{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,16]],"date-time":"2025-12-16T12:30:50Z","timestamp":1765888250651,"version":"build-2065373602"},"reference-count":33,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2019,12,9]],"date-time":"2019-12-09T00:00:00Z","timestamp":1575849600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005416","name":"Norges forskningsr\u00e5d","doi-asserted-by":"publisher","award":["244599"],"award-info":[{"award-number":["244599"]}],"id":[{"id":"10.13039\/501100005416","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Climate-KIC 2017: Pathfinder 2","award":["TreeTime"],"award-info":[{"award-number":["TreeTime"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>Tree species classification at individual tree crowns (ITCs) level, using remote-sensing data, requires the availability of a sufficient number of reliable reference samples (i.e., training samples) to be used in the learning phase of the classifier. The classification performance of the tree species is mainly affected by two main issues: (i) an imbalanced distribution of the tree species classes, and (ii) the presence of unreliable samples due to field collection errors, coordinate misalignments, and ITCs delineation errors. To address these problems, in this paper, we present a weighted Support Vector Machine (wSVM)-based approach for the detection of tree species at ITC level. The proposed approach initially extracts (i) different weights associated to different classes of tree species, to mitigate the effect of the imbalanced distribution of the classes; and (ii) different weights associated to different training samples according to their importance for the classification problem, to reduce the effect of unreliable samples. Then, in order to exploit different weights in the learning phase of the classifier a wSVM algorithm is used. The features to characterize the tree species at ITC level are extracted from both the elevation and intensity of airborne light detection and ranging (LiDAR) data. Experimental results obtained on two study areas located in the Italian Alps show the effectiveness of the proposed approach.<\/jats:p>","DOI":"10.3390\/rs11242948","type":"journal-article","created":{"date-parts":[[2019,12,9]],"date-time":"2019-12-09T11:22:51Z","timestamp":1575890571000},"page":"2948","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["A Weighted SVM-Based Approach to Tree Species Classification at Individual Tree Crown Level Using LiDAR Data"],"prefix":"10.3390","volume":"11","author":[{"given":"Hoang Minh","family":"Nguyen","sequence":"first","affiliation":[{"name":"Department of Sustainable Agro-ecosystems and Bioresources, Research and Innovation Centre, Fondazione E. Mach, Via E. Mach 1, 38010 San Michele all\u2019Adige (TN), Italy"},{"name":"External Affairs Office, Hanoi University of Science and Technology, No.1 Dai Co Viet Street, Hanoi 100000, Vietnam"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2175-7072","authenticated-orcid":false,"given":"Beg\u00fcm","family":"Demir","sequence":"additional","affiliation":[{"name":"Faculty of Electrical Engineering and Computer Science, Technische Universit\u00e4t Berlin, Einsteinufer 17, 10587 Berlin, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9850-8985","authenticated-orcid":false,"given":"Michele","family":"Dalponte","sequence":"additional","affiliation":[{"name":"Department of Sustainable Agro-ecosystems and Bioresources, Research and Innovation Centre, Fondazione E. Mach, Via E. Mach 1, 38010 San Michele all\u2019Adige (TN), Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,12,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"911","DOI":"10.1007\/s10342-011-0481-9","article-title":"Aboveground tree volume and phytomass prediction equations for forest species in Italy","volume":"130","author":"Tabacchi","year":"2011","journal-title":"Eur. J. For. Res."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"258","DOI":"10.1016\/j.rse.2012.03.013","article-title":"Tree species classification in the Southern Alps based on the fusion of very high geometrical resolution multispectral\/hyperspectral images and LiDAR data","volume":"123","author":"Dalponte","year":"2012","journal-title":"Remote Sens. 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