BEGIN:VCALENDAR VERSION:2.0 PRODID:-//Drupal iCal API//EN X-WR-CALNAME:Events items teaser X-WR-TIMEZONE:America/Toronto BEGIN:VTIMEZONE TZID:America/Toronto X-LIC-LOCATION:America/Toronto BEGIN:DAYLIGHT TZNAME:EDT TZOFFSETFROM:-0500 TZOFFSETTO:-0400 DTSTART:20130310T070000 END:DAYLIGHT BEGIN:STANDARD TZNAME:EST TZOFFSETFROM:-0400 TZOFFSETTO:-0500 DTSTART:20131103T060000 END:STANDARD END:VTIMEZONE BEGIN:VEVENT UID:682210bbad6a5 DTSTART;TZID=America/Toronto:20140226T110000 SEQUENCE:0 TRANSP:TRANSPARENT DTEND;TZID=America/Toronto:20140226T110000 URL:/centre-pattern-analysis-machine-intelligence/event s/invited-talk-modeling-term-associations-probabilistic SUMMARY:Invited Talk: Modeling Term Associations for Probabilistic Informat ion\nRetrieval CLASS:PUBLIC DESCRIPTION:Summary \n\nMODELING TERM ASSOCIATIONS FOR PROBABILISTIC INFORM ATION RETRIEVAL\n\nABSTRACT:\n\nTraditionally\, in many probabilistic retr ieval models\, query terms are\nassumed to be independent. Although such m odels can achieve reasonably\ngood performance\, associations can exist am ong terms from human\nbeing.s point of view. There are some recent studies that investigate\nhow to model term associations/dependencies by proximit y measures.\nHowever\, the modeling of term associations theoretically und er the\nprobabilistic retrieval framework is still largely unexplored. In this\ntalk\, I will introduce a new concept named Cross Term\, to model te rm\nproximity\, with the aim of boosting retrieval performance. With Cross \nTerms\, the association of multiple query terms can be modeled in the\ns ame way as a simple unigram term. In particular\, an occurrence of a\nquer y term is assumed to have an impact on its neighboring text. The\ndegree o f the query term impact gradually weakens with increasing\ndistance from t he place of occurrence. We use shape functions to\ncharacterize such impac ts. Based on this assumption\, we first propose\na bigram CRoss TErm Retri eval (CRTER2) model as the basis model\, and\nthen recursively propose a g eneralized n-gram CRoss TErm Retrieval\n(CRTERn) model for n query terms w here n > 2. \nSpecifically\, a bigram Cross Term occurs when the correspon ding query\nterms appear close to each other\, and its impact can be model ed by the\nintersection of the respective shape functions of the query ter ms. For\nn-gram Cross Term\, we develop several distance metrics with diff erent\nproperties and employ them in the proposed models for ranking. We a lso\nshow how to extend the language model using the newly proposed cross\ nterms. Extensive experiments on a number of TREC collections\ndemonstrate the effectiveness of our proposed models. \n\nBIOGRAPHY:\n\nJIMMY HUANG i s a Professor & Director at the School of Information\nTechnology and the founding director of Information Retrieval &\nKnowledge Management Researc h Lab at the York University. DTSTAMP:20250512T151611Z END:VEVENT END:VCALENDAR