LIBR 557 Advanced Information Retrieval

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Dialog

• What doesnt kill us
• makes us stronger

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Objective and Outline

• Objective to get to grips with the Dialog beast
  
• What is Dialog why study it?
• Dialog structure
• Dialog refresher
• Dialogs basic and additional indexes
• Dialog assignment

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1. What is Dialog and why study it?

• What is Dialog and why look at it?
• A database aggregator
• A data supermarket
• The biggest and the baddest
• Supports a comprehensive and complex range of
  traditional search tools
• Comprehensive help documentation

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2. Dialog Structure

• Aggregator
• Database
• File
• Journal or other publication
• Record
• Field

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Dialog Components

• Dialog interfaces
• Bluesheets
• Documentation help

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Dialog Interfaces

• Dialog Classic
• www.dialogclassic.com
• Dialog Web
• www.dialogweb.com
• Dialog Select
• www.dialogselect.com

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Dialog Bluesheets

• Written guides for every Dialog file
• http//library.dialog.com/bluesheets/
• Describe
• database contents
• structure of database
• searchable fields
• other special features

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Dialog Help Documentation

• Dialog Pocket Guide
• Successful Searching on Dialog
• GEP Lab Workbook

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3. Dialog Refresher

• Im looking for population data about Bellingham.
  How do I?
• Go to Population Demographics database?
• Search for Bellingham?
• Search for zip codes 98295 or 98281?
• Display the results for this latest search?
• See my searches so far?
• Search for everything in Bellingham except zip
  code 98295 or 98281?
• Log off?

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4. Basic Additional Indexes

• Fields in Dialog are either part of the basic
  index or the additional indexes
• Bluesheets tell you which fields are in the basic
  additional indexes

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Dialog Structure Basic Index

• Fields vary, but are usually subject-related
• Eg title, descriptor, identifier, abstract
• Basic index fields searched as default
• Can limit search to particular fields by using
  suffixes
• libraries/ti
• public libraries/de

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Basic Index Sample Searches

• Im looking for information in Library Literature
  and Information Science
• Articles on Google in the basic index
• Articles with the word Google in the descriptor
  field
• Articles with the phrase Internet search engines
  in the descriptor field

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Dialog Structure Additional Indexes

• Wide range of fields. In bibliographic databases,
  eg author, journal title
• Some databases have up to 100 additional indexes
• Not searched as a default
• Must specify fields with prefix
• aubasch, reva
• jnlibrary journal

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Additional Indexes Sample Searches

• Im looking for articles in Library Literature
  and Information Science
• by Ann Curry
• by Judi Saltman

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Word Phrase Indexing in Dialog

• A word in Dialog is a set of alphabetical or
  numeric characters surrounded by either
  punctuation or a space
• A phrase in Dialog is an entire entry in a
  field
• British General Electric Co.
• Basch, Reva
• Basch, R.

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Word Phrase Indexing in Dialog

• The basic index is usually word-indexed
• Additional indexes are usually phrase-indexed
• Descriptors and Identifiers are in the basic
  index. They are usually word-indexed and
  phrase-indexed
• teaching skills/de
• teaching(w)skills/de

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Words Phrases Sample Searches

• Im looking for information in Library Literature
  Information Science
• Harry Potter in the basic index
• Harry Potter books in the basic index
• Harry Potter books in the descriptor field
• Harry Potter in the title field
• School Libraries in the journal name field
• School Libraries in the source info. field

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Punctuation in Dialog

• A word is a set of characters surrounded by a
  space or punctuation.
• Alzheimers disease
• Alzheimer s disease
• In a phrase-indexed field, punctuation forms part
  of the phrase string and must be entered exactly
• Alzheimers disease
• Alzheimer disease

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Punctuation Sample Searches

• Im looking for information in Library Literature
  Information Science
• e-mail in the title field
• articles in the journal AB Bookmans Weekly
• using the Source Information index, articles from
  AB Bookmans Weekly

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What Next?

• Next two weeks
• Traditional information retrieval models
• How information is organized
• Search strategies tactics
• Database Trends
• More Dialog
• March 1 class
• Michele Pye Mark Jordan