The theory of games against nature relies on complete preferences among all conceivable acts (case 1). Aumann and Drèze (Am Econ J Microecon 1(1):116,(2009) consider situations where preferences are defined only for a given set of acts (case 2).We extend these results to situations where (i)...

This paper is a follow-up to the recommendations made by Jacques Drèze, Edmond Malinvaud and colleagues in 1993 (Drèze, Malinvaud et al., 1994). The key arguments that are of interest for discussion here are paraphrased below: 'For almost 20 years now, West European unemployment has been a...