Robert Luk
Associate Professor
BSc & Dip Eng.(Southampton); MSc (Warwick); PhD (Southampton); C.Eng.; C.ITP.;

Research Interests: Information Retrieval, Data Structures and Algorithms, Pattern Recognition, Signal Processing, Natural Language Processing, Chinese Computing, Computational Linguistics


Robert is interested in information retrieval. In 2000, he was a visiting research scholar at the Center for Intelligent Information Retrieval, University of Massachusetts, Amherst, USA. He participated in the NTCIR open IR evaluation and TREC open IR evaluation using a search engine developed by his group. His search engine is being evaluated using terabyte collection at present. He worked and published in various aspects of information retrieval including indexing, retrieval models, term weighting, query expansion, active/relevance feedback, retrieval process, text categorization, spoken document retrieval, XML indexing and retrieval, string search algorithms, search interface and search evaluation. He served as a reviewer or program committee member of various conferences (e.g., ACM SIGIR, ICTIR, ACM CIKM, NLDB, AIRS, IEEE NLPKE, ACL RS Workshop and IJCNLP), and as a reviewer for journals (e.g., ACM TALIP, DKE, DSS, IEEE Signal Processing Letters, IEEE TEC, IEEE TKDE, IEEE TSMC, IJCPOL, IJCSSE, IJNS, IJTS, IJCA, IPM, ISci, JASIST, Neurocomputing and Pattern Recognition) and funding agencies (e.g., UGC). He is on various editorial (review) boards (e.g. IPM). Earlier, he helped to organize conferences (e.g., ISIMP 04 and WAIM 06). He was invited to deliver talks at the IBM Scientific Centre (Winchester), Hong Kong Digital 21 and HKG SIUF seminar. He spent his industrial internship at IBM Hursley, UK. He is an inventor of 8 US/PRC (search related) patents, some of which are licensed. He is a consultant for the Hong Kong Judiciary to develop a search system for bilingual judgements. His works (with his co-workers) have been cited in Wikipedia, books and research monographs (e.g., Connectionist models of memory and language, and Multilingual corpora in teaching and research). He is a recipient of various awards (e.g., technology transfer award, FENG research grant achievement award and Thomas Stephen prize for journal publication). He is listed in various bibliography publications (e.g., Marquis "Who is who" in Science and Engineering). Together with the Hong Kong Society for the Blind, he also jointly developed the world's first, Chinese screen reader (ASAB98) which was licensed to various companies and government organizations, and which was voted as an outstanding event by the Hong Kong Blind Union. He has his share of administrative duties, for example being a member of the Departmental Research Committee. He also takes his own initiatives, like acquiring new equipment (not just to be used for himself or his students, but others [some from another department] too). He has taught over 20 different subjects at postgraduate, undergraduate and sub-degree levels (e.g., information retrieval, financial computing, data structures and algorithms, etc.). His graduated students include Kelvin Hung (M.Phil.), W.S. Wong (M.Phil.), Edward Dang (Ph.D.) and Jack Wu (Ph.D.). He has also served as an external examiner for Ph.D. candidates of CUHK and HKUST. He is a senior member of the ACM (Life) and its SIGIR, a senior member of the IEEE, and a chartered fellow of the BCS (Life) and its IRSG (affiliated member). Note that he believes that computer science and information retrieval are science.

Selected Publications
  1. Dang, E.K.F., R.W.P. Luk and J. Allan (2016) "Context-dependent relevance model", Journal of the Association for Information Science and Technology 67(3): 582-593.
  2. Dang, E.K.F., R.W.P. Luk and J. Allan (2015) "Fast forward index methods for pseudo-relevance feedback retrieval", ACM Trans. on Information Systems 33(4): Article No. 19.
  3. Dang, E.K.F., R.W.P. Luk and J. Allan (2014) "Beyond bag-of-words: Bigram-enhanced context-dependent term weights", Journal of the Association for Information Science and Technology 65(6): 1134-1148.
  4. Wu, H.C., R.W.P. Luk, K.F. Wong and J.Y. Nie (2012) "A split-list approach for relevance feedback in information retrieval", Information Processing & Management 48(5): 969-977.
  5. Luk, R.W.P. (2011) Scalable, statistical storage allocation for extensible inverted file construction. Journal of Systems and Software 84(7): 1082-1088.
  6. Luk, R.W.P. (2010) "Understanding scientific study via process modeling", Foundations of Science 15(1): 49-78.
  7. Dang, E.K.F., H.C. Wu, R.W.P. Luk and K.F. Wong (2009) "Building a framework for the probability ranking principle by a family of expected weighted rank". ACM Trans. on Information Systems 27(4): Article No. 20.
  8. Dang, E.K.F., R.W.P. Luk, K.S. Ho, D.L. Lee and S.C.F. Chan (2009) "Optimal Combination of Nested Clusters by a Greedy Approximation Algorithm", IEEE Trans. on Pattern Analysis and Machine Intelligence 31(11): 2083-2087.
  9. Luk, R.W.P. (2008) On event space and rank equivalence between probabilistic retrieval models. Information Retrieval 11(6): 539-561.
  10. Ho, E.K.S., H.V. Leong, W. Lam and R.W.P. Luk (2006) "Integrating XML and CORBA to support collaborative writing using off-the-shelf editing software", Information Systems 31(6): 465-488.
  11. Luk, R.W.P. and R.I. Damper (2006) "Non-parametric linear time-invariant system identification by discrete wavelet transforms", Digital Signal Processing 16(3): 303-319.
  12. Hung, K.Y., R.W.P. Luk, D.S. Yeung, F.L. Chung and W. Shu (2005) "A multiple classifier approach to detect Chinese character recognition errors", Pattern Recognition 38(5): 723-738.
  13. Wong, W.S., R.W.P. Luk and E.K.S. Ho (2005) "Discovering title-like terms", Information Processing and Management 41(4):789-800.
  14. Luk, R.W.P., B.K.Y. T'sou, T.B.Y. Lai, O.Y. Kwong, F.C.Y. Chik and L.Y.L. Cheung (2003) "Bilingual document retrieval and management using XML", Software: Practice and Experience 33(1): 41-59.
  15. Luk, R.W.P., H.V. Leong, T.S. Dillon, Alvin T. S. Chan, W. B. Croft and J. Allan (2002) "A survey in indexing and searching XML documents", Journal of the American Society for Information Science and Technology 53(6): 415-437.
  16. Luk, R.W.P. (2001) "Compact morphic directed acyclic word graph", The Computer Journal 44(5): 425-434.
  17. Lau, K. and R.W.P. Luk (1999) "Word sense classification by hierarchical clustering", Journal of Chinese Language and Computing 9(1), 101-121.
  18. Luk, R.W.P. and R.I. Damper (1998) "Computational complexity of a fast Viterbi decoding algorithm for stochastic letter-phoneme transduction", IEEE Trans. Speech and Audio Processing 6(3): 217-225.
  19. Luk, R.W.P. and R.I. Damper (1996) "Stochastic phonographic transduction for English", Computer Speech and Language 10: 133-153.
  20. Luk, R.W.P. and R.I. Damper (1993) "Inference of letter-phoneme correspondences with pre-defined consonant and vowel pattern", Proc. IEEE ICASSP '93, Vol 2, Minneapolis, MN, USA, pp. II-203-II-206.