We study a class of two-player continuous time stochastic games in which agents can make (costly) discrete or discontinuous changes in the variables that affect their payoffs. It is shown that in these games there are Markov perfect equilibria of the two-sided (s,S) rule type. In such equilibria...

After the initial breakthrough in the research phase of R&D a new product undergoes a process of change, improvement and adaptation to market conditions. We model the strategic behavior of firms in this development phase of R&D. We emphasize that a key dimension to this competition is the...