Thursday, July 26, 2007

Google allows data binging for researchers

Google now opened access to university researchers to its search and MT systems in today's announcement on their research blog. The search API documentation does not mention any restriction on the number of queries that can be posted for search (The earlier limit was 1000). Whatever the number is I am guessing it will be large (Drinking from the firehose?). However, the MT API allows 1000 queries per day with the documentation hinting that this need not be a hard limit.

Looking at the search API output, two things I really miss is the number of hits and the snippet for each search result. The number of hits has been used in several papers for interesting results. The other useful feature is snippets. Every search result from Google is accompanied by a small snippet extracted from the page, as shown below for an example query "Dekang Lin".

The information in the snippets can be used as informative features in different tasks like this one in person name disambiguation. (BTW, Dekang is now at Google)

Despite these minor quibbles, these new APIs will be quite useful to all of us and will certainly result in more papers on Googleology.

Later addition: Turns out we can sort of get the counts by simply counting the number of search results by repeatedly executing the request (only ten results per request) but the API caps this limit to 100. That means you could get a maximum of 1000 results. Which is not quite the same as "Results 1 - 10 of about 779,000,000". Though that number is approximate, it is still indicative of how strong the query is w.r.t the web. For example GoogleCount("Horse+animal") >> GoogleCount("Horse+truck").

Tuesday, July 24, 2007

Readings from SIGIR 2007

SIGIR 2007 is happening now at Amsterdam!

Latent Concept Expansion Using Markov Random Fields, Donald Metzler, Bruce Croft

Random Walks on the Click Graph, Nick Craswell, Martin Szummer

Towards Automatic Extraction of Event and Place Semantics from Flickr Tags, Tye Rattenbury, Nathaniel Good, Mor Naaman

Clustering of Documents with Local and Global Regularization, Fei Wang, Changshui Zhang, Tao Li

Detecting, Categorizing and Clustering Entity Mentions in Chinese Text, Wenjie Li, Donglei Qian, Chunfa Yuan, Qin Lu

Principles of Hash-based Text Retrieval, Benno Stein

DiffusionRank: A Possible Penicillin for Web Spamming, Haixuan Yang, Irwin King, Michael R. Lyu

Context Sensitive Stemming for Web Search, Fuchun Peng, Nawaaz Ahmed, Xin Li, Yumao Lu

Combining Content and Link for Classification using Matrix Factorization, Shenghuo Zhu, Kai Yu, Yun Chi, Yihong Gong

ARSA: A Sentiment-Aware Model for Predicting Sales Performance Using Blogs, Yang Liu, Jimmy Huang, Aijun An, Xiaohui Yu

Heavy-Tailed Distributions and Multi-Keyword Queries, Arnd Konig, Surajit Chaudhuri, Liying Sui, Kenneth Church

Monday, July 23, 2007

Readings from AAAI 2007

AAAI 2007 is now going on at Vancouver. Here is my selection of NLP and Learning papers I would like to know more about.

Deriving a Large-Scale Taxonomy from Wikipedia, Simone Paolo Ponzetto, Michael Strube

Relation Extraction from Wikipedia Using Subtree Mining, Dat P. T. Nguyen, Yutaka Matsuo, Mitsuru Ishizuka

Finding Related Pages Using Green Measures: An Illustration with Wikipedia, Yann Ollivier, Pierre Senellart

Graph Partitioning Based on Link Distributions, Bo Long, Mark (Zhongfei) Zhang, Philip S. Yu

Semi-supervised Learning by Mixed Label Propagation, Wei Tong, Rong Jin

Semi-Supervised Learning with Very Few Labeled Training Examples, Zhi-Hua Zhou, De-Chuan Zhan, Qiang Yang

Clustering with Local and Global Regularization, Fei Wang, Changshui Zhang, Tao Li

Isometric Projection, Deng Cai, Xiaofei He, Jiawei Han

Improving Similarity Measures for Short Segments of Text, Wen-tau Yih, Christopher Meek

Topic Segmentation Algorithms for Text Summarization and Passage Retrieval: An Exhaustive Evaluation, Gaël Dias, Elsa Alves. José Gabriel Pereira Lopes

Robust Estimation of Google Counts for Social Network Extraction, Yutaka Matsuo, Hironori Tomobe, Takuichi Nishimura

Harvesting Relations from the Web - Quantifiying the Impact of Filtering Functions, Sebastian Blohm, Philipp Cimiano, Egon Stemle

Template-Independent News Extraction Based on Visual Consistency, Shuyi Zheng, Ruihua Song, Ji-Rong Wen

Comprehending and Generating Apt Metaphors: A Web-driven, Case-based Approach to Figurative Language, Tony Veale, Yanfen Hao

Mobile Service for Reputation Extraction from Weblogs - Public Experiment and Evaluation, Takahiro Kawamura, Shinichi Nagano, Masumi Inaba, Yumiko Mizoguchi

The Impact of Time on the Accuracy of Sentiment Classifiers Created from a Web Log Corpus, Kathleen T. Durant, Michael D. Smith

Nectar: Learning by Combining Observations and User Edits, Vittorio Castelli, Lawrence Bergman, Daniel Oblinger

Multi-Label Learning by Instance Differentiation, Min-Ling Zhang, Zhi-Hua Zhou

Extracting Influential Nodes for Information Diffusion on a Social Network, Masahiro Kimura, Kazumi Saito, Ryohei Nakano

Temporal and Information Flow Based Event Detection from Social Text Streams, Qiankun Zhao, Prasenjit Mitra, Bi Chen

Analyzing Reading Behavior by Blog Mining, Tadanobu Furukawa, Mitsuru Ishizuka, Yutaka Matsuo, Ikki Ohmukai, Koki Uchiyama

Wednesday, July 18, 2007

Reading List from KDD 2007

KDD 2007 will be on Aug 12-15 in the neighborhood at San Jose. Here is my selection:

"Extracting Semantic Relations from Query Logs", Ricardo Baeza-Yates and Alessandro Tiberi

"Efficient Incremental Clustering with Constraints", Ian Davidson, S.S. Ravi, and Martin Ester

"A Probabilistic Framework for Relational Clustering", Bo Long, Zhongfei Zhang, and Philip S. Yu

"Tracking Multiple Topics for Finding Interesting Articles", Raymond Pon, Alfonso Cardenas, David Buttler, and Terence Critchlow

"Feature Selection Methods for Text Classification", Anirban Dasgupta, Petros Drineas, Boulos Harb, Vanja Josifovski, and Michael Mahoney

"Hierarchical Mixture Models: a Probabilistic Analysis", Mark Sandler

"Information distance from a question to an answer", Xian Zhang, Yu Hao, Xiaoyan Zhu, and Ming Li

"Statistical Change Detection for Multi-Dimensional Data", Xiuyao Song, Mingxi Wu, Chris Jermaine, and Sanjay Ranka

"Constraint-Driven Clustering", Rong Ge, Martin Ester, Wen Jin, and Ian Davidson

"Enhancing Semi-Supervised Clustering: A Feature Projection Perspective", Wei Tang, Hui Xiong, Shi Zhong, and Jie Wu

Tuesday, July 17, 2007

NLP in India?

I was surprised to see

... because NLP is so underdeveloped in India, even undergraduate-level projects may be contributing to the cutting edge of research.
Turns out he was referring to this post from an undergrad which tries to give "the Indian perspective", rather inaccurately. Having worked on NLP at one of the IITs I am compelled to write from a grad student perspective. Sunayana's post is interesting as it brings out several issues in Indic computing.

1. Lack of annotation data - corpora, treebanks, and aligned texts which are sinews and bones of any language processing system. Resources exist, largely due to the efforts of CIIL, various universities and other government agencies but these are dwarfed compared to resources that exist for other languages, like English or the European languages.

However, the rich morphology in Indian languages can be exploited to mitigate the amount of annotation data required for certain tasks, for instance POS tagging.

2. Encoding issues - As rightly pointed by Sunayana, before the adoption of unicode, several data sources were locked up in the fonts they use. But things are changing, there is more and more Indian language content in unicode today than ever. Websites like BBC and Wikipedia are spewing out a lot of content in unicode for those interested in collecting monolingual, comparable corpora. A cursory glance at Wikipedia statistics shows the number of articles in, say Hindi or Tamil for example, has more than doubled in the past six months.

3. Visibility - While there has been an increasing trend to publish in reputed conferences like ICML or ACL, more participation is certainly desirable. IJCAI 2007 was held in India and I highly recommend, if you are around, to submit (sub. deadline: Jul 31st) and/or attend IJCNLP 2008.

This is an exciting time to do NLP research on Indian languages. There is both corporate as well as government motivations which translate to grants and support to universities. The group at IIT Bombay, for example, implemented and deployed, local language based systems for helping farmers. Similar efforts have been taken by other institutes. Microsoft research at Bangalore, and IBM research at New Delhi and Bangalore are working on various projects on Indian Languages, including speech recognition.

At the end of all this, I must partially agree with the quote I made from Alex's blog. Yes, some undergrads do make brilliant contributions which is just because of what they have in their bones. This is true for any country or university.

Effect of Spouses on PhD

Joseph Price studies the effect of marriage on graduation in his paper, "Does a Spouse Slow You Down?: Marriage and Graduate Student Outcomes".

Here is a quick abstract:

Using data on 11,000 graduate students from 100 departments over a 20 year period, I test whether graduate student outcomes (graduation rates, time to degree, publication success, and initial job placement) differ based on a student’s gender and marital status. I find that married men have better outcomes across every measure than single men. Married women do no worse than single women on any measure and actually have more publishing success and complete their degree in less time. The outcomes of cohabiting students generally fall between those of single and married students.

Monday, July 2, 2007

Papers from COLT: Occam's Hammer

John Langford recommends:

Gilles Blanchard and François Fleuret, Occam’s Hammer. When we are interested in very tight bounds on the true error rate of a classifier, it is tempting to use a PAC-Bayes bound which can (empirically) be quite tight. A disadvantage of the PAC-Bayes bound is that it applies to a classifier which is randomized over a set of base classifiers rather than a single classifier. This paper shows that a similar bound can be proved which holds for a single classifier drawn from the set. The ability to safely use a single classifier is very nice. This technique applies generically to any base bound, so it has other applications covered in the paper.

ICML 2007 reading list

Some papers I would like reading right away:

Discriminative Learning for Differing Training and Test Distributions

Steffen Bickel - Max Planck Institute for Computer Science, Germany
Michael Brüeckner - Max Planck Institute for Computer Science, Germany
Tobias Scheffer - Max Planck Institute for Computer Science, Germany

Sparse Eigen Methods by D.C. Programming
Bharath Sriperumbudur - University of California, San Diego, USA
David Torres - University of California, San Diego, USA
Gert Lanckriet - University of California, San Diego, USA

Graph Clustering With Network Structure Indices
Matthew J. Rattigan - University of Massachusetts Amherst, USA
Marc Maier - University of Massachusetts Amherst, USA
David Jensen - University of Massachusetts Amherst, USA

Fast and Effective Kernels for Relational Learning from Texts
Alessandro Moschitti - University of Trento, Italy
Fabio Massimo Zanzotto - University of Rome, Italy

Three New Graphical Models for Statistical Language Modelling
Andriy Mnih - University of Toronto, Canada
Geoffrey Hinton - University of Toronto, Canada

Simple, Robust, Scalable Semi-supervised Learning via Expectation Regularization
Gideon S. Mann - University of Massachusetts, USA
Andrew McCallum - University of Massachusetts, USA

The Rendezvous Algorithm: Multiclass Semi-Supervised Learning with Markov Random Walks
Arik Azran - University of Cambridge, UK

Information-Theoretic Metric Learning (one of the best paper awardees)
Jason V. Davis - University of Texas at Austin, USA
Brian Kulis - University of Texas at Austin, USA
Prateek Jain - University of Texas at Austin, USA
Suvrit Sra - University of Texas at Austin, USA
Inderjit S. Dhillon - University of Texas at Austin, USA

Agnostic Active Learning - not from ICML 2007 but exciting as it was discovered last year, theoretical bounds were proved this year in ICML 2007.

A Bound on the Label Complexity of Agnostic Active Learning
Steve Hanneke - Carnegie Mellon University, USA

Learning about Kernels

Stumbled on Alekh Agarwal's tech report on Kernels. A good survey on kernel methods that includes recent work on this topic.

Another place to begin would be Thomas Gartner's SIGKDD explorations survey paper.