The Doctor Rostering Problem - Asser Fahrenholz

Chapter 7. Tests, results and discussion 52
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(a) Test 2: SA, R2, RCL 1%
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Figure 7.6: SA performance: Test 2 and 5
(b) Test 5: SA, R2, RCL 50%
fact that the Z(S) can increase, sometimes ten-fold, as SA makes V(S) decrease towards
0.
Secondly, an use-case evaluation, given the test results in this chapter, brings me to
the conclusion that GRASP with enumeration, RCL 1-5 % and a number of iterations
between 5000 and 10000, would yield the best results of all possible combinations.
Had there been time to do so, it would have been of great importance to test following:
• Solving test-instances with GAMS, yielding proven bounds and comparing the
heuristic solutions to these bounds.
• How the initial temperature and update of the temperature affects the performance
of SA.
• How a skew distribution of weights would have affected the results of both GRASP
and SA.
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