{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,26]],"date-time":"2026-08-26T01:28:16Z","timestamp":1787707696733,"version":"build-2784847793"},"reference-count":14,"publisher":"MIT Press - Journals","issue":"1","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Computational Linguistics"],"published-print":{"date-parts":[[2013,3]]},"abstract":"<jats:p> Dependency trees used in syntactic parsing often include a root node representing a dummy word prefixed or suffixed to the sentence, a device that is generally considered a mere technical convenience and is tacitly assumed to have no impact on empirical results. We demonstrate that this assumption is false and that the accuracy of data-driven dependency parsers can in fact be sensitive to the existence and placement of the dummy root node. In particular, we show that a greedy, left-to-right, arc-eager transition-based parser consistently performs worse when the dummy root node is placed at the beginning of the sentence (following the current convention in data-driven dependency parsing) than when it is placed at the end or omitted completely. Control experiments with an arc-standard transition-based parser and an arc-factored graphbased parser reveal no consistent preferences but nevertheless exhibit considerable variation in results depending on root placement. We conclude that the treatment of dummy root nodes in data-driven dependency parsing is an underestimated source of variation in experiments andmay also be a parameter worth tuning for some parsers. <\/jats:p>","DOI":"10.1162\/coli_a_00132","type":"journal-article","created":{"date-parts":[[2012,11,13]],"date-time":"2012-11-13T14:42:31Z","timestamp":1352817751000},"page":"5-13","source":"Crossref","is-referenced-by-count":15,"title":["Going to the Roots of Dependency Parsing"],"prefix":"10.1162","volume":"39","author":[{"given":"Miguel","family":"Ballesteros","sequence":"first","affiliation":[{"name":"Complutense University of Madrid"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joakim","family":"Nivre","sequence":"additional","affiliation":[{"name":"Uppsala University"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"281","reference":[{"key":"R1","doi-asserted-by":"publisher","DOI":"10.3115\/1620853.1620925"},{"key":"R2","doi-asserted-by":"publisher","DOI":"10.1007\/978-94-010-0201-1_7"},{"key":"R3","doi-asserted-by":"publisher","DOI":"10.3115\/1596276.1596305"},{"key":"R4","first-page":"449","volume-title":"Proceedings of the 5th International Conference on Language Resources and Evaluation (LREC)","author":"de Marneffe Marie-Catherine","year":"2006"},{"key":"R6","first-page":"933","volume-title":"Proceedings of the CoNLL Shared Task of EMNLP-CoNLL 2007","author":"Hall Johan","year":"2007"},{"key":"R7","first-page":"313","volume":"19","author":"Marcus Mitchell P.","year":"1993","journal-title":"Computational Linguistics"},{"key":"R8","unstructured":"McDonald, Ryan. 2006.Discriminative Learning and Spanning Tree Algorithms for Dependency Parsing.Ph.D. thesis, University of Pennsylvania."},{"key":"R9","doi-asserted-by":"publisher","DOI":"10.3115\/1220575.1220641"},{"key":"R10","first-page":"149","volume-title":"Proceedings of the 8th International Workshop on Parsing Technologies (IWPT)","author":"Nivre Joakim","year":"2003"},{"key":"R11","doi-asserted-by":"publisher","DOI":"10.3115\/1613148.1613156"},{"key":"R12","doi-asserted-by":"publisher","DOI":"10.1007\/1-4020-4889-0"},{"key":"R13","first-page":"915","volume-title":"Proceedings of the CoNLL Shared Task of EMNLP-CoNLL 2007","author":"Nivre Joakim","year":"2007"},{"key":"R14","first-page":"2216","volume-title":"Proceedings of the 5th International Conference on Language Resources and Evaluation (LREC)","author":"Nivre Joakim","year":"2006"},{"key":"R15","doi-asserted-by":"publisher","DOI":"10.3115\/1219840.1219853"}],"container-title":["Computational Linguistics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mitpressjournals.org\/doi\/pdf\/10.1162\/COLI_a_00132","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2021,3,12]],"date-time":"2021-03-12T21:27:20Z","timestamp":1615584440000},"score":1,"resource":{"primary":{"URL":"https:\/\/direct.mit.edu\/coli\/article\/39\/1\/5-13\/1419"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2013,3]]},"references-count":14,"journal-issue":{"issue":"1","published-print":{"date-parts":[[2013,3]]}},"alternative-id":["10.1162\/COLI_a_00132"],"URL":"https:\/\/doi.org\/10.1162\/coli_a_00132","relation":{},"ISSN":["0891-2017","1530-9312"],"issn-type":[{"value":"0891-2017","type":"print"},{"value":"1530-9312","type":"electronic"}],"subject":[],"published":{"date-parts":[[2013,3]]}}}