New Move Operators Clause Samples

New Move Operators. The two new move operators are FlipSchedule and ExtendAwayTrip. FlipSchedule is a drastic move operator that aims to radically change the candidate solution. This diversifying operator facilitates moving away from a local optimum in order to find a global optimum. ExtendAwayTrip slightly changes the GroupingAwayUsingByes operator by always adapting the schedule of the team that has to travel the most. This is implemented to increase the equitability of the schedules of all teams. The objective function of a schedule C(S) is mainly determined by the sequence of games all teams play. Inverting a complete schedule has no impact on the value of the objective function. However, inverting only part of the schedule potentially improves the objective function, since changes occur at the ‘edges’ of the inverted region. The move operator FlipSchedule is both applicable for TTP and RTTP instances. It can be seen as a series of SwapRoundsRTTP operators and as an adaptation of the ShiftMove operator created by ▇▇▇▇ et al. (2007). The method starts by randomly selecting 2 rounds, ra and rb (ra < rb). Hereafter, the positions of ra and rb and all intermediate rounds are inverted. This means that ra will become rb, ra + 1 rb 1, ra + 2 rb 2, etc. and finally rb will become ra. The pseudo code for this move operator is given in Algorithm 2. Table 26 provides an example of this move operator. The resulting schedule is not feasible since the no-repeat constraint is violated 4 times, in r3 for t1 and t3, as well as in r7 for t1 and t4. 1: procedure Flip Schedule(S) 2: ra < rb|r ∈ R 3: for m = 0, . . . , | rb−ra ∫ do 4: S∗ ← SwapRounds(ra + m, rb − m) 5: end for 6: return S∗ 1 2 3 4 5 6 7 8 9 2 3 -4 0 0 0 -3 4 -2 -1 4 -3 -4 3 0 0 0 1 4 -1 2 0 -2 -4 1 0 0 -3 -2 1 2 0 3 0 -1 0 1 2 3 4 5 6 7 8 9 -3 0 0 0 -4 0 0 3 -4 -3 0 3 0 2 1 Table 26: Example FlipSchedule(S, r3, r7) The move operator ExtendAwayTrip combines an away trip of length 1 with one of length 2. First, the operator orders the teams in increasing order of the distance travelled. Second, it selects the first team having away trip of length 1, followed, after one or more home games (and possibly byes), by an away trip of length 2 (or vice versa). If such a team is found, 4 new schedules will be generated. If this team has multiple away trips of length 1 or 2, the rounds are selected randomly. The first schedule is generated by applying the move operator PartialSwapRoundsRTTP . The single away match will be swapped with th...