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Ta Nha Linh 1TIM13 March 2009 Harvesting useful information on researchers' home pages Ta Nha Linh Supervisor: Asst. Prof. Min-Yen Kan
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Ta Nha Linh 2TIM13 March 2009 Motivation Databases dedicated to scientific publications: CiteSeer, Google Scholar, ACM Portal, SpringerLink How about the authors of those publications? Publication-centric.
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Ta Nha Linh 3TIM13 March 2009 Motivation Researcher-centric database? – Singapore Researchers Database: researchers to sign up and input, restricted conditions, in Singapore only – Resilience Alliance Reseachers Database: manual submission by researchers, in ecological and social sciences – Some other similar databases: manual update, specific to certain organization
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Ta Nha Linh 4TIM13 March 2009 Goal: Automated system to build researchers database, for multiple disciplines Where to get the information? Their home pages. – Basic information – Contact information – Educational history – Publications
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Ta Nha Linh 5TIM13 March 2009 Challenges Different layouts – Templates – Personal pages Different content – Pages introducing researchers – CV-like – Personal pages Different content structures – Tables / lists – Natural language text
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Ta Nha Linh 6TIM13 March 2009
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Ta Nha Linh 7TIM13 March 2009
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Ta Nha Linh 8TIM13 March 2009
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Ta Nha Linh 9TIM13 March 2009 Challenges Different data presentations hangli at microsoft dot com cs.duke.edu, junyang ASJMZheng@ntu.edu.sg erafalin(at)cs.tufts.edu Natalio.Krasnogor -replace all this by at symbol- nottingham.ac.uk wmt then the at-sign then uci dot edu
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Ta Nha Linh 10TIM13 March 2009 System Architecture Fields Identification (Tagging Core) Home page Identification Post Processing
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Ta Nha Linh 11TIM13 March 2009 Fields Identification - Purpose To identify data in the page contents to corresponding fields in a pre-defined set of desired information. Current set includes: Name – Position – Affiliation Address – Phone – Fax - Email BS year – BS major – BS university MS year – MS major – MS university PhD year – PhD major – PhD university Research Interest – Publications
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Ta Nha Linh 12TIM13 March 2009 Fields Identification- Related works Tang et al (2007), (2008) – ArnetMiner – Prepocessing: tokenize text into 5 categories – Tagging of tokens by using Conditional Random Field (CRF) – F1 = 83.37% (~1,000 researchers) – Set of features used: + Content features (word, morphological, image features) + Pattern features (positive word, special token, reseacher name features) + Term features (term, dictionary features)
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Ta Nha Linh 13TIM13 March 2009 Fields Identification- Related works Tang et al (2007), (2008) – ArnetMiner – Has researcher’s name as input. This is an important information to be made used of when parse other fields. Different from TIM. – Based only on text of the page. Stylistic information can be of use.
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Ta Nha Linh 14TIM13 March 2009 Fields Identification- Related works Cai et al (2003) – VIsion-based Page Segmentation (VIPS) algorithm to produce visual-based content structure of a web page – Make use of DOM tree and visual cues on web pages – May help in narrowing down relevant sections – Drawback: need a browser to get the visual information
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Ta Nha Linh 15TIM13 March 2009 Fields Identification- Related works Lee (2004) PARCELS Stylistic Engine – Made use of some heuristics proposed by Cai et al (2003) – Parse the DOM tree for text-only and stylistic properties – Text-only data passed to another engine for further process – Stylistic data is stored in vector for machine learning, to classify sections with a set of domain-specific tags. – The domain used was the news domain
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Ta Nha Linh 16TIM13 March 2009 Fields Identification- Method Input: a researcher home page CRF is employed as the automated learning model Features used – Global features – Lexicon features – Context features – Dictionaries features – Stylistic features
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Ta Nha Linh 17TIM13 March 2009 Fields Identification- Method Global features: apply for current token – Morphological features – Initials – Number – Punctuation Lexicon features: apply for current token – Positive words for certain annotation fields: Position, Affiliation, Address, Phone, Fax, Email
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Ta Nha Linh 18TIM13 March 2009 Fields Identification- Method Context features: apply for whole line – Name context – Address context – Phone context: 'phone', 'tel', 'mobile' – Fax context: 'fax', 'facsimile' – Email context: 'email', 'e-mail' – Bachelor (BS) context: appearance of 'B.S' or 'BS' or 'Bachelor' – Master (MS) context: appearance of 'M.S' or 'MS' or 'Master' – Ph.D (PhD) context: appearance of 'Ph.D' or 'Doctorate' or 'Doctor(ate) of Philosophy' – Research-interest context: multiple line property – Publication context: multiple line property – Degree: help to correctly differentiate BS/MS/PhD info when they are presenting in prose style / on the same line.
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Ta Nha Linh 19TIM13 March 2009 Fields Identification- Method Dictionaries – Parscit dictionary: detect male names, female names, popular last names, month names, place names, publisher names, each is a single feature – Major dictionary: to help in identifying researchers' major in their educational history, may also help in Research Interests – Research dictionary: classified into high/mid/low confidence. – Universities dictionary: of names of most of universities, according to Open Directory
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Ta Nha Linh 20TIM13 March 2009 Fields Identification- Method Stylistic features – List feature – Table features – Section feature: based on html tags like,,, header tags, list elements, table
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Ta Nha Linh 21TIM13 March 2009 Fields Identification - Performance Data set of 40 home pages, cross validation processed 29271 tokens with 29271 phrases; found: 29271 phrases; correct: 23444.accuracy: 80.09%; precision: 80.09%; recall: 80.09%; FB1: 80.09 address: precision: 78.90%; recall: 74.57%; FB1: 76.67 327 affiliation: precision: 30.27%; recall: 59.47%; FB1: 40.12 1110 bs-major: precision: 88.89%; recall: 78.05%; FB1: 83.12 36 bs-uni: precision: 68.67%; recall: 57.00%; FB1: 62.30 83 bs-year: precision: 90.00%; recall: 72.00%; FB1: 80.00 20 email: precision: 79.31%; recall: 70.77%; FB1: 74.80 58 fax: precision: 47.73%; recall: 72.41%; FB1: 57.53 88 misc: precision: 85.23%; recall: 92.35%; FB1: 88.65 22888 ms-major: precision: 71.43%; recall: 32.26%; FB1: 44.44 14 ms-uni: precision: 52.94%; recall: 52.94%; FB1: 52.94 85 ms-year: precision: 77.78%; recall: 56.00%; FB1: 65.12 18 name: precision: 75.66%; recall: 51.34%; FB1: 61.17 152 phd-major: precision: 83.33%; recall: 73.17%; FB1: 77.92 36 phd-uni: precision: 74.56%; recall: 72.03%; FB1: 73.28 114 phd-year: precision: 100.00%; recall: 74.07%; FB1: 85.11 20 phone: precision: 53.38%; recall: 89.25%; FB1: 66.80 311 position: precision: 79.46%; recall: 64.49%; FB1: 71.20 112 publications: precision: 71.05%; recall: 43.27%; FB1: 53.79 3240 research-interest: precision: 48.48%; recall: 36.04%; FB1: 41.34 559
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Ta Nha Linh 22TIM13 March 2009 Fields Identification - Discussion Data fields to be annotated similar to those from ArnetMiner. – Extra: Name, Research Areas, Publications – Missing: Image Stylistic feature used is minimal
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Ta Nha Linh 23TIM13 March 2009 Fields Identification - Discussion F1 value is slightly lower than that of ArnetMiner’s – ArnetMiner has the researcher name as input, and uses features referring to researcher name to identify other fields. TIM has absolutely no prior knowledge about the page to be parsed. – Identifying ‘Research Interest’ and ‘Publications’ is the most challenging. Not always presented. If presented, in various styles
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Ta Nha Linh 24TIM13 March 2009 Home page Identification - Purpose Add-on component To complete automation of the system: finding home pages to input to the Fields Identification component.
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Ta Nha Linh 25TIM13 March 2009 Home page Identification – Related works Ahoy! – Input: Researcher name and institution name (optional) – Use MetaCrawler as a 'reference source', cross filter by email database – Heuristic-based filter: based entirely on reference's tile, URL, short textual extract (if supplied by the search engine) – Ranking: based on 1/ person name match, 2/ institution URL match, 3/ page appears to be a homepage – URL Pattern Extraction and Generation: extract and learn the pattern if a success, else generate URL from database of URL patterns
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Ta Nha Linh 26TIM13 March 2009 Home page Identification – Related works Ahoy! – Dynamic search, high performance reported, URL patterns usage a good feature – Does not serve the same purpose as my Home page Identification: should not take researcher name as input. – Definition of ‘home page’ is not the same. Ahoy! classifies based on URL patterns, TIM classified based on page contents.
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Ta Nha Linh 27TIM13 March 2009 Home page Identification – Method Collect a list of Universities domains Use Yahoo! BOSS to search for professors in the institutions For each valid web page, fetch the page, scan for words indicating ‘phone’, ‘mail’ and ‘professor’. Count the number of appearance. – #phone < 3 && #mail < 2 && #professor < 5 Home page Home pages will be passed to Fields Identification component.
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Ta Nha Linh 28TIM13 March 2009 Home page Identification – Discussion Query to Yahoo! BOSS is not optimal. But this covers the majority Drawback: result set from Yahoo! BOSS may get duplicate pages, or sub-pages of a researcher’s home page Treated as 2 different records. – Need high confidence in overall system performance. But researcher names are not unique. – Best if can eliminate duplication by analyzing URLs. But domain hierachies differ within department, between departments, and between institutions.
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Ta Nha Linh 29TIM13 March 2009 Post-processing - Purpose Input: CRF++ output file from Fields Identification. Group neighboring tokens identified with the same annotation tag Deduplication Store into database
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Ta Nha Linh 30TIM13 March 2009 Contribution Produced an automated system for fetching researchers’ information from the world wide web. Introduced a number of features for Fields Identification machine learning.
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Ta Nha Linh 31TIM13 March 2009 Future improvements Fields Identification – Introduce more features, especially stylistic features – Strengthen features targeting Name, Research Interest and Publications tags – Cater for the tag – Be able to handle pages using HTML frames – Be able to follow links on the page if necessary Home page Identification – Improve heuristics Post-processing – Be able to refine output from Fields Identification A new component to facilitate front end for user to query the database
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Ta Nha Linh 32TIM13 March 2009 THANK YOU! Question?
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