Aliasing in XCS and the Consecutive State Problem: 2 - solutions
Alwyn M. Barry · 1999
The 'Aliasing Problem' within XCS (Wilson, 1995, 1998), first identified by Lanzi (1997), does not only appear whenever the aliased states occur in separate environmental locations but also when they occur consecutively (Barry, 1999). Lanzi (1997, 1998) introduced a mechanism that could solve the Aliasing Problem through the use of memory mechanisms within XCS (Wilson, 1995; Cliff and Ross, 1994). Whilst this mechanism is a solution to the general problem of aliasing, it is a heavyweight solution. By limiting the scope of a solution to the Consecutive State Problem, which is shown to be a sub-problem of the Aliasing Problem, a simpler solution is proposed, and is shown to adequately address this problem. The application of a potential solution utilising explicit action duration identification is discussed and shown to be inadequate both as a solution to the Consecutive State Problem and for more general use within XCS.