This post is a classic paper by Peter Rossi from 1987 (Research in Social Problems and Public Policy, Volume 4, pages 3-20), which addresses a chronic problem in all policy efforts to change complex social systems. The social organizations of modern life are so large, so complex, so dependent on the cooperation of so many actors and agencies that making measurable changes in these organizations of the kind intended by the policymakers is fiendishly difficult. These problems become particularly visible through the process of program evaluation. As a result, Rossi comes up with a set of “laws” that govern the evaluation process.
The Iron Law of Evaluation: The expected value of any net impact
assessment of any large scale social program is zero.
The Stainless Steel Law of Evaluation: The better designed the
impact assessment of social program. the more likely is the resulting estimate of net impact to be zero.
The Brass Law of Evaluation: The more social programs are designed to change individuals, the more likely the net impact of the program will be zero.
The Zinc Law of Evaluation: Only those programs that are likely to
fail are evaluated.
Read this lovely piece and you will get a rich sense of how hard it is to design policies that will effect the kind of change that the policies aims to accomplish. Social organizations have a life of their own whose momentum is difficult to deflect.
Here’s a link to the original paper.
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