# Incorporating User Preferences in Many-Objective Optimization using Relation Epsilon-Preferred

### Nicole Drechsler, Andre Sülflow, Rolf Drechsler

#### Abstract

During the last 10 years, many-objective optimization problems, i.e. optimization problems with more than three objectives, are getting more and more important in the area of multi-objective optimization. Many real- world optimization problems consist of more than three mutually dependent subproblems, that have to be considered in parallel. Furthermore, the objectives have different levels of importance. For this, priorities have to be assigned to the objectives. In this paper we present a new model for many-objective optimization called Prio-ε-Preferred, where the objectives can have different levels of priorities or user preferences. This relation is used for ranking a set of solutions such that an ordering of the solutions is determined. Prio-ε- Preferred is controlled by a parameter ε, that is problem specific and has to be adjusted experimentally by the designer. Therefore, we also present an extension called Adapted-ε-Preferred (AEP), that determines the ε values automatically without any user interaction. To demonstrate the efficiency of our approach, experiments are performed.

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#### Paper Citation

#### in Harvard Style

Drechsler N., Sülflow A. and Drechsler R. (2013). **Incorporating User Preferences in Many-Objective Optimization using Relation Epsilon-Preferred** . In *Proceedings of the 5th International Joint Conference on Computational Intelligence - Volume 1: ECTA, (IJCCI 2013)* ISBN 978-989-8565-77-8, pages 67-74. DOI: 10.5220/0004496000670074

#### in Bibtex Style

@conference{ecta13,

author={Nicole Drechsler and Andre Sülflow and Rolf Drechsler},

title={Incorporating User Preferences in Many-Objective Optimization using Relation Epsilon-Preferred},

booktitle={Proceedings of the 5th International Joint Conference on Computational Intelligence - Volume 1: ECTA, (IJCCI 2013)},

year={2013},

pages={67-74},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0004496000670074},

isbn={978-989-8565-77-8},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the 5th International Joint Conference on Computational Intelligence - Volume 1: ECTA, (IJCCI 2013)

TI - Incorporating User Preferences in Many-Objective Optimization using Relation Epsilon-Preferred

SN - 978-989-8565-77-8

AU - Drechsler N.

AU - Sülflow A.

AU - Drechsler R.

PY - 2013

SP - 67

EP - 74

DO - 10.5220/0004496000670074