Fixed effects for event types capture the variation in event rate across
different event types (e.g., see Butts, 2008). The specification of FEtype
results in the creation of C-1 statistics, were C is the number of different
event types in the riskset. Let one of the event types, e.g. c = 1,
represent the reference category. Than, for every event type
c = 2, ..., C, a statistic is created that at timepoint t for
dyad (i,j,c) is equal to 1 if c is equal to the respective
event type and equal to 0 otherwise (i.e., dummy variables are created).
Note that specifying fixed effects for event types is only available when
event types are modeled in the dependent variable.