Fast and exact audit scheduling optimization

TL;DR

This paper presents a fast and exact optimization method for scheduling financial auditors using Integer Linear Programming, significantly reducing scheduling time and efficiently handling multiple constraints and frequent data changes.

Contribution

It introduces a multi-commodity network flow formulation that outperforms previous models in speed and scalability for audit scheduling optimization.

Findings

Multi-commodity network flow formulation is 24 times faster.

Schedule generation reduced from 3 man-days to 1 hour.

Schedule update time decreased from 1 day to 4 minutes.

Abstract

This article is concerned with the cost and time effective scheduling of financial auditors with Integer Linear Programming. The schedule optimization takes into account 13 different constraints, staff scarcity, frequent alterations of the input data with the need to minimize the changes in the generated schedule, and scaling issues. We compared two exact formulations of the problem and we found a multi-commodity network flow formulation to be 24 times faster than a three-dimensional formulation. The delivered implementation reduced time to the first schedule from 3 man-days to 1 hour and the schedule update time from 1 man-day to 4 minutes.