Warren Walker ’63 PhD ’68 approaches planning when the future is deeply uncertain

As Yogi Berra famously observed, “Predictions are very difficult, especially about the future.”   At an Ezra’s Round Table seminar, Warren Walker ’63 PhD ’68 described an alternative to the traditional “Predict and Act” approach to public policymaking. 

Walker, who is Emeritus Professor of Policy Analysis at Delft University of Technology, has spent his career working on real-world public policy applications of operations research.    His approach to what he calls ‘deep uncertainty’ draws upon 40 years of experience at the RAND Corporation in New York City, Santa Monica, and the Netherlands. 

In his talk, he characterized the traditional approach to policy analysis – making assumptions, predicting outcomes, and then choosing a policy – as fraught with the consequences of uncertainty (Donald Rumsfeld’s things “we don’t know we don’t know ”) and liable to lead to costly outcomes.  As examples of the unreliability of predictions, he contrasted predicted Eurostar ridership with the actual number of passengers ten years later, and actual US energy use versus gross national product in 2000 as much lower than predicted in 1975.  

Rather than simply ignoring uncertainty, assuming the future is knowable, using probability distributions to project a trend, or basing a policy on a few scenarios, Walker recommends “Dynamic Adaptive Policies,” i.e., policies that can be adapted as conditions change over time.  Formulating such policies entails using a massive quantity of computer simulations to explore and identify circumstances under which a policy might succeed or fail, developing a ‘policy protection plan’ for a promising policy, and setting up a monitoring system with triggers that set off defensive and corrective actions if needed.

Walker’s approach is being used on several projects in Europe and Asia, including the design of a “Flexible Port” for the Port of Rotterdam, capacity management at Schiphol Airport, water management in the Netherlands in the face of climate change, and water management in several other areas of the world that are vulnerable to climate change.