Recent Positions
LinkedIn Corportation
Director of Engineering, AI, 2020 – Present
- As a manager, I lead multiple teams of ML engineers and applied researchers, driving AI solutions for Talent Solutions and LinkedIn China. For Talent Solutions, we support products such as Job Search, Job-You-May-Be-Interested-In (JYMBII), Guest Search, Recruiter Search, Recommended Matches, and Instant Notifications. For LinkedIn China, we support a job-seeking based user experience for the local market.
- As a senior AI leader, working closely with senior partners in product and engineering to shape LinkedIn’s vision in Talent Solutions and LinkedIn China, building cross-functional teams, with the product, data science, and infrastructure to streamline innovation.
- From 2020 – 2021, I also briefly led AI team for Sales Solutions.
Etsy Inc.
Director of Engineering, Data Science and Machine Learning, 2016 – 2020
- As a manager, I grow an organization of multiple teams from 5 to almost 40 Master and Ph.D. level Data Scientists and Machine Learning Engineers, located in New York City and San Francisco offices, with backgrounds in Computer Science, Operation Research, Electrical Engineering, Statistics, Economics, Physics and others, including graduates from Harvard University, Cornell University, Carnegie Mellon University and others. My reports include several front-line managers and one architect, both grown internally and hired externally.
- As a department head, I work with senior leaders in the company (e.g., VP of Engineering, CTO and others) to develop strategies for cross-functional collaboration to incorporate Machine Learning as a key element in product development, complementing Design, Analytics, UX Research, and Product Engineering.
- As a technical leader, I drive Machine Learning and Data Science vision and deliver cutting-edge scientific solutions for Search & Discovery, Personalization & Recommendation and Computational Advertising by utilizing a wide range of technologies such as deep learning, probabilistic modeling, image understanding (computer vision), user profiling, query understanding, text mining and others. Results are published in SIGIR 2018, WSDM 2019, KDD 2019 and other venues.
Yahoo Research
Senior Manager of Research, Search and Personalization Sciences, 2013 – 2016
- Design and build a large-scale machine learning system to power the next generation card-driven mobile search experiences for millions of users, utilizing learning-to-rank, deep learning and causal inference techniques. 4 patents filed.
- Build large-scale ranking models to personalize Yahoo homepage content items for billions of U.S. users and improve 10% over a major user engagement metric (usually 1% considered as significant), utilizing ensemble methods, tree-based models and online learning. 2 publications with 1 Best Paper Award in prestige conferences and 4 internal publications.
- Build large-scale ranking models to personalize Yahoo homepage content items for millions of users in 20+ international markets with 20% improvements over a major user engagement metric (usually 2% considered as significant), utilizing ensemble methods, tree-based models and multi-armed bandit algorithms.
- Build large-scale statistical models to track and predict click-through-rate (CTR) of native streaming ads with 2% improvements over a multi-year production system, utilizing generalized linear models and online learning.
Education
- Lehigh University
Ph.D. in Computer Science, August 2007 – May 2013 - Lehigh University
M.S. in Computer Science, August 2007 – May 2010 - Beijing University Of Chemical Technology (BUCT)
B.S. in Computer Science, September 2003 – June 2007
Patents
- US Patent US11132700B1: “Identifying Direct and Indirect Effects in A/B Tests“. Sept 28, 2021.
- US Patent US20180011854A1: “Method and System for Ranking Content Items based on User Engagement Signals“. Jan 11, 2018.
- US Patent US20170344552A1: “Computerized System and Method for Optimizing the Display of Electronic Content Card Information when Providing Users Digital Content“. Nov 30. 2017.
- US Patent US20170098283A1: “Methods, Systems
and Techniques for Blending Online Content From Multiple Disparate Content Sources Including a Personal Content Source or a Semi-Personal Content Source“. Apr 6, 2017. - US Patent US20170097933A1: “Methods, Systems
and Techniques for Ranking Blended Content Retrieved from Multiple Disparate Content Sources“. Apr 6. 2017.
Selected Publications
- Z. Wang, X. Yin, T. Li, and L. Hong. Causal Meta-Mediation Analysis: Inferring Dose-Response Function From Summary Statistics of Many Randomized Experiments. In Proceedings of the 26th ACM SIGKDD International Conference on Knowledge Discovery & Data Mining (KDD 2020). Virtual Event, August 2020. (Full Paper, 16% Acceptance) [DOI] [Local Copy]
- R. Guo, X. Zhao, A. Henderson, L. Hong, and H. Liu. Debiasing Grid-based Product Search in E-commerce. In Proceedings of the 26th ACM SIGKDD International Conference on Knowledge Discovery & Data Mining (KDD 2020). Virtual Event, August 2020. (Full Paper, 16% Acceptance) [DOI] [Local Copy]
- J. Wang, K. Ding, L. Hong, H. Liu, and J. Caverlee. Next-item Recommendation with Sequential Hypergraphs. In Proceedings of the 43rd International ACM SIGIR Conference on Research and Development in Information Retrieval (SIGIR 2020), Virtual Event, July 2020. (Full Paper, 26% Acceptance) [DOI]
- J. Wang, R. Louca, D. Hu, C. Cellier, J. Caverlee and L. Hong. Time to Shop for Valentine’s Day: Shopping Occasions and Sequential Recommendation in E-commerce. In Proceedings of the 13th ACM International Conference on Web Search and Data Mining (WSDM 2020), Houston, Texas, Feb, 2020. (Full Paper, 15% Acceptance) [Local Copy] [DOI]
- X. Yin and L. Hong. The Identification and Estimation of Direct and Indirect Effects in A/B Tests through Causal Mediation Analysis. In Proceedings of the 25th SIGKDD Conference on Knowledge Discovery and Data Mining (KDD 2019), Anchorage, Alaska, August, 2019. (Full Paper, Oral Presentation, 6.4% Acceptance) [Local Copy] [DOI]
- H. Jiang, A. Sabharwal, A. Henderson, D. Hu and L. Hong. Understanding the Role of Style in E-commerce Shopping.In Proceedings of the 25th SIGKDD Conference on Knowledge Discovery and Data Mining (KDD 2019), Anchorage, Alaska, August, 2019. (Full Paper, 20% Acceptance) [Local Copy] [DOI]
- N. Ju, D. Hu, A. Henderson and L. Hong. A Sequential Test for Selecting the Better Variant – Online A/B testing, Adaptive Allocation, and Continuous Monitoring. In Proceedings of the 12th ACM International Conference on Web Search and Data Mining (WSDM 2019), Melbourne, Australia, Feb, 2019. (Full Paper, 16% Acceptance) [Local Copy]
- L. Wu, D. Hu, L. Hong and H. Liu. Turning Clicks into Purchases: Revenue Optimization for Product Search in E-Commerce. In Proceedings of the 41st International ACM SIGIR Conference on Research and Development in Information Retrieval (SIGIR 2018), Ann Arbor, Michigan, U.S.A. July 8-12, 2018. (Full Paper, 21% Acceptance) [Local Copy] [DOI]
- T. Chen, Y. Sun, Y. Shi and L. Hong. On Sampling Strategies for Neural Network-based Collaborative Filtering. In Proceedings of the 23rd SIGKDD Conference on Knowledge Discovery and Data Mining (KDD 2017), Halifax, Nova Scotia, August, 2017. (Full Paper, 17% Acceptance) [Local Copy] [Local Supplementary] [DOI]
- Q. Zhao, Y. Shi and L. Hong. GB-CENT: Gradient Boosted Categorical Embedding and Numerical Trees. In Proceedings of the 26th International Conference on World Wide Web (WWW 2017), Perth, Australia, April, 2017. (Full Paper, 17% Acceptance) [Local Copy] [DOI]
- X. Yi, L. Hong, E. Zhong, NN. Liu and S. Rajan. Beyond Clicks: Dwell Time in Personalization. In Proceedings of the 8th ACM Conference on Recommender Systems (RecSys 2014), Foster City, Silicon Valley, USA, October, 2014. (Full Paper, 23% Acceptance) [Local Copy] [DOI] Best Paper Award
- A. Ahmed, L. Hong and A. Smola. Nested Chinese Restaurant Franchise Process: Applications to User Tracking and Document Modeling. In Proceedings of the 30th International Conference on Machine Learning (ICML 2013), Atlanta, GA, May, 2013. [PDF] [Supplementary]
- A. Ahmed, L. Hong and A. Smola. Hierarchical Geographical Modeling of User Locations from Social Media Posts. In Proceedings of the 22nd International Conference on World Wide Web (WWW 2013), Rio de Janeiro, Brazil, May, 2013. [Local Copy] [DOI]
- L. Hong, A. Doumith and B. D. Davison. Co-Factorization Machines: Modeling User Interests and Predicting Individual Decisions in Twitter. In Proceedings of the 6th ACM International Conference on Web Search and Data Mining (WSDM 2013), Rome, Italy, Feb, 2013. [Local Copy] [DOI] Best Paper Nominated
- L. Hong, A. Ahmed, S. Gurumurthy, A. Smola and K. Tsioutsiouliklis. Discovering Geographical Topics in the Twitter Stream. In Proceedings of the 21st International Conference on World Wide Web (WWW 2012), Lyon, France, 2012. [Local Copy] [DOI] [Slides]
- L. Hong, O. Dan
and B. D. Davison. Predicting Popular Messages in Twitter [Poster]. In Proceedings of the 20th international conference on World Wide Web (WWW 2011), Hyderabad, India. [Local Copy] [DOI] Best Poster Award
Selected Talks & Presentations
- Invited Talk at Melbourne Search and Recommendation Group Meetup about “Computational Jobs Marketplace“, Virtual Event, November 2021, [Slides]
- Invited talk at at The AI Summit | Silicon Valley about “Computational Jobs Marketplace“, Virtual Event, November 2021. [Slides]
- Invited Talk at Booking.com about “Recent Challenges and Advances in Industrial Recommender Systems“, Virtual Event, December 2020. [Slides]
- Keynote Talk at First International Workshop on Industrial Recommendation Systems at KDD 2020, Virtual Event. [Slides]
- Tutorial “Online User Engagement: Metrics and Optimization” at KDD 2020, Virtual Event. [Slides]
- “Recent Advances and Challenges in E-Commerce Search & Recommendation Systems” at Southern Data Science Conference, Virtual Event, August 2020. [Slides]
- Invited Talk “Recent Advances and Challenges in E-Commerce Search and Recommendation Systems” at WSDM 2020 Industrial Day Houston, Texas, Feb 2020. [Slides]
- Tutorial “Online User Engagement: Metrics and Optimization” at WWW 2019, San Francisco, CA, May 2019. [Slides]
- Keynote Talk “Search for E-Commerce: (Not) Solved (Yet).” at The 2018 SIGIR Workshop On eCommerce, Ann Arbor, Michigan, July 2018. [Slides]
- “Turning Clicks into Purchases” at Machine Learning Innovation Summit, San Francisco, CA, May 2018. [Slides]
- “Happy for Two (or Three) Joint Revenue Optimization for 2-Sided Parties for Promoted Listings” at WSDM 2018‘s Workshop on Two-sided Marketplace Optimization: Search, Pricing, Matching & Growth, Los Angeles, CA, Feb 2018. [Slides]
- Tutorial “Tutorial on Metrics of User Engagement” at WSDM 2018, Los Angeles, CA, Feb 2018. [Slides]
- “AI for Search in E-Commerce” at AICon 2018
about , Beijing, China, Jan 2018. [Slides] - “A Gradient-based Framework for Personalization” at Data Science Invited Talk Series, Indiana University at Bloomington, IN, November 2017. [Slides] [Video]
- “A Gradient-based Framework for Personalization” at Global Artificial Intelligence Conference, New York, NY, October 2017. [Slides]
- “GB-CENT: Gradient Boosted Categorical Embedding and Numerical Trees” at Big Data Innovation Summit Boston
2017 , Boston, MA, September 2017. [Slides] - “AI in E-Commerce at Etsy” at Insights Data Science, New York City, NY, August 2017. [Slides]
- “AI in E-Commerce at Etsy” at Machine Learning Summit, Beijing, China, June 2017. [Slides]
- “GB-CENT: Gradient Boosted Categorical Embedding and Numerical Trees” at Chinese Academy of Sciences, Beijing, China, June 2017. [Slides]
- “GB-CENT: Gradient Boosted Categorical Embedding and Numerical Trees” at Data Science Pop-up, New York City, NY, June 2017. [Slides]
- “GB-CENT: Gradient Boosted Categorical Embedding and Numerical Trees” at Machine Learning Innovation Summit, San Francisco, CA, June 2017. [Slides]
- “GB-CENT: Gradient Boosted Categorical Embedding and Numerical Trees” at CSE Dept. at Lehigh University, Bethlehem, PA, April 2017. [Slides]
- “GB-CENT: Gradient Boosted Categorical Embedding and Numerical Trees” at Global Predictive Analytics Conference, Santa Clara, CA, March 2017. [Slides]
- “GB-CENT: Gradient Boosted Categorical Embedding and Numerical Trees” at Predictive Analytics Innovation Summit, San Diego, CA, Feb. 2017. [Slides]
- “Personalization@Yahoo” at RED(小红书), Shanghai, China, June 2016.”Beyond Clicks: Dwell Time in Personalization” at Twitter, San Francisco, CA, June 2015.
Selected Awards and Honors
- Yahoo Patent Milestone Award 2016
- RecSys Best Paper Award 2014
- WSDM Best Paper Nominated 2013
- Dean’s Teaching Assistantship & Research Assistantship 2012
- Rossin Doctoral Fellows 2012
- KDD Student Travel Grant 2011
- WWW Best Poster Award 2011
Selected Professional Activities
Organizer:
The First International Workshop on Computational Jobs Marketplace at WSDM 2022.
Tutorial “Online User Engagement: Metrics and Optimization” at KDD 2020
Tutorial “Online User Engagement: Metrics and Optimization” at WWW 2019
DAPA: The Workshop on Deep Matching in Practical Applications at WSDM 2019
Tutorial on Metrics of User engagement — Applications to Search & E-Commerce at WSDM 2018
The Second Workshop on User Engagement Optimization at KDD 2014
The First Workshop on User Engagement Optimization at CIKM 2013
Session Chair:
SIGIR 2018, WSDM 2014
Senior Program Committee:
The Web Conference 2022, WSDM 2022, KDD 2021, WSDM 2021, WSDM 2020
Program Committee:
CIKM2021, SIGIR 2021, CIKM 2020, KDD 2020, SIGIR 2020, The Web Conference 2020, CIKM 2019, KDD 2019, RecSys 2019, SIGIR 2019, The Web Conference 2019, WSDM 2019, CIKM 2018, KDD 2018, SIGIR 2018, WWW 2018, WSDM 2018, CIKM 2017, SIGIR 2017, WSDM 2017, WWW 2017, CIKM 2016, KDD 2016, SIGIR 2016, WWW 2016, WSDM 2016, IJCAI 2016, ACL 2016, EMNLP 2016, CIKM 2015, SIGIR 2015, KDD 2015, IUI 2015, WWW 2015, AIRS 2015, CIKM 2014, SIGIR 2014, WSDM 2014, AAAI 2014, IEEE ICCC 2014 SNBD, ICWSM 2013, EMNLP-CoNLL 2012
The 2nd Workshop of Heterogeneous Information Access at SIGIR 2016, The 6th International Workshop on Social Recommender Systems (SRS 2015) at KDD 2015, The 1st Workshop on Offline and Online Evaluation of Web-based Services at WWW 2015, The 5th International Workshop on Social Recommender Systems (SRS 2014) at WWW 2014, The 2nd International Workshop on Mining Social Network Dynamics (MSND) at WWW 2013
Journal Editorial Board
Data Mining and Management, Frontiers in Big Data
Journals Review:
Data Mining and Knowledge Discovery
ACM Transactions on Knowledge Discovery from Data
ACM Transactions on Intelligent Systems and Technology
ACM Transactions on Information Systems
Neurocomputing
IEEE Transactions on Neural Networks and Learning Systems
IEEE Intelligent Systems
IEEE Transactions on Knowledge and Data Engineering
IEEE Transactions on Systems, Man, and Cybernetics
IEEE Transactions on Services Computing
IEEE Transactions on Big Data
Information Processing and Management
Journal of the Association for Information Science and Technology
Journal of Computer Science and Technology
Journal of Systems Science and Systems Engineering
Information Systems
GeoInformatica
Mentorship
- Ziqiao Guan — Stony Brook University (2020 Summer)
- Md Mehrab Tanjim — University of California at San Diego (2019 Summer)
- Saket Gurukar — The Ohio State University (2019 Summer)
- Jianling Wang — Texas A & M University (2019 Summer)
- Zenan Wang — University of California at Berkeley (2019 Summer)
- Ruocheng Guo — Arizona State University (2019 Summer)
- Amin Javari —
University of Illinois at Urbana-Champaign (2018 Summer) - Hao Cui — Tufts University (2018 Summer) -> Google
- Nianqiao Ju — Harvard University (2018 Summer)
- Liang Wu — Arizona State University (2017 Summer) -> Airbnb
- Wei Qian — Cornell University (2017 Summer)
- Qian Zhao — University of Minnesota (2016 Summer) -> Bloomberg
- Qingyun Wu — University of Virginia (2016 Summer)
- Yue Ning — Virginia Tech University (2016 Summer) -> Stevens Institute of Technology
- Ting Chen — Northeastern University (2016 Summer) -> UCLA -> Google
- Jay-Yoon Lee — Carnegie Mellon University (2015 Summer)
- Shalmali Joshi —
University of Texas at Austin (2015 Summer) -> Vector Institute - Mingjie Qian — University of Illinois at Urbana-Champaign (2014 Summer) -> Yahoo Labs -> Microsoft
Collaborators
- Kamelia Aryafar, Etsy -> Overstock.com -> Google
- Yue Shi, Yahoo Labs -> Facebook
- Nathan N. Liu, Yahoo Labs -> Google -> Startup -> Google -> Startup->LinkedIn
- Suju Rajan, Yahoo Labs -> Criteo -> LinkedIn
- Erheng Zhong, Yahoo Labs -> Baidu Research (USA) -> Facebook -> Startup
- Brian D. Davison, Lehigh University
- Dawei Yin, Lehigh University -> Yahoo Labs -> JD.com -> Baidu
- Ovidiu Dan, Lehigh University -> Bing (Microsoft)
- Zaihan Yang, Lehigh University -> Wayne State University -> Northeastern University
- Zhenzhen Xue, Lehigh University -> Google
- Byron Dom, Yahoo Labs -> (Retired)
- Siva Gurumurthy, Yahoo Labs -> Twitter -> KeepTruckin
- Kostas Tsioutsiouliklis, Yahoo Labs -> Twitter -> Yahoo Labs
- Alex Smola, Yahoo Labs -> Google Research -> CMU -> Amazon
- Amr Ahmed, Yahoo Labs -> Google Research
- Marco Pennacchiotti, Yahoo Labs -> eBay Labs -> BMW Group
- Jian Guo, Harvard University -> Walmart Lab -> Startup(s)
- Ron Bekkerman, LinkedIn -> Carmel Ventures -> Cherre