BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20251109T060923EST-7270DuNA6A@132.216.98.100 DTSTAMP:20251109T110923Z DESCRIPTION:Title: Imbalanced learning using actuarial modified loss functi on in tree-based models\n\nAbstract:\n\nTree-based models have gained mome ntum in insurance claim loss modeling\; however\, the point mass at zero a nd the heavy tail of insurance loss distribution pose the challenge to app ly conventional methods directly to claim loss modeling. With a simple ill ustrative dataset\, we first demonstrate how the traditional tree-based al gorithm’s splitting function fails to cope with a large proportion of data with zero responses. To address the imbalance issue presented in such los s modeling\, this paper aims to modify the traditional splitting function of Classification and Regression Tree (CART). In particular\, we propose t wo novel actuarial modified loss functions\, namely\, the weighted sum of squared error and the sum of squared Canberra error. These modified loss f unctions impose a significant penalty on grouping observations of non-zero response with those of zero response at the splitting procedure\, and thu s significantly enhance their separation. Finally\, we examine and compare the predictive performance of such actuarial modified tree-based models t o the traditional model on synthetic datasets that imitate insurance loss. The results show that such modification leads to substantially different tree structures and improved prediction performance.\n\n\n Speaker\n\n\nZhi yu (Frank) Quan is an Assistant Professor at the Department of Mathematics of the University of Illinois at Urbana-Champaign. He holds a Ph.D. in Ac tuarial Science from the University of Connecticut. Before joining Illinoi s\, he worked for a cutting-edge Insurtech company as a R & D data scienti st developing data-driven solutions for major insurance companies. He has a broad spectrum of research interests in data science applications in ins urance such as tree-based models\, natural language processing\, deep lear ning\, and applies his actuarial expertise to build predictive models for claim research\, rate making\, etc.\n\n \n\nhttps://mcgill.zoom.us/j/83436 686293?pwd=b0RmWmlXRXE3OWR6NlNIcWF5d0dJQT09\n\nMeeting ID: 834 3668 6293\n \nPasscode: 12345\n\n\n \n \n  \n \n \n\n DTSTART:20211008T193000Z DTEND:20211008T203000Z SUMMARY:Zhiyu Quan (University of Illinois at Urbana-Champaign) URL:/mathstat/channels/event/zhiyu-quan-university-ill inois-urbana-champaign-333987 END:VEVENT END:VCALENDAR