Survival analysis, generally speaking, is the modeling of time-to-event data. Traditionally, survival analysis has been used to study the survival of [Page 1477]biological organisms, including human beings and laboratory animals. In this instance, survival analysis seeks to determine the amount of time until the death of the organism. The death is considered the event, and the time until the event is what is modeled. In such instances, survival analysis can determine the proportion of organisms alive at a certain point in time. Furthermore, factors to increase (or shorten) the life span of the organism can be determined. Survival analysis has been applied to many other fields to model data that are not specifically the “life” and “death” of an organism. For instance, survival analysis has ...