Journal of Combinatorial Optimization

, Volume 19, Issue 3, pp 325–346 | Cite as

Scheduling internal audit activities: a stochastic combinatorial optimization problem

  • Roberto RossiEmail author
  • S. Armagan Tarim
  • Brahim Hnich
  • Steven Prestwich
  • Semra Karacaer
Open Access


The problem of finding the optimal timing of audit activities within an organisation has been addressed by many researchers. We propose a stochastic programming formulation with Mixed Integer Linear Programming (MILP) and Constraint Programming (CP) certainty-equivalent models. In experiments neither approach dominates the other. However, the CP approach is orders of magnitude faster for large audit times, and almost as fast as the MILP approach for small audit times. This work generalises a previous approach by relaxing the assumption of instantaneous audits, and by prohibiting concurrent auditing.


Uncertainty Audit scheduling Combinatorial optimization Mathematical programming Constraint programming 


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Copyright information

© The Author(s) 2009

Authors and Affiliations

  • Roberto Rossi
    • 1
    • 2
    Email author
  • S. Armagan Tarim
    • 3
  • Brahim Hnich
    • 4
  • Steven Prestwich
    • 1
  • Semra Karacaer
    • 3
  1. 1.Cork Constraint Computation CentreUniversity CollegeCorkIreland
  2. 2.Centre for Telecommunication Value-Chain Driven ResearchUniversity CollegeDublinIreland
  3. 3.Department of ManagementHacettepe UniversityAnkaraTurkey
  4. 4.Faculty of Computer ScienceIzmir University of EconomicsIzmirTurkey

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