and Nichols A. (2018).

Using preferred applicant random assignment (PARA) to reduce randomization bias in randomized trials of discretionary programs.

Klerman J.A., Wolf A., Collins A.M., Bell S.H., and Briefel R. (2017).

The effects the Summer Electronic Benefits Transfer for Children Demonstration has on children’s food security.

Stuart E.A., Bell S.H., Ebnesajjad C., Olsen R.B., and Orr L.L. (2017).

Characteristics of school districts that participate in rigorous national educational evaluations.

Bell S.H. and Peck L.R. (2016).

On the “how” of social experiments: Experimental designs for getting inside the black box.

Bell S.H. and Stuart E.A. (2016).

On the “Where” of social experiments: The nature and extent of the generalizability problem.

Bell S.H. and Peck L.R. (2016).

On the feasibility of extending social experiments to wider applications.

Bell S.H., Olsen R.B., Orr L.L., and Stuart E.A. (2016).

Estimates of external validity bias when impact evaluations select sites nonrandomly.

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