Step out - Step in Sequencing Games

In this paper a new class of relaxed sequencing games is introduced: the class<br/>of Step out - Step in sequencing games. In this relaxation any player within a coalition is allowed to step out from his position in the processing order and to<br/>step in at any position later in the processing order. Providing an upper bound on<br/>the values of the coalitions we show that every Step out - Step in sequencing game<br/>has a non-empty core. This upper bound is a sufficient condition for a sequencing<br/>game to have a non-empty core. Moreover, this paper provides a polynomial time<br/>algorithm to determine the coalitional values of Step out - Step in sequencing games.