The purpose of this paper is two-fold. First, in the context of a spatial model we generalize two indices. One is a dynamic generalization of the emanating effect that was introduced by Kelejian and colleagues. This index describes how events in one unit spill over time to other units due to spatial interactions. As an analogy, it corresponds to the effect that the smoking habits of a given teenager might have on the smoking habits of each of his/her friends.