"The more any quantitative social indicator is used for social decision-making, the more subject it will be to corruption pressures and the more apt it will be to distort and corrupt the social processes it is intended to monitor." (p. 85)
Campbell's law was published in 1976 by Donald T. Campbell, a social psychologist, an experimental social science researcher and the author of many works on research methodology. A popular formulation is: "When a measure becomes a target, it ceases to be a good measure." - this is also called Goodhart's law.
The social science principle of Campbell's law is sometimes used to point out the negative consequences of high-stakes testing in U.S. classrooms. This may take the form of teaching to the test or outright cheating. An example is The High-Stakes Education Rule as described in the Learning-Disadvantage Gap.
What Campbell also states in this principle is that "achievement tests may well be valuable indicators of general school achievement under conditions of normal teaching aimed at general competence. But when test scores become the goal of the teaching process, they both lose their value as indicators of educational status and distort the educational process in undesirable ways. (Similar biases of course surround the use of objective tests in courses or as entrance examinations.)"
Closely related ideas are known under different names, e.g. Goodhart's law, and the Lucas critique. Another concept related to Campbell's law emerged in 2006 when UK researchers Rebecca Boden and Debbie Epstein published an analysis of evidence-based policy, a practice espoused by Prime Minister Tony Blair. In the paper, Boden and Epstein described how a government that tries to base its policy on evidence can actually end up producing corrupted data because it, "seeks to capture and control the knowledge producing processes to the point where this type of ‘research’ might best be described as ‘policy-based evidence’." (Boden and Epstein 2006: 226)
- Perverse incentive
- Policy-based evidence making
- Reflexivity (social theory)
- Goodhart's law
- Proxy (statistics)
- Campbell, Donald T. "Assessing the impact of planned social change". Evaluation and Program Planning. 2 (1): 67–90. doi:10.1016/0149-7189(79)90048-X.
- What is Campbell's Law Diane Ravich's Blog 25 May, 2012
- Aviv, Rachel (21 July 2014). "Wrong Answer". The New Yorker.
- Managing the Research Imagination? Globalisation and Research in Higher Education. Globalisation, Societies and Education
- Rothstein, Jesse (University of California - Berkeley) "Review of Learning About Teaching" National Education Policy Center, 1/13/11. http://nepc.colorado.edu/thinktank/review-learning-about-teaching
- "Learning About Teaching" Bill & Melinda Gates Foundation, 12/10/10. http://www.gatesfoundation.org/college-ready-education/Documents/preliminary-findings-research-paper.pdf
- Berliner, David C. & Nichols, Sharon L. "High-Stakes Testing Is Putting the Nation At Risk" Education Week, 3/12/07. http://www.edweek.org/ew/articles/2007/03/12/27berliner.h26.html
- Nichols, Sharon L. & Berliner, David C. "The Inevitable Corruption of Indicators and Educators Through High-Stakes Testing" The Great Lakes Center for Education Research & Practice, East Lansing, MI, March 2005. http://epsl.asu.edu/epru/documents/EPSL-0503-101-EPRU.pdf
- Nichols, S. L., & Berlner, D. C. (2007). Collateral Damage: How high-stakes testing corrupts America's schools Cambridge, MA: Harvard Education Press
- Phelps, R. P. (2013, April 15). "Campbell's Law is Like Campbell's Soup: Ubiquitous and Innocuous" Education News. http://www.educationnews.org/education-policy-and-politics/phelps-campbells-law-is-like-the-soup-ubiquitous-innocuous/
- Tony Waters, "Campbell's law, planned social change, Vietnam war deaths, and condom distributions in refuge camps" at Ethnography.com