Anomaly and Fraud Detection

Given credit card transaction history, how can we find out anomalous users? How can we detect people involved in voice phishing from bank transaction data? How can we detect anomalous users (e.g., spammers) from online social networks like Twitter or Facebook? In this project, we develop models and algorithms for finding anomalies and frauds. We design a method that is scalable, works in real time, and requires as few parameters as possible.


  • Credit card fraud
  • Voice phishing detection
  • Spammer detection in phone call network
  • Anomalous user detection in social networks


  • Saehan Jo, Jaemin Yoo, and U Kang, "Fast and Scalable Distributed Loopy Belief Propagation on Real-World Graphs", 11th ACM International Conference on Web Search and Data Mining (WSDM) 2018, Los Angeles, CA, USA. [BIBTEX] [HOMEPAGE (CODE, DATA)] [PDF]
  • Yongsub Lim, Minsoo Jung, and U Kang, "Memory-efficient and Accurate Sampling for Counting Local Triangles in Graph Streams: From Simple to Multigraphs", ACM Transactions on Knowledge Discovery from Data (TKDD), vo. 12, issue 1, Feburuary 2018. [BIBTEX] [HOMEPAGE (CODE, DATA)] [PDF]
  • Minsoo Jung, Sunmin Lee, Yongsub Lim, U Kang, "FURL: Fixed-memory and Uncertainty Reducing Local Triangle Counting for Graph Streams", arXiv: 1611.06615 [cs.DS], 26 November 2016. [BIBTEX] [PDF]
  • Yongsub Lim, and U Kang, "MASCOT: Memory-efficient and Accurate Sampling for Counting Local Triangles in Graph Streams", 21st ACM SIGKDD Conference on Knowledge Discovery and Data Mining (KDD) 2015, Sydney, Australia [BIBTEX] [HOMEPAGE (CODE, DATA)] [PDF]
  • U Kang, Brendan Meeder, Evangelos E. Papalexakis, and Christos Faloutsos, "HEigen: Spectral Analysis for Billion-Scale Graphs", IEEE Transactions on Knowledge and Data Engineering (TKDE), vol. 26, no.2, pp. 350-362, Feb. 2014. [BIBTEX] [PDF]
  • Jay Yoon Lee, U Kang, Danai Koutra, and Christos Faloutsos, "Fast anomaly detection despite the duplicates", 22nd International World Wide Web Conference (WWW) 2013, Rio de Janeiro, Brazil. [BIBTEX] [PDF]
  • U Kang, Brendan Meeder, and Christos Faloutsos, "Spectral Analysis for Billion-Scale Graphs: Discoveries and Implementation", Pacific-Asia Conference on Knowledge Discovery and Data Mining (PAKDD) 2011, Shenzhen, China. (acceptance rate 9.7 %) [BIBTEX] [PDF]