I obtained my Ph.D. in Information and Computer Sciences from Bren School of Information & Computer Sciences, Universtity of California Irvine in September 2011. My advisor was Cristina Lopes and my PhD thesis was on Learning to Rank.
Microsoft Bing, Senior RSDE
I work in Bing's core ranking team
|Since Sept 2011|
Microsoft Bing, RSDE Intern
I worked on improving and optimizing Bing's new ranking algorithm.
Microsoft Bing, Software Developer Intern
I worked on the index sorting problem with the Relevance Infrastructure team.
Microsoft Live Search, Software Developer Intern
I worked on extracting statistically significant phrases from the titles and snippets of web search results.
- Y. Ganjisaffar, Tree Ensembles for Learning to Rank, PhD thesis, University of California, Irvine, August 2011 [PDF, Slides].
- Y. Ganjisaffar et al., qSpell: Spelling Correction of Web Search Queries using Ranking Models and Iterative Correction, in Spelling Alteration for Web Search Workshop, Bellevue, WA, USA, July 2011 [PDF].
- Y. Ganjisaffar, T. Debeauvais, S. Javanmardi, R. Caruana, C. Lopes, Distributed Tuning of Machine Learning Algorithms using MapReduce Clusters, KDD 2011 workshop on Large-scale Data Mining, San Diego, CA, USA [PDF, Slides].
- Y. Ganjisaffar, R. Caruana, C. Lopes, Bagging Gradient-Boosted Trees for High Precision, Low Variance Ranking Models, in SIGIR 2011, Beijing, China (19.8% acceptance rate) [PDF, Slides].
- S. Javanmardi, Y. Ganjisaffar, S. Grant, C. Lopes, Statistical Measure of the Effectiveness of the Open Editing Model of Wikipedia, in ICWSM 2010 [PDF].
- S. Javanmardi, Y. Ganjisaffar, C. Lopes, P. Baldi , Scientific Mashups: The Issue of Trust in the Aggregation of Web 2.0 Content, WebScience'2010, Raleigh, NC [PDF].
- Y. Ganjisaffar, S. Javanmardi, C. Lopes, Using User Reviews to Improve Search in Wikipedia, SIGIR 2009 Workshop on Search in Social Media, Boston, USA, 2009 [PDF].
- Y. Ganjisaffar, S. Javanmardi, C. Lopes, Leveraging Crowdsourcing Heuristics to Improve Search in Wikipedia, in Proceedings of the 5th International Symposium on Wikis and Open Collaboration (WikiSym), Florida, USA, 2009 [PDF].
- S. Javanmardi, Y. Ganjisaffar, C. Lopes, P. Baldi, User Contribution and Trust in Wikipedia, Proceedings of The 5th International Conference on Collaborative Computing: Networking, Applications and Worksharing , Washington D.C., USA, 2009 [PDF].
- Y. Ganjisaffar, S. Javanmardi, C. Lopes, Review-based Ranking of Wikipedia Articles, in Proceedings of the International Conference on Computational Aspects of Social Networks, Fontainebleau, France, 2009 [PDF].
- Y. Ganjisaffar, S. Javanmardi, S. Grant, C. Lopes, CalSWIM: A Wiki-based Data Sharing Platform, Collaborative Computing: Networking, Applications and Worksharing, Vol. 10, 2009, pp. 34-43 [PDF].
- Y. Ganjisaffar, H. Abolhassani, Towards a Framework for Brokering Semantic Web Services, International Journal of Computers and their applications (IJCA), Vol. 15, No. 4, December 2008, pp. 252-262 [PDF].
- H. R. Shahriari, Y. Ganjisaffar, R. Jalili, and J. Habibi, Topological Analysis of Multi-Phase Attacks using Expert Systems, International Journal of Information Science and Engineering (JISE), Vol. 24, No. 3, May 2008, pp. 743-767 [PDF].
- M. Neshati, Y. Ganjisaffar and H. Abolhassani, Clustering-based Taxonomy Construction for Semantic Web Services, Proceedings of the 12th International CSI Computer Conference (CSICC 2007), Tehran, Iran [PDF].
- Y. Ganjisaffar, H. Abolhassani and M. Neshati, A Similarity Measure for OWL-S annotated Web Services, Proceedings of The 2006 IEEE/WIC/ACM International Conference on Web Intelligence, Hong Kong, 2006, pp. 621-624 [PDF].
- S. Javanmardi, M. Amini, R. Jalili, and Y. Ganjisaffar, SBAC: Semantic Based Access Control, The 11th Nordic Workshop on Secure IT-systems, Linkping, Sweden, October 2006, pp. 157-168 [PDF].
- Y. Ganjisaffar, H. Abolhassani and R. Jalili, An Architecture for a context-aware Service Broker in Ubiquitous Computing Environments, International Workshop on Pervasive Computing Systems & Application (PerCSA 2006), UAE, March 2006, pp. 1097-1100 [PDF].
- Y. Ganjisaffar, K. Sheykh Esmaili, M. Ghodsi and H. Abolhassani, Parallel Online Ranking of Web Pages, The 4th ACS/IEEE International Conference on Computer Systems and Applications (AICCSA-06), UAE, March 2006, pp. 104-109 [PDF].
- Y. Ganjisaffar, H. Abolhassani, Context-aware Semantic Web Service Brokering, 11th International CSI Computer Conference (CSICC 2006), Jan. 2006, Tehran, Iran [PDF].
- H. Shahriari, Y. Ganjisaffar and R. Jalili, A Connectivity Based Method for Analyzing Network Vulnerabilities, Proceedings of the 3rd Iranian Society of Cryptography Conference (ISCC'05), Isfahan, Iran, Sep. 2005, pp 273-284 (Received best paper award).
- Optimizing an index of web documents. U.S. patent, filed March 2011.
jforests is a Machine Learning framework that includes implementations of popular tree-based learning algorithms (2011)
qSpell: Search Query Spell Correction
Roughly 10-15% of the queries which are sent to web search engines contain spelling errors. This project is an attempt to detect and fix those errors (2011)
The Lasso is a shrinkage and selection method for linear regression. Lasso4j is an open source Java implementation of the Lasso L1-constrained fitting for linear regression. This implementation is based on the glmnet R package which is implemented in Fortran.
crawler4j: An Open Source Web Crawler for Java
A light-weight and very fast web crawler for Java which uses Berkeley DB for managing the frontier queue in a very efficient manner. Crawled the whole English Wikipedia in 10 hours during January 2009.
Wikijoo: A Search Engine for Wikipedia
Wikijoo is a special purpose search engine for Wikipedia which uses a Review-based ranking algorithm in ranking search results (2009).
- Bing Ranking and Intent: Above and Beyond award, March 2012.
- 3rd Prize for Microsoft's Speller Challenge, July 2011 [news story].
- Research grant from Amazon.com for working on "Search Query Spell Correction", March 2011
- Research grant from Amazon.com for working on "Distributed Tuning of Machine Learning Algorithms", Jan 2011
- 6th rank in UCSD Data Mining Competition among more than 90 teams, 2010
- Phd Admission and Fellowship offer from University of Illinois at Urbana Champaign, 2007
- Phd Admission and Fellowship offer for three years from University of California, Irvine, 2007
- PhD Admission with a Fellowship offer for two years of support from University of California, Riverside, 2007.
- Phd Admission and Fellowship offer for two years from University of Alberta, 2007
- 1st Rank in cumulative GPA among M.Sc. students of the department, Fall 2004 beginners, Sharif University of Technology, Fall 2006.
- Best Paper Award, 3rd Iranian Society of Cryptography Conference, ISCC'05, 2005.
- 5th Rank in National Scientific Olympiad in Computer Engineering, Stage II, Tehran, Iran, Summer 2004.
- 2nd Rank in National Scientific Olympiad in Computer Engineering, Stage I, Tehran, Iran, Spring 2004.
- 2nd Rank among over 8,000 students in the National Graduate Entrance Examination in Computer Engineering,
- Accepted in Sharif University of Technology, the best university of Iran.
- Ranked top 0.04% among over 350,000 applicants in Iran's Nationwide University Entrance Examination, Summer 2000.
- 1st Rank in Computer Programming Contest in Kerman Province, 1998.
The followings are incorrect English spellings of my name that I'm putting here just for helping people who want to find me using search engines but don't know the exact spelling: Yaser Ganji Saffar, Yasser Ganji Safar, Yasser Ganji Saffar.