This paper compares retrospective and prospective analyses of the effect of flip charts on test scores in rural Kenyan schools. Retrospective estimates suggest that flip charts raise test scores by up to 20% of a standard deviation. Yet prospective estimators based on a randomized trial provide no evidence that flip charts increase test scores. One interpretation is that the retrospective results suffered from omitted variable bias. If the direction of this bias were similar in other retrospective analyses of educational inputs in developing countries, the effects of inputs may be more modest than retrospective studies suggest. A difference-in-differences retrospective estimator seems to reduce bias, but it requires additional assumptions and is feasible for only some educational inputs.
Bibliographical noteFunding Information:
This paper is the outcome of a project that is a joint undertaking of many people. Assistance in data collection and analysis was provided by Chris Asoka, Irene Majale, Robert Namunyu, Caroline Nekesa, Stacy Nemeroff, Michael Wambetsa, Polycarp Waswa, and Maureen Wechuli. Invaluable assistance was provided by the staff of International Christelijk Steunfonds: Damary Alembi, Chip Bury, Jos Huizinga, Japheth Mahagwa, Pamela Oranja, and Susan Walji. We thank our discussant at Stanford, Ed Vytlacil, and two anonymous referees. Finally, we are grateful to Mr. Munala, the District Education Officer of Busia, to Mr. Buluma, the inspector of primary schools in Busia, and to the headmasters, teachers, and students of the participating schools. Financial support was provided by the National Science Foundation and the World Bank research committee. The findings, interpretations, and conclusions expressed in this paper are entirely those of the authors. They do not necessarily represent the views of the National Science Foundation, the World Bank, its Executive Directors, or the countries they represent.
Copyright 2004 Elsevier B.V., All rights reserved.
- Developing countries
- Flip charts
- Program evaluation
- Randomized trial