Blameworthiness in Strategic Games

There are multiple notions of coalitional responsibility. The focus of this paper is on the blameworthiness defined through the principle of alternative possibilities: a coalition is blamable for a statement if the statement is true, but the coalition had a strategy to prevent it. The main technical result is a sound and complete bimodal logical system that describes properties of blameworthiness in one-shot games

Reasoning about Choice

We present a logic for reasoning about choice. Choice ctl (c-ctl) extends the well-known branching-time temporal logic ctl with choice modalities, " ◊ " and "□". An example c-ctl formula is ◊ AF happy, asserting that there exists a choice that will lead to happiness. c-ctl is related to both stit logics and temporal cooperation logics such as atl, but has a much simpler and (we argue) more intuitive syntax and semantics. After presenting the logic, we investigate the properties of the language. We characterise the complexity of the c-ctl model checking problem, investigate some validities, and propose multi-agent extensions to the logic