{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,13]],"date-time":"2026-02-13T16:08:57Z","timestamp":1770998937620,"version":"3.50.1"},"reference-count":48,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2020,6,2]],"date-time":"2020-06-02T00:00:00Z","timestamp":1591056000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The electrocardiogram records the heart\u2019s electrical activity and generates a significant amount of data. The analysis of these data helps us to detect diseases and disorders via heart bio-signal abnormality classification. In unbalanced-data contexts, where the classes are not equally represented, the optimization and configuration of the classification models are highly complex, reflecting on the use of computational resources. Moreover, the performance of electrocardiogram classification depends on the approach and parameter estimation to generate the model with high accuracy, sensitivity, and precision. Previous works have proposed hybrid approaches and only a few implemented parameter optimization. Instead, they generally applied an empirical tuning of parameters at a data level or an algorithm level. Hence, a scheme, including metrics of sensitivity in a higher precision and accuracy scale, deserves special attention. In this article, a metaheuristic optimization approach for parameter estimations in arrhythmia classification from unbalanced data is presented. We selected an unbalanced subset of those databases to classify eight types of arrhythmia. It is important to highlight that we combined undersampling based on the clustering method (data level) and feature selection method (algorithmic level) to tackle the unbalanced class problem. To explore parameter estimation and improve the classification for our model, we compared two metaheuristic approaches based on differential evolution and particle swarm optimization. The final results showed an accuracy of 99.95%, a F1 score of 99.88%, a sensitivity of 99.87%, a precision of 99.89%, and a specificity of 99.99%, which are high, even in the presence of unbalanced data.<\/jats:p>","DOI":"10.3390\/s20113139","type":"journal-article","created":{"date-parts":[[2020,6,2]],"date-time":"2020-06-02T09:19:27Z","timestamp":1591089567000},"page":"3139","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["A Metaheuristic Optimization Approach for Parameter Estimation in Arrhythmia Classification from Unbalanced Data"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0943-9936","authenticated-orcid":false,"given":"Juan Carlos","family":"Carrillo-Alarc\u00f3n","sequence":"first","affiliation":[{"name":"Department of Computer Science, Instituto Nacional de Astrof\u00edsica, \u00d3ptica y Electr\u00f3nica (INAOE),  Tonantzintla, Puebla 72840, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4753-9375","authenticated-orcid":false,"given":"Luis Alberto","family":"Morales-Rosales","sequence":"additional","affiliation":[{"name":"Faculty of Civil Engineering, Conacyt-Universidad Michoacana de San Nicol\u00e1s de Hidalgo, Morelia 58030, Michoac\u00e1n, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4999-3472","authenticated-orcid":false,"given":"H\u00e9ctor","family":"Rodr\u00edguez-R\u00e1ngel","sequence":"additional","affiliation":[{"name":"Technological Institute of Culiacan, Culiacan, Sinaloa 80220, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2607-2032","authenticated-orcid":false,"given":"Mariana","family":"Lobato-B\u00e1ez","sequence":"additional","affiliation":[{"name":"Higher Technological Institute of Libres, Libres, Puebla 73780, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8724-8302","authenticated-orcid":false,"given":"Antonio","family":"Mu\u00f1oz","sequence":"additional","affiliation":[{"name":"Engineering Department, University of Guadalajara, Av. Independencia Nacional 151, Autl\u00e1n, Jalisco 48900, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4748-3500","authenticated-orcid":false,"given":"Ignacio","family":"Algredo-Badillo","sequence":"additional","affiliation":[{"name":"Department of Computer Science, Conacyt-Instituto Nacional de Astrof\u00edsica, \u00d3ptica y Electr\u00f3nica (INAOE),  Tonantzintla, Puebla 72840, Mexico"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,2]]},"reference":[{"key":"ref_1","unstructured":"WHO (2019, December 13). Cardiovascular Diseases. Available online: https:\/\/www.who.int\/health-topics\/cardiovascular-diseases\/."},{"key":"ref_2","first-page":"23","article-title":"Computer-aided Arrhythmia Diagnosis with Bio-signal Processing: A Survey of Trends and Techniques","volume":"52","author":"Dinakarrao","year":"2019","journal-title":"Acm Comput. Surv. (Csur)"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Stroobandt, R.X., Barold, S.S., and Sinnaeve, A.F. 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