Richard A. Young, Uncertainty and the Environment. Northhampton, MA, USA: Edward Elgar, 2001, 249 pp.
Uncertainty and the Environment is the result of an interesting doctoral thesis on how George Shackle's ideas of uncertainty might be applied to complex environmental systems. Young makes an important contribution to the field of environmental decision making by exploring how Shackle's work might improve the procedural rationality decisions.
Not surprisingly, the book is structured much like you would expect a well-written dissertation. It begins with an overview of the interdisciplinary literature surrounding uncertainty in ecological and economic systems of interest to economists, geographers, decision theorists, and environmental management researchers. Young describes how Shackie's theory is of use in ecological decisions and provides some background to the case study used in the research. The logical progression of the book was welcome although Young's writing style created the occasional awkward passage. By and large, however, the book was a pleasure to read.
Young argues early in the book for delineation between "hard" and "soft" uncertainty, as in more and less uncertainty respectively. Hard uncertainty reflects the difficulty of predicting outcomes arid probability in highly complex ecological and economic systems. Soft uncertainty, on the other hand, captures more conventional notions of risk, where outcomes and probabilities are both reasonably known. Young then makes the case that hard uncertainty characterizes many environmental decisions, largely because ecosystems under stress have the potential for surprise flips in their function and structure. Coral reefs that become overcome with algae are one example of this type of flip: they shift unpredictably in response to smoothly changing external conditions.
The thrust of Shackle's model, as modified by Young, is this: (1) uncertainty is better measured by "degree of surprise" rather than probability; and (2) decision makers weigh potential outcomes and their degree of surprise according to an "ascendancy function" which measures the "power of this pair [i.e., the outcome and surprise] to arrest the attention of the individual." (p. 90) Degree of surprise differs from probability in that adding up the amount that someone is surprised for all imaginable outcomes does not have to equal one, allowing us to be highly surprised by many different outcomes. However, the sum of the probability of all imaginable outcomes must be one.
Shackle's ideas are not as widely accepted as those from the expected utility school of decision making. Shackle thought of decisions not as repeated events, but rather unique choices that differ over time. …