The HighScope Perry Preschool Project was evaluated in a randomized controlled trial of 123 children (58 were randomly assigned to a treatment group that received the program and a control group of 65 children that did not). Prior to the program, the preschool and control groups were equivalent in measures of intellectual performance and demographic characteristics. After the program the educational and life outcomes for the children receiving the program were much superior to outcomes for the children not receiving the program. Many of the program effects were significant or approaching significance.
RAND Health Insurance Experiment
The RAND Health Insurance Experiment was an experimental study of "health care costs, utilization and outcomes in the United States, which assigned people randomly to different kinds of plans and followed their behavior, from 1974 to 1982. As a result, it provided stronger evidence than studies that examine people afterwards who were not randomly assigned. It concluded that "cost sharing reduced "inappropriate or unnecessary" medical care ("overutilization), but also reduced "appropriate or needed" medical care. It did not have enough statistical power to tell whether people who got less appropriate or needed care were more likely to die as a result.
Oportunidades (now rebranded as "Prospera" ) is a government social assistance ("welfare) program in "Mexico founded in 2002, based on a previous program called Progresa, created in 1997. It is designed to target poverty by providing cash payments to families in exchange for regular school attendance, health clinic visits, and nutrition support. Oportunidades is credited with decreasing poverty and improving health and educational attainment in regions where it has been deployed.
Moving to Opportunity
Moving to Opportunity for Fair Housing was a randomized social experiment sponsored by the United States "Department of Housing and Urban Development in the 1990s among 4600 low-income families with children living in high-poverty "public housing projects.
Stanford prison experiment
The Stanford prison experiment was a study of the "psychological effects of becoming a "prisoner or "prison guard. The experiment was conducted at "Stanford University on August 14–20, 1971, by a team of researchers led by psychology professor "Philip Zimbardo using college students. It was funded by the "U.S. Office of Naval Research and was of interest to both the "U.S. Navy and "Marine Corps as an investigation into the causes of conflict between military guards and prisoners. The experiment is a classic study on the psychology of imprisonment and is a topic covered in most introductory psychology textbooks.
Experiments by Muzafer Sherif
Sherif was a founder of modern social psychology, who developed several unique and powerful techniques for understanding social processes, particularly social norms and social conflict. Sherif's experimental study of autokinetic movement demonstrated how mental evaluation norms were created by human beings. Sherif is equally famous for the "Robbers Cave Experiments. This series of experiments, begun in Connecticut and concluded in Oklahoma, took boys from intact middle-class families, who were carefully screened to be psychologically normal, delivered them to a summer camp setting (with researchers doubling as counsellors) and created social groups that came into conflict with each other.
- Thomas D. Cook and Donald T. campbell (1979): Quasi-experimentation: Design and Analysis Issues for Field Settings. Houghton Mifflin, "ISBN 978-0-39-530790-8
- Robins, Philip K; Spiegelman, Robert G; Weiner, Samuel (1980). A Guaranteed Annual Income: Evidence from a Social Experiment. New York, New York: Academic Press.
- "Campbell, Donald T. (1969). "Reforms as Experiments". "American Psychologist. 24 (4): 409–429. "doi:10.1037/h0027982.
- David Greenberg and Mark Shroder. "The Digest of Social Experiments, Third Edition". Retrieved December 9, 2011.
- Significant Benefits, The High/Scope Perry Preschool Study Through Age 27
- Coalition for Evidence-Based Policy: Social Programs That Work: Perry Preschool Project
- Paying for Better Parenting, New York Times, Accessed 12/07/06
- Mexico's Oportunidades Program Accessed 12/07/06
- Bulletin of the World Health Organization - Reaching Mexico's poorest Accessed 12/07/06
- The Stanford Prison Experiment – A Simulation Study of the Psychology of Imprisonment Conducted at Stanford University
- FAQ on official site
- Intro to psychology textbooks gloss over criticisms of Zimbardo's Stanford Prison Experiment
- Jaan Valsiner. Comparative study of human cultural development. Fundacion Infancia y Aprendizaje.