{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T12:08:57Z","timestamp":1780315737148,"version":"3.54.1"},"reference-count":45,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2018,7,16]],"date-time":"2018-07-16T00:00:00Z","timestamp":1531699200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"<jats:p>Among neural disorders related to movement, essential tremor has the highest prevalence; in fact, it is twenty times more common than Parkinson\u2019s disease. The drawing of the Archimedes\u2019 spiral is the gold standard test to distinguish between both pathologies. The aim of this paper is to select non-linear biomarkers based on the analysis of digital drawings. It belongs to a larger cross study for early diagnosis of essential tremor that also includes genetic information. The proposed automatic analysis system consists in a hybrid solution: Machine Learning paradigms and automatic selection of features based on statistical tests using medical criteria. Moreover, the selected biomarkers comprise not only commonly used linear features (static and dynamic), but also other non-linear ones: Shannon entropy and Fractal Dimension. The results are hopeful, and the developed tool can easily be adapted to users; and taking into account social and economic points of view, it could be very helpful in real complex environments.<\/jats:p>","DOI":"10.3390\/e20070531","type":"journal-article","created":{"date-parts":[[2018,7,16]],"date-time":"2018-07-16T04:05:33Z","timestamp":1531713933000},"page":"531","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":28,"title":["Automatic Analysis of Archimedes\u2019 Spiral for Characterization of Genetic Essential Tremor Based on Shannon\u2019s Entropy and Fractal Dimension"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2135-2393","authenticated-orcid":false,"given":"Karmele","family":"Lopez-de-Ipina","sequence":"first","affiliation":[{"name":"Systems Engineering and Automation Department, EleKin Research Group, University of the Basque Country UPV\/EHU, 20018 Donostia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6534-1979","authenticated-orcid":false,"given":"Jordi","family":"Sol\u00e9-Casals","sequence":"additional","affiliation":[{"name":"Data and Signal Processing Research Group, University of Vic\u2014Central University of Catalonia, 08500 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0605-1282","authenticated-orcid":false,"given":"Marcos","family":"Fa\u00fandez-Zanuy","sequence":"additional","affiliation":[{"name":"Escola Superior Polit\u00e8cnica Tecnocampus, Universitat Pompeu Fabra, 08002 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Pilar M.","family":"Calvo","sequence":"additional","affiliation":[{"name":"Systems Engineering and Automation Department, EleKin Research Group, University of the Basque Country UPV\/EHU, 20018 Donostia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Enric","family":"Sesa","sequence":"additional","affiliation":[{"name":"Escola Superior Polit\u00e8cnica Tecnocampus, Universitat Pompeu Fabra, 08002 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Josep","family":"Roure","sequence":"additional","affiliation":[{"name":"Escola Superior Polit\u00e8cnica Tecnocampus, Universitat Pompeu Fabra, 08002 Barcelona, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Unai","family":"Martinez-de-Lizarduy","sequence":"additional","affiliation":[{"name":"Department of Electronic Technology, EleKin Research Group, University of the Basque Country UPV\/EHU, 20018 Donostia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Blanca","family":"Beitia","sequence":"additional","affiliation":[{"name":"Department of Mathematics, EleKin Research Group, University of the Basque Country UPV\/EHU, 1006 Gasteiz, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9142-7752","authenticated-orcid":false,"given":"Elsa","family":"Fern\u00e1ndez","sequence":"additional","affiliation":[{"name":"Systems Engineering and Automation Department, EleKin Research Group, University of the Basque Country UPV\/EHU, 20018 Donostia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jon","family":"Iradi","sequence":"additional","affiliation":[{"name":"Department of Enterprises Organization, EleKin Research Group, University of the Basque Country UPV\/EHU, 20018 Donostia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joseba","family":"Garcia-Melero","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, EleKin Research Group, University of the Basque Country UPV\/EHU, 1006 Gasteiz, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alberto","family":"Bergareche","sequence":"additional","affiliation":[{"name":"Department of Neuroscience, BioDonostia Health Institute, 20014 Donostia, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,7,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"534","DOI":"10.1002\/mds.22838","article-title":"How common is the most common adult movement disorder? 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