---
_id: '48894'
abstract:
- lang: eng
  text: Recently different evolutionary computation approaches have been developed
    that generate sets of high quality diverse solutions for a given optimisation
    problem. Many studies have considered diversity 1) as a mean to explore niches
    in behavioural space (quality diversity) or 2) to increase the structural differences
    of solutions (evolutionary diversity optimisation). In this study, we introduce
    a co-evolutionary algorithm to simultaneously explore the two spaces for the multi-component
    traveling thief problem. The results show the capability of the co-evolutionary
    algorithm to achieve significantly higher diversity compared to the baseline evolutionary
    diversity algorithms from the literature.
author:
- first_name: Adel
  full_name: Nikfarjam, Adel
  last_name: Nikfarjam
- first_name: Aneta
  full_name: Neumann, Aneta
  last_name: Neumann
- first_name: Jakob
  full_name: Bossek, Jakob
  id: '102979'
  last_name: Bossek
  orcid: 0000-0002-4121-4668
- first_name: Frank
  full_name: Neumann, Frank
  last_name: Neumann
citation:
  ama: 'Nikfarjam A, Neumann A, Bossek J, Neumann F. Co-Evolutionary Diversity Optimisation
    for the Traveling Thief Problem. In: Rudolph G, Kononova AV, Aguirre H, Kerschke
    P, Ochoa G, Tu\v sar T, eds. <i>Parallel Problem Solving from Nature (PPSN XVII)</i>.
    Lecture Notes in Computer Science. Springer International Publishing; 2022:237–249.
    doi:<a href="https://doi.org/10.1007/978-3-031-14714-2_17">10.1007/978-3-031-14714-2_17</a>'
  apa: Nikfarjam, A., Neumann, A., Bossek, J., &#38; Neumann, F. (2022). Co-Evolutionary
    Diversity Optimisation for the Traveling Thief Problem. In G. Rudolph, A. V. Kononova,
    H. Aguirre, P. Kerschke, G. Ochoa, &#38; T. Tu\v sar (Eds.), <i>Parallel Problem
    Solving from Nature (PPSN XVII)</i> (pp. 237–249). Springer International Publishing.
    <a href="https://doi.org/10.1007/978-3-031-14714-2_17">https://doi.org/10.1007/978-3-031-14714-2_17</a>
  bibtex: '@inproceedings{Nikfarjam_Neumann_Bossek_Neumann_2022, place={Cham}, series={Lecture
    Notes in Computer Science}, title={Co-Evolutionary Diversity Optimisation for
    the Traveling Thief Problem}, DOI={<a href="https://doi.org/10.1007/978-3-031-14714-2_17">10.1007/978-3-031-14714-2_17</a>},
    booktitle={Parallel Problem Solving from Nature (PPSN XVII)}, publisher={Springer
    International Publishing}, author={Nikfarjam, Adel and Neumann, Aneta and Bossek,
    Jakob and Neumann, Frank}, editor={Rudolph, Günter and Kononova, Anna V. and Aguirre,
    Hernán and Kerschke, Pascal and Ochoa, Gabriela and Tu\v sar, Tea}, year={2022},
    pages={237–249}, collection={Lecture Notes in Computer Science} }'
  chicago: 'Nikfarjam, Adel, Aneta Neumann, Jakob Bossek, and Frank Neumann. “Co-Evolutionary
    Diversity Optimisation for the Traveling Thief Problem.” In <i>Parallel Problem
    Solving from Nature (PPSN XVII)</i>, edited by Günter Rudolph, Anna V. Kononova,
    Hernán Aguirre, Pascal Kerschke, Gabriela Ochoa, and Tea Tu\v sar, 237–249. Lecture
    Notes in Computer Science. Cham: Springer International Publishing, 2022. <a href="https://doi.org/10.1007/978-3-031-14714-2_17">https://doi.org/10.1007/978-3-031-14714-2_17</a>.'
  ieee: 'A. Nikfarjam, A. Neumann, J. Bossek, and F. Neumann, “Co-Evolutionary Diversity
    Optimisation for the Traveling Thief Problem,” in <i>Parallel Problem Solving
    from Nature (PPSN XVII)</i>, 2022, pp. 237–249, doi: <a href="https://doi.org/10.1007/978-3-031-14714-2_17">10.1007/978-3-031-14714-2_17</a>.'
  mla: Nikfarjam, Adel, et al. “Co-Evolutionary Diversity Optimisation for the Traveling
    Thief Problem.” <i>Parallel Problem Solving from Nature (PPSN XVII)</i>, edited
    by Günter Rudolph et al., Springer International Publishing, 2022, pp. 237–249,
    doi:<a href="https://doi.org/10.1007/978-3-031-14714-2_17">10.1007/978-3-031-14714-2_17</a>.
  short: 'A. Nikfarjam, A. Neumann, J. Bossek, F. Neumann, in: G. Rudolph, A.V. Kononova,
    H. Aguirre, P. Kerschke, G. Ochoa, T. Tu\v sar (Eds.), Parallel Problem Solving
    from Nature (PPSN XVII), Springer International Publishing, Cham, 2022, pp. 237–249.'
date_created: 2023-11-14T15:59:00Z
date_updated: 2023-12-13T10:49:51Z
department:
- _id: '819'
doi: 10.1007/978-3-031-14714-2_17
editor:
- first_name: Günter
  full_name: Rudolph, Günter
  last_name: Rudolph
- first_name: Anna V.
  full_name: Kononova, Anna V.
  last_name: Kononova
- first_name: Hernán
  full_name: Aguirre, Hernán
  last_name: Aguirre
- first_name: Pascal
  full_name: Kerschke, Pascal
  last_name: Kerschke
- first_name: Gabriela
  full_name: Ochoa, Gabriela
  last_name: Ochoa
- first_name: Tea
  full_name: Tu\v sar, Tea
  last_name: Tu\v sar
extern: '1'
keyword:
- Co-evolutionary algorithms
- Evolutionary diversity optimisation
- Quality diversity
- Traveling thief problem
language:
- iso: eng
page: 237–249
place: Cham
publication: Parallel Problem Solving from Nature (PPSN XVII)
publication_identifier:
  isbn:
  - 978-3-031-14714-2
publication_status: published
publisher: Springer International Publishing
series_title: Lecture Notes in Computer Science
status: public
title: Co-Evolutionary Diversity Optimisation for the Traveling Thief Problem
type: conference
user_id: '102979'
year: '2022'
...
---
_id: '48893'
abstract:
- lang: eng
  text: Computing diverse sets of high-quality solutions has gained increasing attention
    among the evolutionary computation community in recent years. It allows practitioners
    to choose from a set of high-quality alternatives. In this paper, we employ a
    population diversity measure, called the high-order entropy measure, in an evolutionary
    algorithm to compute a diverse set of high-quality solutions for the Traveling
    Salesperson Problem. In contrast to previous studies, our approach allows diversifying
    segments of tours containing several edges based on the entropy measure. We examine
    the resulting evolutionary diversity optimisation approach precisely in terms
    of the final set of solutions and theoretical properties. Experimental results
    show significant improvements compared to a recently proposed edge-based diversity
    optimisation approach when working with a large population of solutions or long
    segments.
author:
- first_name: Adel
  full_name: Nikfarjam, Adel
  last_name: Nikfarjam
- first_name: Jakob
  full_name: Bossek, Jakob
  id: '102979'
  last_name: Bossek
  orcid: 0000-0002-4121-4668
- first_name: Aneta
  full_name: Neumann, Aneta
  last_name: Neumann
- first_name: Frank
  full_name: Neumann, Frank
  last_name: Neumann
citation:
  ama: 'Nikfarjam A, Bossek J, Neumann A, Neumann F. Entropy-Based Evolutionary Diversity
    Optimisation for the Traveling Salesperson Problem. In: <i>Proceedings of the
    Genetic and Evolutionary Computation Conference</i>. GECCO’21. Association for
    Computing Machinery; 2021:600–608. doi:<a href="https://doi.org/10.1145/3449639.3459384">10.1145/3449639.3459384</a>'
  apa: Nikfarjam, A., Bossek, J., Neumann, A., &#38; Neumann, F. (2021). Entropy-Based
    Evolutionary Diversity Optimisation for the Traveling Salesperson Problem. <i>Proceedings
    of the Genetic and Evolutionary Computation Conference</i>, 600–608. <a href="https://doi.org/10.1145/3449639.3459384">https://doi.org/10.1145/3449639.3459384</a>
  bibtex: '@inproceedings{Nikfarjam_Bossek_Neumann_Neumann_2021, place={New York,
    NY, USA}, series={GECCO’21}, title={Entropy-Based Evolutionary Diversity Optimisation
    for the Traveling Salesperson Problem}, DOI={<a href="https://doi.org/10.1145/3449639.3459384">10.1145/3449639.3459384</a>},
    booktitle={Proceedings of the Genetic and Evolutionary Computation Conference},
    publisher={Association for Computing Machinery}, author={Nikfarjam, Adel and Bossek,
    Jakob and Neumann, Aneta and Neumann, Frank}, year={2021}, pages={600–608}, collection={GECCO’21}
    }'
  chicago: 'Nikfarjam, Adel, Jakob Bossek, Aneta Neumann, and Frank Neumann. “Entropy-Based
    Evolutionary Diversity Optimisation for the Traveling Salesperson Problem.” In
    <i>Proceedings of the Genetic and Evolutionary Computation Conference</i>, 600–608.
    GECCO’21. New York, NY, USA: Association for Computing Machinery, 2021. <a href="https://doi.org/10.1145/3449639.3459384">https://doi.org/10.1145/3449639.3459384</a>.'
  ieee: 'A. Nikfarjam, J. Bossek, A. Neumann, and F. Neumann, “Entropy-Based Evolutionary
    Diversity Optimisation for the Traveling Salesperson Problem,” in <i>Proceedings
    of the Genetic and Evolutionary Computation Conference</i>, 2021, pp. 600–608,
    doi: <a href="https://doi.org/10.1145/3449639.3459384">10.1145/3449639.3459384</a>.'
  mla: Nikfarjam, Adel, et al. “Entropy-Based Evolutionary Diversity Optimisation
    for the Traveling Salesperson Problem.” <i>Proceedings of the Genetic and Evolutionary
    Computation Conference</i>, Association for Computing Machinery, 2021, pp. 600–608,
    doi:<a href="https://doi.org/10.1145/3449639.3459384">10.1145/3449639.3459384</a>.
  short: 'A. Nikfarjam, J. Bossek, A. Neumann, F. Neumann, in: Proceedings of the
    Genetic and Evolutionary Computation Conference, Association for Computing Machinery,
    New York, NY, USA, 2021, pp. 600–608.'
date_created: 2023-11-14T15:59:00Z
date_updated: 2023-12-13T10:50:06Z
department:
- _id: '819'
doi: 10.1145/3449639.3459384
extern: '1'
keyword:
- evolutionary algorithms
- evolutionary diversity optimisation
- high-order entropy
- traveling salesperson problem
language:
- iso: eng
page: 600–608
place: New York, NY, USA
publication: Proceedings of the Genetic and Evolutionary Computation Conference
publication_identifier:
  isbn:
  - 978-1-4503-8350-9
publisher: Association for Computing Machinery
series_title: GECCO’21
status: public
title: Entropy-Based Evolutionary Diversity Optimisation for the Traveling Salesperson
  Problem
type: conference
user_id: '102979'
year: '2021'
...
---
_id: '48891'
abstract:
- lang: eng
  text: Submodular functions allow to model many real-world optimisation problems.
    This paper introduces approaches for computing diverse sets of high quality solutions
    for submodular optimisation problems with uniform and knapsack constraints. We
    first present diversifying greedy sampling approaches and analyse them with respect
    to the diversity measured by entropy and the approximation quality of the obtained
    solutions. Afterwards, we introduce an evolutionary diversity optimisation (EDO)
    approach to further improve diversity of the set of solutions. We carry out experimental
    investigations on popular submodular benchmark problems and analyse trade-offs
    in terms of solution quality and diversity of the resulting solution sets.
author:
- first_name: Aneta
  full_name: Neumann, Aneta
  last_name: Neumann
- first_name: Jakob
  full_name: Bossek, Jakob
  id: '102979'
  last_name: Bossek
  orcid: 0000-0002-4121-4668
- first_name: Frank
  full_name: Neumann, Frank
  last_name: Neumann
citation:
  ama: 'Neumann A, Bossek J, Neumann F. Diversifying Greedy Sampling and Evolutionary
    Diversity Optimisation for Constrained Monotone Submodular Functions. In: <i>Proceedings
    of the Genetic and Evolutionary Computation Conference</i>. GECCO’21. Association
    for Computing Machinery; 2021:261–269. doi:<a href="https://doi.org/10.1145/3449639.3459385">10.1145/3449639.3459385</a>'
  apa: Neumann, A., Bossek, J., &#38; Neumann, F. (2021). Diversifying Greedy Sampling
    and Evolutionary Diversity Optimisation for Constrained Monotone Submodular Functions.
    <i>Proceedings of the Genetic and Evolutionary Computation Conference</i>, 261–269.
    <a href="https://doi.org/10.1145/3449639.3459385">https://doi.org/10.1145/3449639.3459385</a>
  bibtex: '@inproceedings{Neumann_Bossek_Neumann_2021, place={New York, NY, USA},
    series={GECCO’21}, title={Diversifying Greedy Sampling and Evolutionary Diversity
    Optimisation for Constrained Monotone Submodular Functions}, DOI={<a href="https://doi.org/10.1145/3449639.3459385">10.1145/3449639.3459385</a>},
    booktitle={Proceedings of the Genetic and Evolutionary Computation Conference},
    publisher={Association for Computing Machinery}, author={Neumann, Aneta and Bossek,
    Jakob and Neumann, Frank}, year={2021}, pages={261–269}, collection={GECCO’21}
    }'
  chicago: 'Neumann, Aneta, Jakob Bossek, and Frank Neumann. “Diversifying Greedy
    Sampling and Evolutionary Diversity Optimisation for Constrained Monotone Submodular
    Functions.” In <i>Proceedings of the Genetic and Evolutionary Computation Conference</i>,
    261–269. GECCO’21. New York, NY, USA: Association for Computing Machinery, 2021.
    <a href="https://doi.org/10.1145/3449639.3459385">https://doi.org/10.1145/3449639.3459385</a>.'
  ieee: 'A. Neumann, J. Bossek, and F. Neumann, “Diversifying Greedy Sampling and
    Evolutionary Diversity Optimisation for Constrained Monotone Submodular Functions,”
    in <i>Proceedings of the Genetic and Evolutionary Computation Conference</i>,
    2021, pp. 261–269, doi: <a href="https://doi.org/10.1145/3449639.3459385">10.1145/3449639.3459385</a>.'
  mla: Neumann, Aneta, et al. “Diversifying Greedy Sampling and Evolutionary Diversity
    Optimisation for Constrained Monotone Submodular Functions.” <i>Proceedings of
    the Genetic and Evolutionary Computation Conference</i>, Association for Computing
    Machinery, 2021, pp. 261–269, doi:<a href="https://doi.org/10.1145/3449639.3459385">10.1145/3449639.3459385</a>.
  short: 'A. Neumann, J. Bossek, F. Neumann, in: Proceedings of the Genetic and Evolutionary
    Computation Conference, Association for Computing Machinery, New York, NY, USA,
    2021, pp. 261–269.'
date_created: 2023-11-14T15:58:59Z
date_updated: 2023-12-13T10:49:25Z
department:
- _id: '819'
doi: 10.1145/3449639.3459385
extern: '1'
keyword:
- evolutionary algorithms
- evolutionary diversity optimisation
- sub-modular functions
language:
- iso: eng
page: 261–269
place: New York, NY, USA
publication: Proceedings of the Genetic and Evolutionary Computation Conference
publication_identifier:
  isbn:
  - 978-1-4503-8350-9
publisher: Association for Computing Machinery
series_title: GECCO’21
status: public
title: Diversifying Greedy Sampling and Evolutionary Diversity Optimisation for Constrained
  Monotone Submodular Functions
type: conference
user_id: '102979'
year: '2021'
...
---
_id: '48892'
abstract:
- lang: eng
  text: Evolutionary algorithms based on edge assembly crossover (EAX) constitute
    some of the best performing incomplete solvers for the well-known traveling salesperson
    problem (TSP). Often, it is desirable to compute not just a single solution for
    a given problem, but a diverse set of high quality solutions from which a decision
    maker can choose one for implementation. Currently, there are only a few approaches
    for computing a diverse solution set for the TSP. Furthermore, almost all of them
    assume that the optimal solution is known. In this paper, we introduce evolutionary
    diversity optimisation (EDO) approaches for the TSP that find a diverse set of
    tours when the optimal tour is known or unknown. We show how to adopt EAX to not
    only find a high-quality solution but also to maximise the diversity of the population.
    The resulting EAX-based EDO approach, termed EAX-EDO is capable of obtaining diverse
    high-quality tours when the optimal solution for the TSP is known or unknown.
    A comparison to existing approaches shows that they are clearly outperformed by
    EAX-EDO.
author:
- first_name: Adel
  full_name: Nikfarjam, Adel
  last_name: Nikfarjam
- first_name: Jakob
  full_name: Bossek, Jakob
  id: '102979'
  last_name: Bossek
  orcid: 0000-0002-4121-4668
- first_name: Aneta
  full_name: Neumann, Aneta
  last_name: Neumann
- first_name: Frank
  full_name: Neumann, Frank
  last_name: Neumann
citation:
  ama: 'Nikfarjam A, Bossek J, Neumann A, Neumann F. Computing Diverse Sets of High
    Quality TSP Tours by EAX-based Evolutionary Diversity Optimisation. In: <i>Proceedings
    of the 16th ACM}/SIGEVO Conference on Foundations of Genetic Algorithms</i>. Association
    for Computing Machinery; 2021:1–11.'
  apa: Nikfarjam, A., Bossek, J., Neumann, A., &#38; Neumann, F. (2021). Computing
    Diverse Sets of High Quality TSP Tours by EAX-based Evolutionary Diversity Optimisation.
    In <i>Proceedings of the 16th ACM}/SIGEVO Conference on Foundations of Genetic
    Algorithms</i> (pp. 1–11). Association for Computing Machinery.
  bibtex: '@inbook{Nikfarjam_Bossek_Neumann_Neumann_2021, place={New York, NY, USA},
    title={Computing Diverse Sets of High Quality TSP Tours by EAX-based Evolutionary
    Diversity Optimisation}, booktitle={Proceedings of the 16th ACM}/SIGEVO Conference
    on Foundations of Genetic Algorithms}, publisher={Association for Computing Machinery},
    author={Nikfarjam, Adel and Bossek, Jakob and Neumann, Aneta and Neumann, Frank},
    year={2021}, pages={1–11} }'
  chicago: 'Nikfarjam, Adel, Jakob Bossek, Aneta Neumann, and Frank Neumann. “Computing
    Diverse Sets of High Quality TSP Tours by EAX-Based Evolutionary Diversity Optimisation.”
    In <i>Proceedings of the 16th ACM}/SIGEVO Conference on Foundations of Genetic
    Algorithms</i>, 1–11. New York, NY, USA: Association for Computing Machinery,
    2021.'
  ieee: 'A. Nikfarjam, J. Bossek, A. Neumann, and F. Neumann, “Computing Diverse Sets
    of High Quality TSP Tours by EAX-based Evolutionary Diversity Optimisation,” in
    <i>Proceedings of the 16th ACM}/SIGEVO Conference on Foundations of Genetic Algorithms</i>,
    New York, NY, USA: Association for Computing Machinery, 2021, pp. 1–11.'
  mla: Nikfarjam, Adel, et al. “Computing Diverse Sets of High Quality TSP Tours by
    EAX-Based Evolutionary Diversity Optimisation.” <i>Proceedings of the 16th ACM}/SIGEVO
    Conference on Foundations of Genetic Algorithms</i>, Association for Computing
    Machinery, 2021, pp. 1–11.
  short: 'A. Nikfarjam, J. Bossek, A. Neumann, F. Neumann, in: Proceedings of the
    16th ACM}/SIGEVO Conference on Foundations of Genetic Algorithms, Association
    for Computing Machinery, New York, NY, USA, 2021, pp. 1–11.'
date_created: 2023-11-14T15:59:00Z
date_updated: 2023-12-13T10:49:59Z
department:
- _id: '819'
extern: '1'
keyword:
- edge assembly crossover (EAX)
- evolutionary algorithms
- evolutionary diversity optimisation (EDO)
- traveling salesperson problem (TSP)
language:
- iso: eng
page: 1–11
place: New York, NY, USA
publication: Proceedings of the 16th ACM}/SIGEVO Conference on Foundations of Genetic
  Algorithms
publication_identifier:
  isbn:
  - 978-1-4503-8352-3
publisher: Association for Computing Machinery
status: public
title: Computing Diverse Sets of High Quality TSP Tours by EAX-based Evolutionary
  Diversity Optimisation
type: book_chapter
user_id: '102979'
year: '2021'
...
