1. 1 CS 430: Information Discovery Lecture 14 Automatic Extraction of Metadata

2. 2 Course Administration No Office Hours: Tuesday October 22. Guest Lecture: Tuesday, October 22. Carl Lagoze, Distributed information retrieval Midterm Examination: Wednesday, October 23, Upson B17, 7:30 to 9:00. A sample examination and a discussion of the answers is on the web site. The midterm and final examinations aim to reward regular attendance in class (including guest lectures) and careful reading for the discussion classes.

3. 3 Course Administration TA Office Hours: Matthew Schultz will hold office hours on Tuesdays 1:30 to 2:30 every week.

4. 4 Automatic extraction of catalog data Example: Dublin Core records for web pages Strategies Manual by trained cataloguers - high quality records, but expensive and time consuming Entirely automatic - fast, almost zero cost, but poor quality Automatic followed by human editing - cost and quality depend on the amount of editing Manual collection level record, automatic item level record - moderate quality, moderate cost

5. 5 DC-dot DC-dot is a Dublin Core metadata editor for web pages, created by Andy Powell at UKOLN http://www.ukoln.ac.uk/metadata/dcdot/ DC-dot has two parts: (a) A skeleton Dublin Core record is created automatically from clues in the web page (b) A user interface is provided for cataloguers to edit the record

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7. 7 Automatic record for CS 430 home page DC-dot applied to http://www.cs.cornell.edu/courses/cs430/2001sp/ continued on next slide

8. 8 Automatic record for CS 430 home page (continued) DC-dot applied to http://www.cs.cornell.edu/courses/cs430/2001sp/

9. 9 Observations on DC-dot applied to CS430 home page DC.Title is a copy of the html field DC.Publisher is the owner of the IP address where the page was stored DC.Subject is a list of headings and noun phrases presented for editing DC.Date is taken from the Last-Modified field in the http header DC.Type and DC.Format are taken from the MIME type of the http response DC.Identifier was supplied by the user as input

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11. 11 DC-dot applied to http://www.georgewbush.com/ continued on next slide Automatic record for George W. Bush home page

12. 12 DC-dot applied to http://www.georgewbush.com/ Automatic record for George W. Bush home page (continued)

13. 13 Observations on DC-dot applied to George W. Bush home page The home page has several meta tags: [The page has no html ] <META NAME="KEYWORDS" CONTENT="George W. Bush, Bush, George Bush, President, republican, 2000 election and more

14. 14 Collection-level metadata Several of the most difficult fields to extract automatically are the same across all pages in a web site. Therefore create a collection record manually and combine it with automatic extraction of other fields at item level. For the CS 430 home page, collection-level metadata: See: Jenkins and Inman

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16. 16 Metadata extracted automatically by DC-dot D.C. Field Qualifier Content title Digital Libraries and the Problem of Purpose subject not included in this slide publisher Corporation for National Research Initiatives date W3CDTF 2000-05-11 type DCMIType Text format text/html format 27718 bytes identifier http://www.dlib.org/dlib/january00/01levy.html

17. 17 Collection-level record D.C. Field Qualifier Content publisher Corporation for National Research Initiatives type article type resource work relation rel-type InSerial relation serial-name D-Lib Magazine relation issn 1082-9873 language English rights Permission is hereby given for the material in D-Lib Magazine to be used for...

18. 18 Combined item-level record (DC-dot plus collection-level) D.C. Field Qualifier Content title Digital Libraries and the Problem of Purpose publisher (*) Corporation for National Research Initiatives date W3CDTF 2000-05-11 type (*) article type resource (*) work type DCMIType Text format text/html format 27718 bytes (*) indicates collection-level metadata continued on next slide

19. 19 Combined item-level record (DC-dot plus collection-level) D.C. Field Qualifier Content relation rel-type (*) InSerial relation serial-name (*) D-Lib Magazine relation issn (*) 1082-9873 language (*) English rights (*) Permission is hereby given for the material in D-Lib Magazine to be used for... identifier http://www.dlib.org/dlib/january00/01levy.html (*) indicates collection-level metadata

20. 20 Manually created record D.C. Field Qualifier Content title Digital Libraries and the Problem of Purpose creator (+) David M. Levy publisher Corporation for National Research Initiatives date publication January 2000 type article type resource work (+) entry that is not in the automatically generated records continued on next slide

21. 21 Manually created record D.C. Field Qualifier Content relation rel-type InSerial relation serial-name D-Lib Magazine relation issn 1082-9873 relation volume (+) 6 relation issue (+) 1 identifier DOI (+) 10.1045/january2000-levy identifier URL http://www.dlib.org/dlib/january00/01levy.html language English rights (+) Copyright (c) David M. Levy (+) entry that is not in the automatically generated records

22. 22 Collection-level metadata Compare: (a) Metadata extracted automatically by DC-dot (b) Collection-level record (c) Combined item-level record (DC-dot plus collection-level) (d) Manual record For web pages information retrieval works better by automatic indexing, rather than automatic extraction of metadata followed by indexing of metadata. However, we will see later an effective example of automated extraction of metadata from video sequences (Informedia).