Roman Frigg: Making confident decisions with model ensembles

Colloquium lecture by Roman Frigg (Centre for Philosophy of Natural and Social Science, LSE), organized by the Department of Theoretical Philosophy

Increasingly, many policy decisions take input from collections of scientific models. Such decisions face significant and often poorly understood uncertainty. We present a recently developed theory of decision-making under severe uncertainty—called the “confidence approach”—and rework it so that it is able to tackle decision-making with multiple models. We discuss the conditions under which particular sets are available to decision-makers. We illustrate the approach with a case study: an insurance pricing decision using hurricane models. The confidence approach has important consequences for this case, and offers a powerful framework for a wide class of problems. We end with a consideration of different methods for nested set construction, appropriate to different collections of models.