Conference Paper (published)
Under the Hood of Transfer Learning for Deep Neuroevolution
Sarti S, Laurenço N, Adair J, Machado P & Ochoa G (2023) Under the Hood of Transfer Learning for Deep Neuroevolution. In: Applications of Evolutionary Computation. EvoApplications 2023., 12.04.2023-14.04.2023. Springer Nature Switzerland, pp. 640-655. https://doi.org/10.1007/978-3-031-30229-9_41
Article
STNWeb: A new visualization tool for analyzing optimization algorithms
Chacón Sartori C, Blum C & Ochoa G (2023) STNWeb: A new visualization tool for analyzing optimization algorithms. Software Impacts, 17, Art. No.: 100558. https://doi.org/10.1016/j.simpa.2023.100558
Conference Paper (published)
Channel Configuration for Neural Architecture: Insights from the Search Space
Thomson SL, Ochoa G, Veerapen N & Michalak K (2023) Channel Configuration for Neural Architecture: Insights from the Search Space. In: TBC. The Genetic and Evolutionary Computation Conference (GECCO) 2023, Lisbon, Portugal, 15.07.2023-19.07.2023. New York: ACM. https://doi.org/10.1145/nnnnnnn.nnnnnnn
Conference Paper (published)
Randomness in Local Optima Network Sampling
Thomson S, Veerapen N, Ochoa G & van den Berg D (2023) Randomness in Local Optima Network Sampling. In: GECCO ’23 Companion: Genetic and Evolutionary Computation Conference Companion. GECCO '23, Lisbon (hybrid), 15.07.2023-19.07.2023. New York: ACM. https://doi.org/10.1145/3583133.3596309
Conference Paper (published)
On Funnel Depths and Acceptance Criteria in Stochastic Local Search
Thomson S & Ochoa G (2022) On Funnel Depths and Acceptance Criteria in Stochastic Local Search. In: GECCO '22: Proceedings of the Genetic and Evolutionary Computation Conference. Genetic and Evolutionary Computation Conference (GECCO) 2022, Boston, USA, 09.07.2022-13.07.2022. New York: ACM, pp. 287-295. https://dl.acm.org/doi/abs/10.1145/3512290.3528831; https://doi.org/10.1145/3512290.3528831
Conference Paper (published)
Neuroevolution Trajectory Networks of the Behaviour Space
Sarti S, Adair J & Ochoa G (2022) Neuroevolution Trajectory Networks of the Behaviour Space. In: Jiménez Laredo JL, Hidalgo JI & Babaagba KO (eds.) Applications of Evolutionary Computation. Lecture Notes in Computer Science, 13224. EvoApplications 2022, Madrid, Spain, 20.04.2022-22.04.2022. Cham, Switzerland: Springer International Publishing, pp. 685-703. https://doi.org/10.1007/978-3-031-02462-7_43
Conference Paper (published)
Search Trajectories Networks of Multiobjective Evolutionary Algorithms
Lavinas Y, Aranha C & Ochoa G (2022) Search Trajectories Networks of Multiobjective Evolutionary Algorithms. In: Jiménez Laredo JL, Hidalgo JI & Babaagba KO (eds.) Applications of Evolutionary Computation. Lecture Notes in Computer Science, 13224. EvoApplications 2022, Madrid, Spain, 20.04.2022-22.04.2022. Cham, Switzerland: Springer International Publishing, pp. 223-238. https://doi.org/10.1007/978-3-031-02462-7_15
Conference Paper (published)
Fractal Dimension and Perturbation Strength: A Local Optima Networks View
Thomson SL, Ochoa G & Verel S (2022) Fractal Dimension and Perturbation Strength: A Local Optima Networks View. In: Rudolph G, Kononova AV, Aguirre H, Kerschke P, Ochoa G & Tušar T (eds.) Parallel Problem Solving from Nature. Lecture Notes in Computer Science, 13398. Parallel Problem Solving from Nature – PPSN XVII 17th International Conference, PPSN 2022, Dortmund, Germany, 10.09.2022-14.09.2022. Cham, Switzerland: Springer, pp. 562-574. https://doi.org/10.1007/978-3-031-14714-2_39
Article
Goranova M, Ochoa G, Maier P & Hoyle A (2022) Evolutionary optimisation of antibiotic dosing regimens for bacteria with different levels of resistance. Artificial Intelligence in Medicine, 133, Art. No.: 102405. https://doi.org/10.1016/j.artmed.2022.102405
Article
The Fractal Geometry of Fitness Landscapes at the Local Optima Level
Thomson SL, Ochoa G & Verel S (2022) The Fractal Geometry of Fitness Landscapes at the Local Optima Level. Natural Computing, 21 (2), pp. 317-333. https://doi.org/10.1007/s11047-020-09834-y
Article
Recombination and Novelty in Neuroevolution: A Visual Analysis
Sarti S, Adair J & Ochoa G (2022) Recombination and Novelty in Neuroevolution: A Visual Analysis. SN Computer Science, 3 (3), Art. No.: 185. https://doi.org/10.1007/s42979-022-01064-6
Article
Search Trajectory Networks Applied to the Cyclic Bandwidth Sum Problem
Narvaez-Teran V, Ochoa G & Rodriguez-Tello E (2021) Search Trajectory Networks Applied to the Cyclic Bandwidth Sum Problem. IEEE Access, 9, pp. 151266-151277. https://doi.org/10.1109/access.2021.3126015
Article
Dynastic Potential Crossover Operator
Chicano F, Ochoa G, Whitley LD & Tinós R (2021) Dynastic Potential Crossover Operator. Evolutionary Computation. https://doi.org/10.1162/evco_a_00305
Article
Search trajectory networks: A tool for analysing and visualising the behaviour of metaheuristics
Ochoa G, Malan KM & Blum C (2021) Search trajectory networks: A tool for analysing and visualising the behaviour of metaheuristics. Applied Soft Computing, 109, Art. No.: 107492. https://doi.org/10.1016/j.asoc.2021.107492
Conference Paper (published)
Partition crossover for continuous optimization: EPX
Tinós R, Whitley D, Chicano F & Ochoa G (2021) Partition crossover for continuous optimization: EPX. In: Chicano F (ed.) GECCO '21: Proceedings of the Genetic and Evolutionary Computation Conference. 2021 Genetic and Evolutionary Computation Conference, GECCO 2021, Lille, France, 10.07.2021-14.07.2021. New York: Association for Computing Machinery, Inc, pp. 627-635. https://doi.org/10.1145/3449639.3459296
Conference Paper (published)
Cleghorn CW & Ochoa G (2021) Understanding parameter spaces using local optima networks: a case study on particle swarm optimization. In: Chicano F (ed.) GECCO '21: Proceedings of the Genetic and Evolutionary Computation Conference Companion. GECCO '21: Genetic and Evolutionary Computation Conference, Lille, France, 10.07.2021-14.07.2021. New York: ACM, pp. 1657-1664. https://doi.org/10.1145/3449726.3463145
Conference Paper (published)
Real-like MAX-SAT instances and the landscape structure across the phase transition
Chicano F, Ochoa G & Tomassini M (2021) Real-like MAX-SAT instances and the landscape structure across the phase transition. In: Chicano F (ed.) GECCO '21: Proceedings of the Genetic and Evolutionary Computation Conference. 2021 Genetic and Evolutionary Computation Conference, GECCO 2021, Lille, France, 10.07.2021-14.07.2021. New York: Association for Computing Machinery, Inc, pp. 207-215. https://doi.org/10.1145/3449639.3459288
Conference Paper (published)
Local search pivoting rules and the landscape global structure
Tari S & Ochoa G (2021) Local search pivoting rules and the landscape global structure. In: Chicano F (ed.) GECCO '21: Proceedings of the Genetic and Evolutionary Computation Conference. 2021 Genetic and Evolutionary Computation Conference, GECCO 2021, Lille, France, 10.07.2021-14.07.2021. New York: Association for Computing Machinery, Inc, pp. 278-286. https://doi.org/10.1145/3449639.3459295
Article
Duthie AB, Minderman J, Rakotonarivo OS, Ochoa G & Bunnefeld N (2021) Online multiplayer games as virtual laboratories for collecting data on social-ecological decision making. Conservation Biology, 35 (3), pp. 1051-1053. https://doi.org/10.1111/cobi.13633
Article
A Comparative Analysis of Two Matheuristics by Means of Merged Local Optima Networks
Blum C & Ochoa G (2021) A Comparative Analysis of Two Matheuristics by Means of Merged Local Optima Networks. European Journal of Operational Research, 290 (1), pp. 36-56. https://doi.org/10.1016/j.ejor.2020.08.008
Conference Paper (published)
A NEAT Visualisation of Neuroevolution Trajectories
Sarti S & Ochoa G (2021) A NEAT Visualisation of Neuroevolution Trajectories. In: Castillo PA & Jiménez Laredo JL (eds.) Applications of Evolutionary Computation. Lecture Notes in Computer Science, 12694. 24th International Conference, EvoApplications 2021, Seville, Spain, 07.04.2021-09.04.2021. Cham, Switzerland: Springer, pp. 714-728. https://doi.org/10.1007/978-3-030-72699-7_45
Conference Paper (published)
Synthetic vs. Real-World Continuous Landscapes: A Local Optima Networks View
Contreras-Cruz MA, Ochoa G & Ramirez-Paredes JP (2020) Synthetic vs. Real-World Continuous Landscapes: A Local Optima Networks View. In: Filipič B, Minisci E & Vasile M (eds.) Bioinspired Optimization Methods and Their Applications. Lecture Notes in Computer Science, 12438. 9th International Conference, BIOMA 2020, Brussels, Belgium, 19.11.2020-20.11.2020. Cham, Switzerland: Springer International Publishing, pp. 3-16. https://doi.org/10.1007/978-3-030-63710-1_1
Article
Optimising efficacy of antibiotics against systemic infection by varying dosage quantities and times
Hoyle A, Cairns D, Paterson I, McMillan S, Ochoa G & Desbois AP (2020) Optimising efficacy of antibiotics against systemic infection by varying dosage quantities and times. PLoS Computational Biology, 16 (8), Art. No.: e1008037. https://doi.org/10.1371/journal.pcbi.1008037
Conference Paper (published)
Optimising Antibiotic Treatments with Multi-objective Population-based Algorithms
Goranova M, Contreras-Cruz MA, Hoyle A & Ochoa G (2020) Optimising Antibiotic Treatments with Multi-objective Population-based Algorithms. In: CEC 2020: Congress on Evolutionary Computation. 2020 IEEE Congress on Evolutionary Computation (CEC), Glasgow, United Kingdom, 19.07.2020-24.07.2020. Piscataway, NJ, USA: IEEE. https://doi.org/10.1109/cec48606.2020.9185489
Conference Paper (published)
Global Landscape Structure and the Random MAX-SAT Phase Transition
Ochoa G, Chicano F & Tomassini M (2020) Global Landscape Structure and the Random MAX-SAT Phase Transition. In: Bäck T, Preuss M, Deutz A, Wang H, Doerr C, Emmerich M & Trautmann H (eds.) Parallel Problem Solving from Nature. Lecture Notes in Computer Science. PPSN 2020: Conference on Parallel Problem Solving from Nature, Leiden, The Netherlands, 05.09.2020-09.09.2020. Cham, Switzerland: Springer International Publishing, pp. 125-138. https://doi.org/10.1007/978-3-030-58115-2_9
Article
A Methodology for Classifying Search Operators as Intensification or Diversification Heuristics
Soria-Alcaraz JA, Ochoa G, Espinal A, Sotelo-Figueroa MA, Ornelas-Rodriguez M & Rostro-Gonzalez H (2020) A Methodology for Classifying Search Operators as Intensification or Diversification Heuristics. Complexity, 2020 p. 10, Art. No.: 2871835. https://doi.org/10.1155/2020/2871835
Article
Inferring Future Landscapes: Sampling the Local Optima Level
Thomson SL, Ochoa G, Verel S & Veerapen N (2020) Inferring Future Landscapes: Sampling the Local Optima Level. Evolutionary Computation, 28 (4), pp. 621-641. https://doi.org/10.1162/evco_a_00271
Conference Paper (published)
The Local Optima Level in Chemotherapy Schedule Optimisation
Thomson SL & Ochoa G (2020) The Local Optima Level in Chemotherapy Schedule Optimisation. In: Zarges C & Paquete L (eds.) Evolutionary Computation in Combinatorial Optimization. EvoCOP 2020. Lecture Notes in Computer Science, 12102. EvoCOP 2020: European Conference on Evolutionary Computation in Combinatorial Optimization, Seville, Spain, 15.04.2020-17.04.2020. Cham, Switzerland: Springer, pp. 197-213. https://doi.org/10.1007/978-3-030-43680-3_13
Conference Paper (published)
Search Trajectory Networks of Population-based Algorithms in Continuous Spaces
Ochoa G, Malan KM & Blum C (2020) Search Trajectory Networks of Population-based Algorithms in Continuous Spaces. In: Castillo PA, Jiménez Laredo JL & Fernández de Vega F (eds.) Applications of Evolutionary Computation. EvoApplications 2020. Lecture Notes in Computer Science, 12104. Applications of Evolutionary Computation – 23rd International Conference, EvoApplications 2020, Seville, Spain, 15.04.2020-17.04.2020. Cham, Switzerland: Springer, pp. 70-85. https://doi.org/10.1007/978-3-030-43722-0_5
Conference Paper (published)
Fitness Landscape Analysis of Automated Machine Learning Search Spaces
Pimenta CG, de Sá AGC, Ochoa G & Pappa GL (2020) Fitness Landscape Analysis of Automated Machine Learning Search Spaces. In: Paquete L & Zarges C (eds.) Evolutionary Computation in Combinatorial Optimization. EvoCOP 2020. Lecture Notes in Computer Science, 12102. EvoCOP 2020: Evolutionary Computation in Combinatorial Optimization, Seville, Spain, 15.04.2020-17.04.2020. Cham, Switzerland: Springer International Publishing, pp. 114-130. https://doi.org/10.1007/978-3-030-43680-3_8
Article
Tinós R, Whitley D & Ochoa G (2020) A New Generalized Partition Crossover for the Traveling Salesman Problem: Tunneling Between Local Optima. Evolutionary Computation, 28 (2), pp. 255-288. https://doi.org/10.1162/evco_a_00254
Article
Multi-objective Evolutionary Design of Antibiotic Treatments
Ochoa G, Christie LA, Brownlee AE & Hoyle A (2020) Multi-objective Evolutionary Design of Antibiotic Treatments. Artificial Intelligence in Medicine, 102, Art. No.: 101759. https://doi.org/10.1016/j.artmed.2019.101759
Conference Paper (published)
Insights into the feature selection problem using local optima networks
Mostert W, Malan KM, Ochoa G & Engelbrecht AP (2019) Insights into the feature selection problem using local optima networks. In: Liefooghe A & Paquete L (eds.) Evolutionary Computation in Combinatorial Optimization. Lecture Notes in Computer Science, 11452. 19th European Conference on Evolutionary Computation in Combinatorial Optimization, EvoCOP 2019, held as part of EvoStar 2019, Leipzig, Germany, 24.04.2019-26.04.2019. Cham, Switzerland: Springer Verlag, pp. 147-162. https://doi.org/10.1007/978-3-030-16711-0_10
Conference Paper (published)
Clarifying the Difference in Local Optima Network Sampling Algorithms
Thomson SL, Ochoa G & Verel S (2019) Clarifying the Difference in Local Optima Network Sampling Algorithms. In: Liefooghe A & Paquete L (eds.) Evolutionary Computation in Combinatorial Optimization. Lecture Notes in Computer Science, 11452. The 19th European Conference on Evolutionary Computation in Combinatorial Optimisation, Leipzig, Germany, 24.04.2019-26.04.2019. Cham, Switzerland: Springer International Publishing, pp. 163-178. https://doi.org/10.1007/978-3-030-16711-0_11
Conference Paper (published)
Local Optima Networks for Continuous Fitness Landscapes
Adair J, Ochoa G & Malan KM (2019) Local Optima Networks for Continuous Fitness Landscapes. In: López-Ibáñez M (ed.) GECCO '19: Proceedings of the Genetic and Evolutionary Computation Conference Companion. GECCO '19 - Genetic and Evolutionary Computation Conference, Prague, Czech Republic, 13.07.2019-17.07.2019. New York: Association for Computing Machinery, pp. 1407-1414. https://doi.org/10.1145/3319619.3326852
Conference Paper (published)
Local Optima Network Analysis for MAX-SAT
Ochoa G & Chicano F (2019) Local Optima Network Analysis for MAX-SAT. In: López-Ibáñez M (ed.) GECCO '19: Proceedings of the Genetic and Evolutionary Computation Conference Companion. GECCO '19 - Genetic and Evolutionary Computation Conference, Prague, Czech Republic, 13.07.2019-17.07.2019. New York: Association for Computing Machinery, pp. 1430-1437. https://doi.org/10.1145/3319619.3326855
Conference Paper (published)
Recent Advances in Fitness Landscape Analysis
Ochoa G & Malan K (2019) Recent Advances in Fitness Landscape Analysis. In: López-Ibáñez M (ed.) GECCO '19: Proceedings of the Genetic and Evolutionary Computation Conference Companion. GECCO '19 - Genetic and Evolutionary Computation Conference, Prague, Czech Republic, 13.07.2019-17.07.2019. New York: Association for Computing Machinery, pp. 1077-1094. https://doi.org/10.1145/3319619.3323383
Conference Paper (published)
Rigorous Performance Analysis of State-of-the-Art TSP Heuristic Solvers
McMenemy P, Veerapen N, Adair J & Ochoa G (2019) Rigorous Performance Analysis of State-of-the-Art TSP Heuristic Solvers. In: Liefooghe A & Paquete L (eds.) Evolutionary Computation in Combinatorial Optimization. Lecture Notes in Computer Science, 11452. EVOCOP 2019: European Conference on Evolutionary Computation in Combinatorial Optimization, Leipzig, Germany, 24.04.2019-26.04.2019. Cham, Switzerland: Springer International Publishing, pp. 99-114. https://doi.org/10.1007/978-3-030-16711-0_7
Conference Paper (published)
Quasi-Optimal Recombination Operator
Chicano F, Ochoa G, Whitley D & Tinós R (2019) Quasi-Optimal Recombination Operator. In: Liefooghe A & Paquete L (eds.) Evolutionary Computation in Combinatorial Optimization. Lecture Notes in Computer Science, 11452. EvoCOP 2019: European Conference on Evolutionary Computation in Combinatorial Optimization, Leipzig, Germany, 24.04.2019-26.04.2019. Cham, Switzerland: Springer International Publishing, pp. 131-146. https://doi.org/10.1007/978-3-030-16711-0_9
Article
Google Trends in Infodemiology and Infoveillance: Methodology Framework
Mavragani A & Ochoa G (2019) Google Trends in Infodemiology and Infoveillance: Methodology Framework. JMIR Public Health and Surveillance, 5 (2), Art. No.: e13439. https://doi.org/10.2196/13439
Article
Infoveillance of infectious diseases in USA: STDs, tuberculosis, and hepatitis
Mavragani A & Ochoa G (2018) Infoveillance of infectious diseases in USA: STDs, tuberculosis, and hepatitis. Journal of Big Data, 5 (1), Art. No.: 30. https://doi.org/10.1186/s40537-018-0140-9
Conference Paper (published)
Perturbation strength and the global structure of qap fitness landscapes
Ochoa G & Herrmann S (2018) Perturbation strength and the global structure of qap fitness landscapes. In: Fonseca C, Lourenco N, Machado P, Paquete L, Auger A & Whitley D (eds.) Parallel Problem Solving from Nature – PPSN XV. PPSN 2018. Lecture Notes in Computer Science, 11102. PPSN 2018: International Conference on Parallel Problem Solving from Nature, Coimbra, Portugal, 08.09.2018-12.09.2018. Cham, Switzerland: Springer Verlag, pp. 245-256. https://doi.org/10.1007/978-3-319-99259-4_20
Conference Paper (published)
Sampling local optima networks of large combinatorial search spaces: The qap case
Verel S, Daolio F, Ochoa G & Tomassini M (2018) Sampling local optima networks of large combinatorial search spaces: The qap case. In: Fonseca C, Lourenco N, Machado P, Paquete L, Auger A & Whitley D (eds.) Parallel Problem Solving from Nature – PPSN XV. PPSN 2018. Lecture Notes in Computer Science, 11102. PPSN 2018: International Conference on Parallel Problem Solving from Nature, Coimbra, Portugal, 08.09.2018-12.09.2018. Cham, Switzerland: Springer Verlag, pp. 257-268. https://doi.org/10.1007/978-3-319-99259-4_21
Conference Paper (published)
Multifractality and Dimensional Determinism in Local Optima Networks
Thomson S, Verel S, Ochoa G, Veerapen N & Cairns D (2018) Multifractality and Dimensional Determinism in Local Optima Networks. In: Proceedings of the Genetic and Evolutionary Computation Conference 2018. 2018 Genetic and Evolutionary Computation Conference (GECCO 2018), Kyoto, Japan, 15.07.2018-19.07.2018. New York: ACM, pp. 371-378. http://gecco-2018.sigevo.org; https://doi.org/10.1145/3205455.3205472
Conference Paper (published)
On the Fractal Nature of Local Optima Networks
Thomson SL, Verel S, Ochoa G, Veerapen N & McMenemy P (2018) On the Fractal Nature of Local Optima Networks. In: Liefooghe A & López-Ibáñez M (eds.) Evolutionary Computation in Combinatorial Optimization. EvoCOP 2018.. Lecture Notes in Computer Science, 10782. EvoCOP 2018 - The 18th European Conference on Evolutionary Computation in Combinatorial Optimisation, Parma, Italy, 04.04.2018-06.04.2018. Cham, Switzerland: Springer, pp. 18-33. https://doi.org/10.1007/978-3-319-77449-7_2
Conference Paper (published)
How Perturbation Strength Shapes the Global Structure of TSP Fitness Landscapes
McMenemy P, Veerapen N & Ochoa G (2018) How Perturbation Strength Shapes the Global Structure of TSP Fitness Landscapes. In: Liefooghe A & López-Ibáñez M (eds.) Evolutionary Computation in Combinatorial Optimization. EvoCOP 2018. Lecture Notes in Computer Science, 10782. EvoCOP 2018 - The 18th European Conference on Evolutionary Computation in Combinatorial Optimisation, Parma, Italy, 04.04.2018-06.04.2018. Cham, Switzerland: Springer, pp. 34-49. https://doi.org/10.1007/978-3-319-77449-7_3
Article
Forecasting AIDS prevalence in the United States using online search traffic data
Mavragani A & Ochoa G (2018) Forecasting AIDS prevalence in the United States using online search traffic data. Journal of Big Data, 5 (1), Art. No.: 17. https://doi.org/10.1186/s40537-018-0126-7
Conference Paper (published)
Evolving training sets for improved transfer learning in brain computer interfaces
Adair J, Brownlee A, Daolio F & Ochoa G (2018) Evolving training sets for improved transfer learning in brain computer interfaces. In: Nicosia G, Pardalos P, Giuffrida G & Umeton R (eds.) Machine Learning, Optimization, and Big Data. MOD 2017. Lecture Notes in Computer Science, 10710. MOD 2017 - The Third International Conference on Machine Learning, Optimization and Big Data, Volterra, Italy, 14.09.2017-17.09.2017. Cham, Switzerland: Springer, pp. 186-197. https://link.springer.com/chapter/10.1007/978-3-319-72926-8_16; https://doi.org/10.1007/978-3-319-72926-8_16
Conference Paper (published)
Adair J, Brownlee A & Ochoa G (2018) Mutual Information Iterated Local Search: A Wrapper-Filter Hybrid for Feature Selection in Brain Computer Interfaces. In: Applications of Evolutionary Computation. EvoApplications 2018. Lecture Notes in Computer Science, 10784. EvoStar 2018, Parma, Italy, 04.04.2018-06.04.2018. Cham, Switzerland: Springer, pp. 63-77. https://link.springer.com/chapter/10.1007/978-3-319-77538-8_5; https://doi.org/10.1007/978-3-319-77538-8_5
Article
Mavragani A, Ochoa G & Tsagarakis KP (2018) Assessing the Methods, Tools, and Statistical Approaches in Google Trends Research: Systematic Review. JMIR, 20 (11), Art. No.: e270. https://doi.org/10.2196/jmir.9366
Article
Visualising the Global Structure of Search Landscapes: Genetic Improvement as a Case Study
Veerapen N & Ochoa G (2018) Visualising the Global Structure of Search Landscapes: Genetic Improvement as a Case Study. Genetic Programming and Evolvable Machines, 19 (3, Special Issue: SI), pp. 317-349. https://doi.org/10.1007/s10710-018-9328-1
Article
Mapping the global structure of TSP fitness landscapes
Ochoa G & Veerapen N (2018) Mapping the global structure of TSP fitness landscapes. Journal of Heuristics, 24 (3), pp. 265-294. https://doi.org/10.1007/s10732-017-9334-0
Article
An Empirical Study of Meta- and Hyper-Heuristic Search for Multi-Objective Release Planning
Zhang Y, Harman M, Ochoa G, Ruhe G & Brinkkemper S (2018) An Empirical Study of Meta- and Hyper-Heuristic Search for Multi-Objective Release Planning. ACM Transactions on Software Engineering and Methodology, 27 (1), Art. No.: 3. https://doi.org/10.1145/3196831
Article
PageRank centrality for performance prediction: the impact of the local optima network model
Herrmann S, Ochoa G & Rothlauf F (2018) PageRank centrality for performance prediction: the impact of the local optima network model. Journal of Heuristics, 24 (3), pp. 243-264. https://doi.org/10.1007/s10732-017-9333-1
Article
The Internet and the Anti-Vaccine Movement: Tracking the 2017 EU Measles Outbreak
Mavragani A & Ochoa G (2018) The Internet and the Anti-Vaccine Movement: Tracking the 2017 EU Measles Outbreak. Big Data and Cognitive Computing, 2 (1), Art. No.: 2. https://doi.org/10.3390/bdcc2010002
Book Chapter
Iterated VND Versus Hyper-heuristics: Effective and General Approaches to Course Timetabling
Soria-Alcaraz JA, Ochoa G, Sotelo-Figeroa M, Carpio M & Puga H (2017) Iterated VND Versus Hyper-heuristics: Effective and General Approaches to Course Timetabling. In: Melin P, Castillo O & Kacprzyk J (eds.) Nature-Inspired Design of Hybrid Intelligent Systems. Studies in Computational Intelligence, 667. Cham, Switzerland: Springer, pp. 687-700. https://link.springer.com/chapter/10.1007/978-3-319-47054-2_45; https://doi.org/10.1007/978-3-319-47054-2_45
Conference Paper (published)
Shaping communities of local optima by perturbation strength
Herrmann S, Herrmann M, Ochoa G & Rothlauf F (2017) Shaping communities of local optima by perturbation strength. In: GECCO '17: Proceedings of the Genetic and Evolutionary Computation Conference. GECCO 2017: Genetic and Evolutionary Computation Conference, Berlin, Germany, 15.07.2017-19.07.2017. New York: ACM, pp. 266-273. https://doi.org/10.1145/3071178.3071243
Conference Paper (published)
Chicano F, Whitley D, Ochoa G & Tinós R (2017) Optimizing one million variable NK landscapes by hybridizing deterministic recombination and local search. In: GECCO '17: Proceedings of the Genetic and Evolutionary Computation Conference. GECCO 2017: The Genetic and Evolutionary Computation Conference, Berlin, Germany, 15.07.2017-19.07.2017. New York: ACM, pp. 753-760. https://doi.org/10.1145/3071178.3071285
Conference Paper (published)
Modelling Genetic Improvement Landscapes with Local Optima Networks
Veerapen N, Daolio F & Ochoa G (2017) Modelling Genetic Improvement Landscapes with Local Optima Networks. In: Proceedings of GECCO '17 Conference Companion. Genetic Improvement Workshop 2017, Berlin, Germany, 15.07.2017-15.07.2017. New York: ACM, pp. 1543-1548. http://dx.doi.org/10.1145/3067695.3082518; https://doi.org/10.1145/3067695.3082518
Conference Paper (published)
The Effect of Landscape Funnels in QAPLIB Instances
Thomson S, Ochoa G, Daolio F & Veerapen N (2017) The Effect of Landscape Funnels in QAPLIB Instances. In: Proceedings of the Genetic and Evolutionary Computation Conference Companion 2017, Berlin, Germany, July 15–19, 2017 (GECCO ’17). GECCO ’17: The Genetic and Evolutionary Computation Conference, Berlin, Germany, 15.07.2017-19.07.2017. New York: ACM, pp. 1495-1500. https://doi.org/10.1145/3067695.3082512
Conference Paper (published)
Comparing Communities of Optima with Funnels in Combinatorial Fitness Landscapes
Thomson S, Daolio F & Ochoa G (2017) Comparing Communities of Optima with Funnels in Combinatorial Fitness Landscapes. In: Proceedings of the Genetic and Evolutionary Computation Conference 2017, Berlin, Germany, July 15–19, 2017 (GECCO ’17). GECCO ’17: The Genetic and Evolutionary Computation Conference, Berlin, Germany, 15.07.2017-19.07.2017. New York: ACM, pp. 377-384. https://doi.org/10.1145/3071178.3071211
Conference Paper (published)
Visualising the Search Landscape of the Triangle Program
Langdon WB, Veerapen N & Ochoa G (2017) Visualising the Search Landscape of the Triangle Program. In: McDermott J, Castelli M, Sekanina L, Haasdijk E & García-Sánchez P (eds.) EuroGP 2017: Genetic Programming. Lecture Notes in Computer Science, 10196. The 20th European Conference on Genetic Programming (EuroGP), Amsterdam, The Netherlands, 19.04.2017-21.04.2017. Cham, Switzerland: Springer, pp. 96-113. https://doi.org/10.1007/978-3-319-55696-3_7
Article
A methodology for determining an effective subset of heuristics in selection hyper-heuristics
Soria-Alcaraz JA, Ochoa G, Sotelo-Figeroa M & Burke EK (2017) A methodology for determining an effective subset of heuristics in selection hyper-heuristics. European Journal of Operational Research, 260 (3), pp. 972-983. https://doi.org/10.1016/j.ejor.2017.01.042
Conference Paper (published)
Local Optima Networks for the Permutation Flowshop Scheduling Problem: Makespan vs. Total Flow Time
Hernando L, Daolio F, Veerapen N & Ochoa G (2017) Local Optima Networks for the Permutation Flowshop Scheduling Problem: Makespan vs. Total Flow Time. In: 2017 IEEE Congress on Evolutionary Computation (CEC). IEEE Congress on Evolutionary Computation 2017, San Sebastián, Spain, 05.06.2017-08.06.2017. Piscataway, NJ, USA: IEEE, pp. 1964-1971. https://doi.org/10.1109/CEC.2017.7969541
Conference Paper (published)
Understanding Phase Transitions with Local Optima Networks: Number Partitioning as a Case Study
Ochoa G, Veerapen N, Daolio F & Tomassini M (2017) Understanding Phase Transitions with Local Optima Networks: Number Partitioning as a Case Study. In: Bin H & Lopez-Ibanez M (eds.) Evolutionary Computation in Combinatorial Optimization. EvoCOP 2017. Lecture Notes in Computer Science, 10197. 17th European Conference on Evolutionary Computation in Combinatorial Optimisation (EvoCOP), Amsterdam, The Netherlands, 19.04.2017-21.04.2017. Cham, Switzerland: Springer. https://doi.org/10.1007/978-3-319-55453-2_16
Conference Paper (published)
An Evolutionary Hyper-heuristic for the Software Project Scheduling Problem
Wu X, Consoli P, Minku L, Ochoa G & Yao X (2016) An Evolutionary Hyper-heuristic for the Software Project Scheduling Problem. In: Handl J, Hart E, Lewis P, Lopez-Ibanez M, Ochoa G & Paechter B (eds.) Parallel Problem Solving from Nature - PPSN XIV. Lecture Notes in Computer Science, 9921. International Conference on Parallel Problem Solving from Nature 2016: PPSN XIV, Edinburgh, 17.09.2016-21.09.2017. Cham, Switzerland: Springer Verlag, pp. 37-47. https://doi.org/10.1007/978-3-319-45823-6_4
Conference Paper (published)
Coarse-Grained Barrier Trees of Fitness Landscapes
Herrmann S, Ochoa G & Rothlauf F (2016) Coarse-Grained Barrier Trees of Fitness Landscapes. In: Handl J, Hart E, Lewis P, LopezIbanez M, Ochoa G & Paechter B (eds.) Parallel Problem Solving from Nature – PPSN XIV. PPSN 2016. Lecture Notes in Computer Science, 9921. PPSN2016: 14th International Conference on Parallel Problem Solving from Nature, Edinburgh, 17.09.2016-21.09.2016. Cham: Springer, pp. 901-910. https://doi.org/10.1007/978-3-319-45823-6_84
Article
Editorial for the Special Issue on Combinatorial Optimization Problems
Chicano F, Blum C & Ochoa G (2016) Editorial for the Special Issue on Combinatorial Optimization Problems. Evolutionary Computation, 24 (4), pp. 573-575. https://doi.org/10.1162/EVCO_e_00192
Conference Paper (published)
Additional Dimensions to the Study of Funnels in Combinatorial Landscapes
Ochoa G & Veerapen N (2016) Additional Dimensions to the Study of Funnels in Combinatorial Landscapes. In: GECCO '16 Proceedings of the 2016 Genetic and Evolutionary Computation Conference 2016. The 2016 Genetic and Evolutionary Computation Conference (GECCO 2016), Denver, Colorado, USA, 20.07.2016-24.07.2016. New York, NY, USA: ACM, pp. 373-380. http://dl.acm.org/citation.cfm?id=2908820&CFID=827599008&CFTOKEN=74602334; https://doi.org/10.1145/2908812.2908820
Conference Paper (published)
The Multi-Funnel Structure of TSP Fitness Landscapes: A Visual Exploration
Ochoa G, Veerapen N, Whitley D & Burke E (2016) The Multi-Funnel Structure of TSP Fitness Landscapes: A Visual Exploration. In: Bonnevay S, Legrand P, Monmarché N, Lutton E & Schoenauer M (eds.) Artificial Evolution: 12th International Conference, Evolution Artificielle, EA 2015, Lyon, France, October 26-28, 2015. Revised Selected Papers. Lecture Notes in Computer Science, 9554. International Conference on Artificial Evolution (EA-2015), Lyon, France, 26.10.2015-28.10.2015. Cham, Switzerland: Springer, pp. 1-13. https://doi.org/10.1007/978-3-319-31471-6_1
Article
Optimising Antibiotic Usage to Treat Bacterial Infections
Paterson IK, Hoyle A, Ochoa G, Baker-Austin C & Taylor NGH (2016) Optimising Antibiotic Usage to Treat Bacterial Infections. Scientific Reports, 6, Art. No.: 37853. https://doi.org/10.1038/srep37853
Conference Paper (published)
Genetic improvement: A key challenge for evolutionary computation
Langdon WB & Ochoa G (2016) Genetic improvement: A key challenge for evolutionary computation. In: 2016 IEEE Congress on Evolutionary Computation, CEC 2016. 2016 IEEE Congress on Evolutionary Computation (CEC), Vancouver, Canada, 24.07.2016-29.07.2016. Piscataway, NJ, USA: IEEE, pp. 3068-3075. https://doi.org/10.1109/CEC.2016.7744177
Conference Paper (published)
Evolutionary Algorithms with Linkage Information for Feature Selection in Brain Computer Interfaces
Adair J, Brownlee A & Ochoa G (2016) Evolutionary Algorithms with Linkage Information for Feature Selection in Brain Computer Interfaces. In: Angelov P, Gegov A, Jayne C & Shen Q (eds.) Advances in Computational Intelligence Systems: Contributions Presented at the 16th UK Workshop on Computational Intelligence, September 7–9, 2016, Lancaster, UK. Advances in Intelligent Systems and Computing, 513. UKCI 2016 - 16th UK Workshop on Computational Intelligence, Lancaster, 07.09.2016-09.09.2016. London: Springer, pp. 287-307. https://doi.org/10.1007/978-3-319-46562-3_19
Conference Paper (published)
Tunnelling Crossover Networks for the Asymmetric TSP
Veerapen N, Ochoa G, Tinós R & Whitley D (2016) Tunnelling Crossover Networks for the Asymmetric TSP. In: Handl J, Hart E, Lewis P, Lopez-Ibanez M, Ochoa G & Paechter B (eds.) Parallel Problem Solving from Nature – PPSN XIV: 14th International Conference, Edinburgh, UK, September 17-21, 2016, Proceedings. Lecture Notes in Computer Science, 9921. PPSN2016 - 14th International Conference on Parallel Problem Solving from Nature, Edinburgh, 17.09.2016-21.09.2016. Cham, Switzerland: Springer, pp. 994-1003. https://doi.org/10.1007/978-3-319-45823-6_93
Conference Paper (published)
Communities of Local Optima as Funnels in Fitness Landscapes
Herrmann S, Ochoa G & Rothlauf F (2016) Communities of Local Optima as Funnels in Fitness Landscapes. In: Friedrich T (ed.) Proceedings of the 2016 on Genetic and Evolutionary Computation Conference, Denver, CO, USA, July 20 - 24, 2016. GECCO 16: Genetic and Evolutionary Computation Conference 2016, Denver, CO, USA, 20.07.2016-24.07.2016. New York: ACM, pp. 325-331. https://doi.org/10.1145/2908812.2908818
Article
Grammar-based generation of variable-selection heuristics for constraint satisfaction problems
Sosa-Ascencio A, Ochoa G, Terashima-Marin H & Conant-Pablos SE (2016) Grammar-based generation of variable-selection heuristics for constraint satisfaction problems. Genetic Programming and Evolvable Machines, 17 (2), pp. 119--144. https://doi.org/10.1007/s10710-015-9249-1
Conference Paper (published)
Deconstructing the Big Valley Search Space Hypothesis
Ochoa G & Veerapen N (2016) Deconstructing the Big Valley Search Space Hypothesis. In: Chicano F, Hu B & García-Sánchez P (eds.) Evolutionary Computation in Combinatorial Optimization: 16th European Conference, EvoCOP 2016, Porto, Portugal, March 30 -- April 1, 2016, Proceedings. Lecture Notes in Computer Science, 9595. 16th European Conference on Evolutionary Computation in Combinatorial Optimisation, EvoCOP 2016, Porto, Portugal, 30.03.2016-01.04.2016. Cham, Switzerland: Springer International Publishing, pp. 58-73. http://link.springer.com/chapter/10.1007%2F978-3-319-30698-8_5; https://doi.org/10.1007/978-3-319-30698-8_5
Article
An Integer Linear Programming approach to the single and bi-objective Next Release Problem
Veerapen N, Ochoa G, Harman M & Burke E (2015) An Integer Linear Programming approach to the single and bi-objective Next Release Problem. Information and Software Technology, 65, pp. 1-13. https://doi.org/10.1016/j.infsof.2015.03.008
Book Chapter
Ochoa G, Verel S, Daolio F & Tomassini M (2014) Local Optima Networks: A New Model of Combinatorial Fitness Landscapes, Recent Advances in the Theory and Application of Fitness Landscapes. In: Richter H & Engelbrecht A (eds.) Recent Advances in the Theory and Application of Fitness Landscapes, Part II. Emergence, Complexity and Computation, 6. Berlin Heidelberg: Springer, pp. 233-262. http://link.springer.com/chapter/10.1007/978-3-642-41888-4_9
Article
A unified hyper-heuristic framework for solving bin packing problems
Lopez-Camacho E, Terashima-Marin H, Ross P & Ochoa G (2014) A unified hyper-heuristic framework for solving bin packing problems. Expert Systems with Applications, 41 (15), pp. 6876-6889. https://doi.org/10.1016/j.eswa.2014.04.043
Article
Effective learning hyper-heuristics for the course timetabling problem
Soria-Alcaraz JA, Ochoa G, Swan J, Carpio M, Puga H & Burke E (2014) Effective learning hyper-heuristics for the course timetabling problem. European Journal of Operational Research, 238 (1), pp. 77-86. https://doi.org/10.1016/j.ejor.2014.03.046
Article
The component model for elementary landscapes and partial neighborhoods
Whitley D, Sutton AM, Ochoa G & Chicano F (2014) The component model for elementary landscapes and partial neighborhoods. Theoretical Computer Science, 545 p. 75. https://doi.org/10.1016/j.tcs.2014.04.036
Article
Contrasting meta-learning and hyper-heuristic research: the role of evolutionary algorithms
Pappa GL, Ochoa G, Hyde M, Freitas AA, Woodward J & Swan J (2014) Contrasting meta-learning and hyper-heuristic research: the role of evolutionary algorithms. Genetic Programming and Evolvable Machines, 15 (1), pp. 3-35. https://doi.org/10.1007/s10710-013-9186-9
Conference Paper (published)
Local Optima Networks of the Permutation flow-shop Problem
Daolio F, Verel S, Ochoa G & Tomassini M (2013) Local Optima Networks of the Permutation flow-shop Problem. In: Legrand P, Corsini M, Hao J, Monmarche N, Collet P, Lutton E & Schoenauer M (eds.) Arti cial Evolution 2013 (Evolution Arti cielle 2013): 11th Biennal International Conference on Arti cial Evolution Proceedings. Articial Evolution 2013 (Evolution Articielle 2013): 11th Biennal International Conference on Articial Evolution, Bordeaux, France, 21.10.2013-23.10.2013, pp. 200-212. http://ea2013.inria.fr//proceedings.pdf
Conference Paper (published)
Search methodologies in real-world software engineering
Ochoa G (2013) Search methodologies in real-world software engineering. In: GECCO '13 Companion: Proceeding of the fifteenth annual conference on Genetic and evolutionary computation conference companion. GECCO '13 Fifteenth annual conference on Genetic and evolutionary computation, Amsterdam, The Netherlands, 06.07.2013-10.07.2013. New York, NY, USA: ACM, pp. 1085-1087. http://dl.acm.org/citation.cfm?id=2482687; https://doi.org/10.1145/2464576.2482687
Article
Understanding the structure of bin packing problems through principal component analysis
Lopez-Camacho E, Terashima-Marin H, Ochoa G & Conant-Pablos SE (2013) Understanding the structure of bin packing problems through principal component analysis. International Journal of Production Economics, 145 (2), pp. 488-499. https://doi.org/10.1016/j.ijpe.2013.04.041
Article
Hyper-heuristics: A survey of the state of the art
Burke E, Gendreau M, Hyde M, Kendall G, Ochoa G, Ozcan E & Qu R (2013) Hyper-heuristics: A survey of the state of the art. Journal of the Operational Research Society, 64 (12), pp. 1695-1724. https://doi.org/10.1057/jors.2013.71
Article
An effective heuristic for the two-dimensional irregular bin packing problem
Lopez-Camacho E, Ochoa G, Terashima-Marin H & Burke E (2013) An effective heuristic for the two-dimensional irregular bin packing problem. Annals of Operations Research, 206 (1), pp. 241-264. https://doi.org/10.1007/s10479-013-1341-4
Article
Population-based optimization of cytostatic/cytotoxic combination cancer chemotherapy
Ochoa G & Villasana M (2013) Population-based optimization of cytostatic/cytotoxic combination cancer chemotherapy. Soft Computing, 17 (6), pp. 913-924. https://doi.org/10.1007/s00500-013-1043-5
Conference Paper (published)
Vehicle routing and adaptive iterated local search within the HyFlex hyper-heuristic framework
Walker J, Ochoa G, Gendreau M & Burke E (2012) Vehicle routing and adaptive iterated local search within the HyFlex hyper-heuristic framework. In: Hamadi Y & Schoenauer M (eds.) Learning and Intelligent Optimization 6th International Conference, LION 6, Paris, France, January 16-20, 2012, Revised Selected Papers. Lecture Notes in Computer Science, Vol. 7219. 6th International Conference, LION 6,, Paris, France, 16.01.2012-20.01.2012. Amsterdam: Springer, pp. 265-276. http://link.springer.com/chapter/10.1007/978-3-642-34413-8_19#; https://doi.org/10.1007/978-3-642-34413-8_19
Conference Paper (published)
Generic Software Subgraph Isomorphism
Swan J, Harman M, Ochoa G & Burke E (2012) Generic Software Subgraph Isomorphism. In: 4th Symposium on Search Based-Software Engineering, Riva del Garda, Trento, Italy, September 28th-30th 2012: Fast Abstracts. 4th Symposium on Search Based Software Engineering (4th SSBSE). Trento, Italy: Fondazione Bruno Kessler Press, pp. 43-48. http://selab.fbk.eu/ssbse2012/index.php?p=program
Conference Paper (published)
Local optima networks with escape edges
Verel S, Daolio F, Ochoa G & Tomassini M (2012) Local optima networks with escape edges. In: Hao J, Legrand P, Collet P, Monmarche N, Lutton E & Schoenauer M (eds.) Artificial Evolution: 10th International Conference, Evolution Artificielle, EA 2011, Angers, France, October 24-26, 2011, Revised Selected Papers. Lecture Notes in Computer Science, 7401. EA 2011 - 10th International Conference on Artificial Evolution/Evolution Artificielle, Angers, France, 24.10.2011-26.10.2011. Berin Heidelberg: Springer, pp. 49-60. http://link.springer.com/chapter/10.1007/978-3-642-35533-2_5#; https://doi.org/10.1007/978-3-642-35533-2_5
Conference Paper (published)
Local optima networks, landscape autocorrelation and heuristic search performance
Chicano F, Daolio F, Ochoa G, Verel S, Tomassini M & Alba E (2012) Local optima networks, landscape autocorrelation and heuristic search performance. In: Coello CC, Cutello V, Deb K K, Forrest S, Nicosia G & Pavone M (eds.) Parallel Problem Solving from Nature - PPSN XII: 12th International Conference, Taormina, Italy, September 1-5, 2012, Proceedings, Part II. Lecture Notes in Computer Science, 7492. PPSN 2012 - 12th International Conference on Parallel Problem Solving from Nature, Taormina, Italy, 01.09.2012-05.09.2012. Berlin Heidelberg: Springer, pp. 337-347. http://link.springer.com/chapter/10.1007/978-3-642-32964-7_34#; https://doi.org/10.1007/978-3-642-32964-7_34
Conference Paper (published)
Hyper-heuristics and cross-domain optimization
Ochoa G (2012) Hyper-heuristics and cross-domain optimization. In: Soule T (ed.) GECCO '12 - Proceedings of the 14th annual conference companion on Genetic and Evolutionary Computation. 14th Annual Genetic and Evolutionary Computation Conference, Philadelphia, 07.07.2012-11.07.2012. New York: ACM, pp. 1197-1214. http://dl.acm.org/citation.cfm?id=2330937; https://doi.org/10.1145/2330784.2330937
Conference Paper (published)
HyFlex: A benchmark framework for cross-domain heuristic search
Ochoa G, Hyde M, Curtois T, Vazquez-Rodriguez JA, Walker J, Gendreau M, Kendall G, McCollum B, Parkes AJ, Petrovic S & Burke E (2012) HyFlex: A benchmark framework for cross-domain heuristic search. In: Hao J & Middendorf M (eds.) Evolutionary Computation in Combinatorial Optimization 12th European Conference, EvoCOP 2012, Málaga, Spain, April 11-13, 2012. Proceedings. Lecture Notes in Computer Science, Vol. 7245. 12th European Conference, EvoCOP 2012, Málaga, Spain, 11.04.2012-12.04.2012. Amsterdam: Springer, pp. 136-147. http://link.springer.com/chapter/10.1007/978-3-642-29124-1_12
Conference Paper (published)
Adaptive evolutionary algorithms and extensions to the HyFlex hyper-heuristic framework
Ochoa G, Walker J, Hyde M & Curtois T (2012) Adaptive evolutionary algorithms and extensions to the HyFlex hyper-heuristic framework. In: Coello CC, Cutello V, Deb K K, Forrest S, Nicosia G & Pavone M (eds.) Parallel Problem Solving from Nature - PPSN XII: 12th International Conference, Taormina, Italy, September 1-5, 2012, Proceedings, Part II. Lecture Notes in Computer Science, Vol. 7492. 12th International Conference, Taormina, Italy, 01.09.2012-05.09.2012. Amsterdam: Springer, pp. 418-427. http://link.springer.com/chapter/10.1007%2F978-3-642-32964-7_42#
Conference Paper (published)
Local optima networks and the performance of iterated local search
Daolio F, Verel S, Ochoa G & Tomassini M (2012) Local optima networks and the performance of iterated local search. In: GECCO'12 - Proceedings of the 14th International Conference on Genetic and Evolutionary Computation. GECCO '12 - Fourteenth international conference on Genetic and evolutionary computation, Philadelphia, PA, USA, 07.07.2012-11.07.2012. New York, NY, USA: ACM, pp. 369-376. http://dl.acm.org/citation.cfm?id=2330217; https://doi.org/10.1145/2330163.2330217
Article
Editorial for the Special Issue on Automated Design and Assessment of Heuristic Search Methods
Ochoa G, Preuss M, Bartz-Beielstein T & Schoenauer M (2012) Editorial for the Special Issue on Automated Design and Assessment of Heuristic Search Methods. Evolutionary Computation, 20 (2), pp. 161-163. https://doi.org/10.1162/EVCO_e_00071
Article
Fitness landscapes and the Andrews-Curtis conjecture
Swan J, Ochoa G, Kendall G & Edjvet M (2012) Fitness landscapes and the Andrews-Curtis conjecture. International Journal of Algebra and Computation, 22 (2), p. 1250009. https://doi.org/10.1142/S0218196711006753
Article
Local Optima Networks of NK Landscapes With Neutrality
Verel S, Ochoa G & Tomassini M (2011) Local Optima Networks of NK Landscapes With Neutrality. IEEE Transactions on Evolutionary Computation, 15 (6), pp. 783-797. https://doi.org/10.1109/TEVC.2010.2046175
Conference Paper (published)
Clustering of local optima in combinatorial fitness landscapes
Ochoa G, Verel S, Daolio F & Tomassini M (2011) Clustering of local optima in combinatorial fitness landscapes. In: Coello CC (ed.) Learning and Intelligent Optimization: 5th International Conference, LION 5, Rome, Italy, January 17-21, 2011. Selected Papers. Lecture Notes in Computer Science, 6683. LION 5, 5th International Conference on Learning and Intelligent Optimization, Rome, Italy, 17.01.2011-21.01.2011. Berlin Heidelberg: Springer, pp. 454-457. http://link.springer.com/chapter/10.1007/978-3-642-25566-3_35#
Conference Paper (published)
The Cross-domain Heuristic Search Challenge -- An International Research Competition
Burke E, Gendreau M, Hyde M, Kendall G, McCollum B, Ochoa G, Parkes AJ & Petrovic S (2011) The Cross-domain Heuristic Search Challenge -- An International Research Competition. In: Coello CC (ed.) Learning and Intelligent Optimization: 5th International Conference, LION 5, Rome, Italy, January 17-21, 2011. Selected Papers. Lecture Notes in Computer Science, 6683. LION 5 - 5th International Conference on Learning and Intelligent Optimization, Rome, Italy, 17.01.2011-21.01.2011. Berlin Heidelberg: Springer, pp. 631-634. http://link.springer.com/chapter/10.1007/978-3-642-25566-3_49#; https://doi.org/10.1007/978-3-642-25566-3_49
Conference Paper (published)
Partial neighborhoods of the Traveling Salesman Problem
Whitley D & Ochoa G (2011) Partial neighborhoods of the Traveling Salesman Problem. In: GECCO'11 - Genetic and Evolutionary Computation Conference Proceedings. GECCO '11 - 13th annual conference on Genetic and evolutionary computation, Dublin, Ireland, 12.07.2011-16.07.2011. New York, NY, USA: ACM, pp. 529-536. http://dl.acm.org/citation.cfm?id=2001649; https://doi.org/10.1145/2001576.2001649
Conference Paper (published)
Adaptive iterated local search for cross-domain optimisation
Burke E, Gendreau M, Ochoa G & Walker J (2011) Adaptive iterated local search for cross-domain optimisation. In: Krasnogor N & Lanzi P (eds.) GECCO'11 Proceedings of the 13th annual conference on Genetic and Evolutionary Computation. 13th annual conference on Genetic and evolutionary computation, Dublin, Ireland, 12.07.2011-16.07.2011. New York, NY: ACM, pp. 1987-1994. http://dl.acm.org/citation.cfm?doid=2001576.2001843; https://doi.org/10.1145/2001576.2001843
Conference Paper (published)
Ochoa G, Hyde M & Burke E (2011) Automated heuristic design. In: GECCO '11 Proceedings of the 13th annual conference companion on Genetic and evolutionary computation. 13th annual conference on Genetic and evolutionary computation, Dublin, Ireland, 12.07.2011-16.07.2011. New York, NY: ACM, pp. 1321-1341. http://dl.acm.org/citation.cfm?doid=2001858.2002139; https://doi.org/10.1145/2001858.2002139
Article
Communities of minima in local optima networks of combinatorial spaces
Daolio F, Tomassini M, Verel S & Ochoa G (2011) Communities of minima in local optima networks of combinatorial spaces. Physica A: Statistical Mechanics and its Applications, 390 (9), pp. 1684-1694. https://doi.org/10.1016/j.physa.2011.01.005
Article
Vazquez-Rodriguez JA & Ochoa G (2011) On the automatic discovery of variants of the NEH procedure for flow shop scheduling using genetic programming. Journal of the Operational Research Society, 62 (2), pp. 381-396. https://doi.org/10.1057/jors.2010.132
Conference Paper (published)
Iterated Local Search vs. Hyper-heuristics: Towards General-Purpose Search Algorithms
Burke E, Curtois T, Hyde M, Kendall G, Ochoa G, Petrovic S, Vazquez-Rodriguez JA & Gendreau M (2010) Iterated Local Search vs. Hyper-heuristics: Towards General-Purpose Search Algorithms. In: 2010 IEEE Congress on Evolutionary Computation. 2010 IEEE Congress on Evolutionary Computation, Barcelona, 18.07.2010-23.07.2010. Piscataway, NJ, USA: IEEE Press. https://doi.org/10.1109/CEC.2010.5586064
Book Chapter
First-Improvement vs. Best-Improvement Local Optima Networks of NK Landscapes
Ochoa G, Verel S & Tomassini M (2010) First-Improvement vs. Best-Improvement Local Optima Networks of NK Landscapes. In: Schaefer R, Cotta C, Kolodziej J & Rudolph G (eds.) Parallel Problem Solving from Nature, PPSN XI: 11th International Conference, Kraków, Poland, September 11-15, 2010, Proceedings, Part I. Lecture Notes in Computer Science, 6238. Berlin Heidelberg: Springer, pp. 104-113. http://link.springer.com/chapter/10.1007%2F978-3-642-15844-5_11?LI=true#; https://doi.org/10.1007/978-3-642-15844-5_11
Article
Special issue on hyper-heuristics in search and optimization
Ochoa G & Ozcan E (2010) Special issue on hyper-heuristics in search and optimization. Journal of Heuristics, 16 (6), pp. 745-748. https://doi.org/10.1007/s10732-010-9147-x
Book Chapter
A Classification of Hyper-heuristic Approaches
Burke E, Hyde M, Kendall G, Ochoa G, Ozcan E & Woodward J (2010) A Classification of Hyper-heuristic Approaches. In: Gendreau M & Potvin J (eds.) Handbook of Metaheuristics. International Series in Operations Research & Management Science, 146. Berlin: Springer, pp. 449-468. http://www.springerlink.com/content/xxm7126130381913/
Conference Paper (published)
Local optima networks of the quadratic assignment problem
Daolio F, Verel S, Ochoa G & Tomassini M (2010) Local optima networks of the quadratic assignment problem. In: 2010 IEEE World Congress on Computational Intelligence, WCCI 2010 - 2010 IEEE Congress on Evolutionary Computation, CEC 2010. 2010 IEEE Congress on Evolutionary Computation (CEC), Barcelona, Spain, 18.07.2010-23.07.2010. Piscataway, NJ: IEEE. http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?arnumber=5586481&abstractAccess=no&userType=inst; https://doi.org/10.1109/CEC.2010.5586481
Article
A Reinforcement Learning - Great-Deluge Hyper-Heuristic for Examination Timetabling
Ozcan E, Misir M, Ochoa G & Burke E (2010) A Reinforcement Learning - Great-Deluge Hyper-Heuristic for Examination Timetabling. International Journal of Applied Metaheuristic Computing, 1 (1), pp. 39-59. https://doi.org/10.4018/jamc.2010102603
Article
Modeling and optimization of combined cytostatic and cytotoxic cancer chemotherapy
Villasana M, Ochoa G & Aguilar S (2010) Modeling and optimization of combined cytostatic and cytotoxic cancer chemotherapy. Artificial Intelligence in Medicine, 50 (3), pp. 163-173. https://doi.org/10.1016/j.artmed.2010.05.009
Conference Paper (published)
The connectivity of NK landscapes' basins: A network analysis
Verel S, Ochoa G & Tomassini M (2010) The connectivity of NK landscapes' basins: A network analysis. In: Bullock S, Noble J, Watson R & Bedau M (eds.) Artificial Life XI: Proceedings of the Eleventh International Conference on the Simulation and Synthesis of Living Systems. Artificial Life XI: Eleventh International Conference on the Simulation and Synthesis of Living Systems, Winchester, UK, 05.08.2008-08.08.2008. Cambridge, MA: MIT Press, pp. 648-655. http://mitpress.mit.edu/books/artificial-life-xi
Conference Paper (published)
Towards the Decathlon Challenge of Search Heuristics
Burke E, Curtois T, Kendall G, Hyde M, Ochoa G & Vazquez-Rodriguez JA (2009) Towards the Decathlon Challenge of Search Heuristics. In: GECCO '09 Proceedings of the 11th Annual Conference Companion on Genetic and Evolutionary Computation Conference: Late Breaking Papers. GECCO '09 - 11th Annual Conference Companion on Genetic and Evolutionary Computation, Montreal, Canada, 08.07.2009-12.07.2009. New York, NY, USA: ACM, pp. 2005-2208. http://dl.acm.org/citation.cfm?id=1570303; https://doi.org/10.1145/1570256.1570303
Conference Paper (published)
A PSO/ACO Approach to Knowledge Discovery in a Pharmacovigilance Context
Sordo M, Ochoa G & Murphy SN (2009) A PSO/ACO Approach to Knowledge Discovery in a Pharmacovigilance Context. In: GECCO '09 Proceedings of the 11th Annual Conference Companion on Genetic and Evolutionary Computation Conference: Late Breaking Papers. GECCO '09: 11th Annual Conference on Genetic and Evolutionary Computation, Montreal, Canada, 08.07.2009-12.07.2009. New York, NY, USA: ACM, pp. 2679-2684. http://dl.acm.org/citation.cfm?id=1570382; https://doi.org/10.1145/1570256.1570382
Conference Paper (published)
HyFlex: A Flexible Framework for the Design and Analysis of Hyper-heuristics
Burke E, Curtois T, Hyde M, Kendall G, Ochoa G, Petrovic S & Vazquez-Rodriguez JA (2009) HyFlex: A Flexible Framework for the Design and Analysis of Hyper-heuristics. In: Proceedings of the 4th Multidisciplinary International Scheduling Conference: Theory and Applications (MISTA 2009). Multidisciplinary International Conference on Scheduling: Theorey and Applications (MISTA 2009), Dublin, Ireland, 10.08.2009-12.08.2009. Switzerland: Springer, pp. 790-797. http://www.mistaconference.org/2009/abstracts/790-797-112-A.pdf
Conference Paper (published)
Cheating for problem solving: A genetic algorithm with social interactions
Lahoz-Beltra R, Ochoa G & Aickelin U (2009) Cheating for problem solving: A genetic algorithm with social interactions. In: Proceedings of the 11th Annual Genetic and Evolutionary Computation Conference, GECCO-2009. GECCO '09 - 11th Annual conference on Genetic and evolutionary computation, Montreal, Canada, 08.07.2009-12.07.2009. New York, NY, USA: ACM, pp. 811-817. http://dl.acm.org/citation.cfm?id=1570013; https://doi.org/10.1145/1569901.1570013
Conference Paper (published)
Analyzing the landscape of a graph based hyper-heuristic for timetabling problems
Ochoa G, Qu R & Burke E (2009) Analyzing the landscape of a graph based hyper-heuristic for timetabling problems. In: Proceeding GECCO '09 Proceedings of the 11th Annual conference on Genetic and evolutionary computation. 11th Annual Genetic and Evolutionary Computation Conference (GECCO-2009), Montréal, Canada, 08.07.2009-12.07.2009. New York, NY: ACM, pp. 341-348. http://dl.acm.org/citation.cfm?id=1569949&CFID=230982929&CFTOKEN=65117036; https://doi.org/10.1145/1569901.1569949
Book Chapter
Exploring hyper-heuristic methodologies with genetic programming
Burke E, Hyde M, Kendall G, Ochoa G, Ozcan E & Woodward J (2009) Exploring hyper-heuristic methodologies with genetic programming. In: Mumford C & Jain L (eds.) Computational Intelligence: Collaboration, Fusion and Emergence. Intelligent Systems Reference Library, 1, Volume 1. Berlin and Heidelberg: Springer, pp. 177-201. http://www.springerlink.com/content/j11565558t12900u/
Conference Paper (published)
Dispatching Rules for Production Scheduling: a Hyper-heuristic Landscape Analysis
Ochoa G, Vazquez-Rodriguez JA, Petrovic S & Burke E (2009) Dispatching Rules for Production Scheduling: a Hyper-heuristic Landscape Analysis. In: IEEE Congress on Evolutionary Computation, 2009 CEC '09. Piscataway, NJ, USA: IEEE Press, pp. 1873-1880. http://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=4983169&isnumber=4982922; https://doi.org/10.1109/CEC.2009.4983169
Technical Report
A Classification of Hyper-heuristic Approaches
Burke E, Hyde M, Kendall G, Ochoa G, Ozcan E & Woodward J (2009) A Classification of Hyper-heuristic Approaches. Computer Science Technical Report, NOTTCS-TR-SUB-0906241359-0664. University of Nottingham. http://www.cs.stir.ac.uk/~jrw/publications/AClassificationHyperHeuristicApproaches.pdf
Conference Paper (published)
A study of NK landscapes' basins and local optima networks
Ochoa G, Tomassini M, Verel S & Darabos C (2008) A study of NK landscapes' basins and local optima networks. In: GECCO'08: Proceedings of the 10th Annual Conference on Genetic and Evolutionary Computation 2008. GECCO '08 - 10th annual conference on Genetic and evolutionary computation, Atlanta, GA, USA, 12.07.2008-16.07.2008. New York, NY, USA: ACM, pp. 555-562. http://dl.acm.org/citation.cfm?id=1389204; https://doi.org/10.1145/1389095.1389204
Article
Complex-network analysis of combinatorial spaces: The NK landscape case
Tomassini M, Verel S & Ochoa G (2008) Complex-network analysis of combinatorial spaces: The NK landscape case. Physical Review E, 78 (6). https://doi.org/10.1103/PhysRevE.78.066114
Book Chapter
The cooperative royal road: Avoiding Hitchhiking
Ochoa G, Lutton E & Burke E (2008) The cooperative royal road: Avoiding Hitchhiking. In: Monmarche N, Talbi E, Collet P, Schoenauer M & Lutton E (eds.) Artificial Evolution: 8th International Conference, Evolution Artificielle, EA 2007, Tours, France, October 29-31, 2007, Revised Selected Papers. Lecture Notes in Computer Science, 4926. Berlin Heidelberg: Springer, pp. 184-195. http://link.springer.com/chapter/10.1007%2F978-3-540-79305-2_16?LI=true#; https://doi.org/10.1007/978-3-540-79305-2_16
Presentation / Talk
Categorisation of Approaches and Formal Framework for Hyper-Heuristics
Woodward J, Parkes AJ & Ochoa G (2008) Categorisation of Approaches and Formal Framework for Hyper-Heuristics. 10th International Conference on Parallel Problem Solving From Nature (PPSN-08), Dortmund, Germany, 13.09.2008-17.09.2008. http://ls11-www.cs.uni-dortmund.de/ppsn/ppsn10/data/ppsn2008_program.pdf
Article
An evolutionary approach to cancer chemotherapy scheduling
Ochoa G, Villasana M & Burke E (2007) An evolutionary approach to cancer chemotherapy scheduling. Genetic Programming and Evolvable Machines, 8 (4), pp. 301-318. https://doi.org/10.1007/s10710-007-9041-y
Book Chapter
A critical view of the evolutionary design of self-assembling systems
Krasnogor N, Terrazas G, Pelta DA & Ochoa G (2006) A critical view of the evolutionary design of self-assembling systems. In: Talbi E, Liardet P, Collet P, Lutton E & Schoenauer M (eds.) Artificial Evolution: 7th International Conference, Evolution Artificielle, EA 2005, Revised Selected Papers. Lecture Notes in Computer Science, 3871. Berlin Heidelberg: Springer, pp. 179-188. http://www.springer.com/computer/theoretical+computer+science/book/978-3-540-33589-4; https://doi.org/10.1007/11740698_16
Book Chapter
Incorporating knowledge of secondary structures in a L-system-based encoding for protein folding
Ochoa G, Escuela G & Krasnogor N (2006) Incorporating knowledge of secondary structures in a L-system-based encoding for protein folding. In: Talbi E, Liardet P, Collet P, Lutton E & Schoenauer M (eds.) Artificial Evolution: 7th International Conference, Evolution Artificielle, EA 2005, Lille, France, October 26-28, 2005, Revised Selected Papers. Lecture Notes in Computer Science, 3871. Berlin Heidelberg: Springer, pp. 247-258. http://link.springer.com/chapter/10.1007%2F11740698_22?LI=true#; https://doi.org/10.1007/11740698_22
Conference Paper (published)
Assortative mating drastically alters the magnitude of error thresholds
Ochoa G & Jaffe K (2006) Assortative mating drastically alters the magnitude of error thresholds. In: Runarsson T, Beyer H, Burke E, Merelo-Guervos J, Whitley L & Yao X (eds.) Parallel Problem Solving from Nature - PPSN IX: 9th International Conference, Reykjavik, Iceland, September 9-13, 2006, Proceedings. Lecture Notes in Computer Science, 4193. 9th International Conference on Parallel Problem Solving from Nature - PPSN IX - 2006, Reykjavik, Iceland, 09.09.2006-12.09.2006. Berlin Heidelberg: Springer, pp. 890-899. http://link.springer.com/chapter/10.1007/11844297_90#
Article
Error thresholds in genetic algorithms
Ochoa G (2006) Error thresholds in genetic algorithms. Evolutionary Computation, 14 (2), pp. 157-182. https://doi.org/10.1162/evco.2006.14.2.157
Conference Paper (published)
Assortative mating in genetic algorithms for dynamic problems
Ochoa G, Madler-Kron C, Rodriguez R & Jaffe K (2005) Assortative mating in genetic algorithms for dynamic problems. In: Rothlauf F, Branke J, Cagnoni S, Wolfe CD, Dreschsler R, Jin Y, Machado P, Marchiori E, Romero J, Smith G & Squillero G (eds.) Applications of Evolutionary Computing: EvoWorkkshops 2005: EvoBIO, EvoCOMNET, EvoHOT, EvoIASP, EvoMUSART, and EvoSTOC Lausanne, Switzerland, March 30 - April 1, 2005 Proceedings. Lecture Notes in Computer Science, 3449. EvoWorkshops 2005: EvoBIO, EvoCOMNET, EvoHOT, EvoIASP, EvoMUSART, and EvoSTOC, Lausanne, Switzerland, 30.03.2005-01.04.2005. Berlin Heidelberg: Springer, pp. 617-622. http://link.springer.com/chapter/10.1007/978-3-540-32003-6_65#
Book Chapter
Evolving L-systems to capture protein structure native conformations
Escuela G, Ochoa G & Krasnogor N (2005) Evolving L-systems to capture protein structure native conformations. In: Keijzer M, Tettamanzi A, Collet P, van Hemert J & Tomassini M (eds.) Genetic Programming: 8th European Conference, EuroGP 2005, Lausanne, Switzerland, March 30-April 1, 2005, Proceedings. Lecture Notes in Computer Science, 3447. Berlin Heidelberg: Springer, pp. 74-84. http://link.springer.com/chapter/10.1007%2F978-3-540-31989-4_7?LI=true#; https://doi.org/10.1007/978-3-540-31989-4_7
Article
Heuristic design of cancer chemotherapies
Villasana M & Ochoa G (2004) Heuristic design of cancer chemotherapies. IEEE Transactions on Evolutionary Computation, 8 (6), pp. 513-521. https://doi.org/10.1109/TEVC.2004.834154
Conference Paper (published)
Setting the Mutation Rate: Scope and Limitations of the 1/L Heuristic
Ochoa G (2002) Setting the Mutation Rate: Scope and Limitations of the 1/L Heuristic. In: GECCO '02 Proceedings of the Genetic and Evolutionary Computation Conference. Genetic and Evolutionary Computation Conference (GECCO-2002), New York, NY, USA, 09.07.2002-13.07.2002. San Francisco, CA, USA: Morgan Kaufman, pp. 495-502. http://dl.acm.org/citation.cfm?id=683104
Conference Paper (published)
Ochoa G (2000) Consensus Sequence Plots and Error Thresholds: Tools for Visualising the Structure of Fitness Landscapes. In: Schoenauer M, Deb K K, Rudolph G, Yao X, Lutton E, Merelo J & Schwefel H (eds.) Parallel Problem Solving from Nature PPSN VI: 6th International Conference Paris, France, September 18–20, 2000 Proceedings. Lecture Notes in Computer Science, 1917. 6th International Conference on Parallel Problem Solving from Nature PPSN VI - 2000, Paris, France, 18.09.2000-20.09.2000. Berlin Heidelberg: Springer, pp. 129-138. http://link.springer.com/chapter/10.1007/3-540-45356-3_13#; https://doi.org/10.1007/3-540-45356-3_13
Conference Paper (published)
Optimal Mutation Rates and Selection Pressure in Genetic Algorithms
Ochoa G, Harvey I & Buxton H (2000) Optimal Mutation Rates and Selection Pressure in Genetic Algorithms. In: Genetic and Evolutionary Computation Conference (GECCO-2000). Genetic and Evolutionary Computation Conference (GECCO-2000), Las Vegas, NV, USA, 08.07.2000-12.07.2000. San Francisco, CA, USA: Morgan Kaufman, pp. 315-322.
Thesis
Error Thresholds and Optimal Mutation Rates in Genetic Algorithms
Ochoa G (2000) Error Thresholds and Optimal Mutation Rates in Genetic Algorithms. Doctor of Philosophy. University of Sussex.
Conference Paper (published)
On recombination and optimal mutation rates
Ochoa G, Harvey I & Buxton H (1999) On recombination and optimal mutation rates. In: Banzhaf W, Daida J, Eiben A, Garzon M, Honavar V, Jakiela M & Smith R (eds.) GECCO-99: Proceedings of the Genetic and Evolutionary Computation Conference, Volume 1. Genetic and Evolutionary Computation Conference (GECCO-99), Orlando, FL, USA, 13.07.1999-17.07.1999. San Francisco, CA, USA: Morgan Kaufman, pp. 488-495. http://www.cs.colostate.edu/~genitor/GECCO-1999/submitting.html
Conference Paper (published)
Error thresholds and their relation to optimal mutation rates
Ochoa G, Harvey I & Buxton H (1999) Error thresholds and their relation to optimal mutation rates. In: Floreano D, Nicoud J & Mondada F (eds.) Advances in Artificial Life: 5th European Conference, ECAL’99 Lausanne, Switzerland, September 13–17, 1999 Proceedings. Lecture Notes in Computer Science, 1674. 5th European Conference on Advances in Artificial Life, ECAL’99, Lausanne, Switzerland, 13.09.1999-17.09.1999. Berlin Heidelberg: Springer, pp. 54-63. http://link.springer.com/chapter/10.1007/3-540-48304-7_10#; https://doi.org/10.1007/3-540-48304-7_10
Conference Paper (published)
Recombination and error thresholds in finite populations
Ochoa G & Harvey I (1999) Recombination and error thresholds in finite populations. In: Banzhaf W & Reeves C (eds.) Foundations of Genetic Algorithms, Volume 5. Foundations of Genetic Algorithms, 5. 1998 Foundations of Genetic Algorithms (FOGA-5), Amsterdam, The Netherlands, 24.09.1998-28.09.1998. San Francisco, CA, USA: Morgan Kaufman, pp. 245-264.
Article
On Sex, Mate Selection and the Red Queen
Ochoa G & Jaffe K (1999) On Sex, Mate Selection and the Red Queen. Journal of Theoretical Biology, 199 (1), pp. 1-9. https://doi.org/10.1006/jtbi.1999.0931
Conference Paper (published)
On genetic algorithms and lindenmayer systems
Ochoa G (1998) On genetic algorithms and lindenmayer systems. In: Eiben A, Back T, Schoenauer M & Schwefel H (eds.) Parallel Problem Solving from Nature — PPSN V: 5th International Conference Amsterdam, The Netherlands September 27–30, 1998 Proceedings. Lecture Notes in Computer Science, 1498. 5th International Conference on Parallel Problem Solving from Nature — PPSN 1998, Amsterdam, The Netherlands, 27.09.1998-30.09.1998. Berlin Heidelberg: Springer, pp. 335-344. http://link.springer.com/chapter/10.1007/BFb0056876#
Thesis
Un Modelo de Vida Artificial para Evolucionar Formas Vegetales
Ochoa G (1996) Un Modelo de Vida Artificial para Evolucionar Formas Vegetales [An Artificial Life Model for Evolving Plant-like Structures]. Master of Science. Universidad Simon Bolivar, Caracas, Venezuela.
Presentation / Talk
Simulación de la Evolución de Formas Vegetales
Ochoa G & Moreno JA (1995) Simulación de la Evolución de Formas Vegetales. Conferencia Nacional en Inteligencia Artificial (CENIASE’95), Puerto Ordaz, Venezuela.