Principles of Searching © Tefko Saracevic1 La búsqueda en la web & la web invisible Buscando lo...

© Tefko Saracevic 1Principles of Searching

La búsqueda en la La búsqueda en la web & la web invisibleweb & la web invisible

Buscando lo difícil de buscar


Definiciones de diccionario

World wide web :Archivos conectados a través de Internet

Enorme conjunto de documentos y otros archivos enlazados localizados en ordenadores conectados a través de Internet y utilizados para acceder, manipular, y descargar datos y programas

Invisible - Definición de diccionario:

Que no puede ser visto

Web Invisible– No está en el diccionario


What is “Invisible web?” Materiales que no incluyen, o no quieren incluir, los

buscadores generales en su colección de páginas web (índices) Inencontrables a través de los buscadores generales

Contiene una enorme cantidad de recursos de información En buena medida de mayor calidad y autoridad que la de la web

visible La calidad es su principal característica

Especializada Parte de ella fluye, o está en streaming o en tiempo real

“No puedes bañarte dos veces en el mismo río” Parte de ella gratuita

Mucho más extensa que la Web visible


en otras palabras…Hay mucho más en la web que

o


¿Porqué los buscadores no cubren todo?

Tamaño: La web es enorme, no pueden abarcarlo todo Factores Económicos: Los costes asociados son altos

Los buscadores viven de la publicidad Cierto número de buscadores ofrecen resultados de pago

FactoresTécnicos: Capacidad limitada Algunos formatos de archivo son difíciles de tratar

Spam: Eliminan lo malo pero se puede perder lo bueno Restricciones: Algunos sitios no permiten acceso a los

buscadores Estructura profunda : Algunos sitios son complejos


Cómo trabajan los buscadores?

Crawlers, spiders: buscan contenido Localizan sitios nuevos o modificados De maneras periódica, no en cada búsqueda

Ningún buscador trabaja en tiempo real (salvo Gnews) Organización de contenido: etiquetado, ordenación

Indización para búsquedas o clasificación en directorios

Bases de Datos, cachés: almacenamiento de contenidos Motor de búsqueda: en función de las demandas Interface: petición de búsqueda, visualización de resultados

Todo ello basado en algoritmos varios, habitualmente ocultos o secretos


Cobertura de los buscadores

No cubren más allá de un 20% Difícil (imposible) discernir & comparar cobertura

Buscadores nacionales Cobertura y orientación propia

Muchos buscadores especializados Cobertura propia hacia un tema de interés

Fuentes independientes de material útil Recopilaciones de recursos evaluados


Los buscadores difieren

Hay diferencias muy importantes entre los tipos de buscadores citados Necesidad de saber cómo funcionan y en qué

difieren Información sobre buscadores:

Search Engine Watch ratings, news, statistics, charts, explanations, tutorials

Search Engine Showdown “The users’ guide to web searching” - run by a librarian,

news links, ratings


Búsqueda en la web Invisible : Datos básicos

Primer paso: Saber claramente qué estás buscando. Limitar la búsqueda a recursos y herramientas

apropiadas al tipo de información que estás buscando Conocer las fuentes Saber encontrar fuentes


Fuentes especializadas -en la web invisible

1. Meta buscadores

2. Buscadores y catálogos especializados

3. Buscadores y catálogos temáticos

4. Fuentes de referencia

5. Bibliotecas

6. Bibliotecas virtuales

7. Bases de datos especialiuzadas

8. Sociedades, organizaciones

9. Libros!!!


Metabuscadores

Metabuscadores buscan en otros B. Combiando resultados

Dónde encontrar buscadores o metabuscadores:

SearchEngines.comsearch for engines by topic, geography, reference

Search Engine Guide engines categorized by topic; other engine information

Search Engine Colossus international directory of search engines by country, topic from

198 countries and 61 territories; engines in choice of languages


Sample of meta engines Some meta engines provide organized results:

Dogpile results from a number of leading search engines; gives

source, so overlap can be compared; (has also a (bad) joke of the day)

Surfwax gives statistics and text sources & linking to sources; for some

terms gives related terms to focus

Teomaresults with suggestions for narrowing; links resources

derived; originated at Rutgers

Turbo10provides results in clusters; engines searched can be edited


meta search engines (cont.)

Large directory Complete Planet

directory of over 70,000 databases & specialty engines

Results with graphical displays Vivisimo

clusters results; innovative Webbrain

results in tree structure – fun to use

Kartooresults in display by topics of query


Domain engines & catalogs

Cover general & specific subjects Open Directory Project

large edited catalog of the web – global, run by volunteers BUBL LINK

selected Internet resources covering all academic subject areas; organized by Dewey Decimal System – from UK

Profusion search in categories for resources & search engines

Resource Discovery Network – UK“UK's free national gateway to Internet resources for the

learning, teaching and research community”


domain engines …

Available in variety of domains & subjects – rich! Think Quest – Oracle Education Foundation

education resources, programs; web sites created by students

All Music Guide resource about musicians, albums, and songs

Internet Movie Database treasure trove of American and British movies

Genealogy links and surname search engineswell.. that is getting really specialized (and popular)


domain engines …

Scholarship, science Psychcrawler - Amer Psychological Association

web index for psychology Entrez PubMed – Nat Library of Medicine

biomedical literature from MEDLINE & health journals CiteSeer - NEC Research Center

scientific literature, citations index; strong in computer science

Scholar Googlesearches for scholarly articles & resources

Infominescholarly internet research collections


Reference services

Reference services - several models Q&A, directories, email answers etc.

Ask Jeeves! most popular, commercial

Information Please almanac type questions

RefDeskaccess to a number of reference tools

Wikipediaweb encyclopedia in many languages


reference …

• Digital reference - new service area for libraries QuestionPoint L of Congress & OCLC

project for a global reference network Virtual Reference Desk – L of Congress

large compilation of web reference sites LiveRef - maintained at Iowa State U

a registry of real time digital reference services


Libraries as web sources

Academic, national libraries providing open collections & services; models vary Rutgers libraries - big long term effort University of California, Berkeley

a most elaborate effort together with Sun Corporation

LibWeb U California, Berkeley

“lists currently over 7200pages from libraries in over 125 countries”

Bibliothèque Nationale de France includes virtual exhibitions, among others


Virtual libraries on the Web

Libraries emerging only on the Web Virtual Library –

Switzerland, US, UK & other countries – ‘oldest virtual library on the Web’

Internet Public Library U of Michigan also a long term effort

Librarians Index of the Internet very popular and comprehensive

Digital librarian

“a librarian's choice of the best of the Web “ – compiled and annotated by a librarian


virtual libraries …

Academic Info Digital Library many links to digital collections & resources in various subjects

Gabriel Gateway to European National Libraries

Museum of online museums a delight

Stanford Encyclopedia of Philosophy

a comprehensive encyclopedia and libraryThe historical New York Times Project

universal library – ongoing digitization


Subjects resources Many subject specific sites

rich & often unique coverage & services different approaches & requirements

Examples in health related domains: WebMDHealth

news, medical information Rxlist

The Internet Drug Index Mayo Clinic HealthOasis

health advice

Kidshealthsites for parents, kids, teens


Subject resources …

Scholarship, humanities, government KIRKE - Katalog der Internetressourcen für die

Klassische Philologie aus Erlangen German; a variety of resources for classics

Perseus Digital Library Tufts University covers antiquity to renaissance; one of the best subject

sites on the web; affected the whole field Sch of Slavonic & East European Studies, University

College London includes country resources, e.g. Croatia U Mich Document Center official documents from all over the world


Subject resources … Growing number of resources in arts, museums

MuseumStuff.com

“We have 1000's of museums, zoos, historical societies and related organizations in our database”

The State Hermitage Museum

One of the greatest museums in the world, and one of the best museum site – developed with IBM help

National Museum of Science and Technology Leonardo da VinciGuess where those pictures came from. A delight!


subject resources …

DiotimaMaterials for study of women and gender in the Ancient World

Moving Images Collections“MIC documents moving image collections around the world.”

Part particularly oriented toward science educators. Now at Library of Congress, but developed at Rutgers.

And, of course …

Snoopy

The Official Peanuts Website


Societies, organizations Many societies, agencies developed their sites

great many rich sources for searching & resources differences in requirements, depth, richness Assoc. for Computing Machinery

Digital Library; subscription or registration or through RUL US State Department

about the U.S & other countries

FirstGovthe US government official web portal

Ocean Planet NASApresentation of earth & its vast oceans

ArXiv Cornell U, National Science Foundatione-print service in the fields of physics, mathematics, non-linear

science, computer science, and quantitative biology


Archiving, books on the web Internet Archive – a large undertaking

includes web archive & lots more publicly available & free 10 billion web pages archived from 1996 to a few months ago Wayback Machine – search to look at old versions of web

pages Books on the web

Million Book Project digitizing books and providing free access

International Children’s Digital Libraryonline children books

Digital books Index“links to more than 105,000 title records from more than 1800

commercial and non-commercial publishers, universities, and various private sites”


Language barriers on the Web

English still the major language but declining, now slightly over 50%

Multilingual retrieval search engines Euroseek

searches in a number of languages All the Web

results in 45 languages


Web news; keeping up

What is going on on the Web? Some major sources of news and evaluations: Free Pint

newsletter, articles, links; nice & sometimes quirky Internet Resources Newsletter

UK based; monthly newsletter for “academics, students, engineers, scientists and social scientists”

ResearchBuzz daily updates; many aspects; “Collection of items on search

engines, online databases, and other information resources” About.com Web Search

tools, Web Search Forum


keeping up …

Information Todaytrade & professional monthly newspaper & web site; industry

news; searcher columns; general analyses of trends

Keeping up through blogosphere: Resource Shelf

bloger about internet (and some other stuff) with archive; it has really good and really bad exchanges & threads

New York Times blogrunner - The annotated NYT blog tracking of NYT articles, topics, authors; thread into

discussion of many other weblogs; includes net & web topics


Finding links & listings – back to good old books with a new twist

Number of books on web searching have also sites with links in the book, updates, news Extreme Searcher Randolph Hock

update of a popular book; links by chapter topics

The web library Nicholas G. Tomaiuolospotlights free resources, links by chapter and new topics –

done by a librarian

The invisible web Chris Sherman & Gary Priceoriginal book on the topic, links organized by subject

p.s. most, but not all, of the sites in this lecture can be found on those sites – and much, much more


Evaluations, ratings Evaluating web sites: a prime responsibility of

searchers & all information professionals Many sources evaluate web sites:

The Scout Report – librarians’ BIBLE! Annotations. Comprehensive.

Medical Library Association ten most useful sites for consumer health

MLA user guide for finding & evaluating health information on the web

Web 100 commercial, user ranking & evaluation of web sites Evaluating web pages UC Berkeley

tutorial and guide


Needed for Web searching Knowledge & competencies on

variety of web sources & their organization search engines web search strategies search dynamics, feedback

Keeping up & up & up Why? many reasons, such as:

constant updates, changes, innovations many domain/subject specific fluidity very high


Needed for web searching by professionals

Knowledge of SOURCES in area of interest search engines not enough

not too helpful in finding these other sources; structure hard to discern

find & use specialized sources Evaluation of sources

a key professional skill! application of standard criteria & web criteria:

authority; accuracy; currency (timeliness); objectivity; coverage, persistence, usability


Needed competencies …

Knowledge of users & use Knowledge of searching Use of technology Adaptability, flexibility Integration with other resources Teaching others Constant learning & update

again: keeping up, keeping up, keeping up and again: keeping up, keeping up, keeping up


information

WWW

But now really: How to do it?


Imagesfrom the invisible web


images …


and of course…


P.S. a nice site

Poem by Emily Dickenson:

In a library

Who will write a poem:

In a digital library?


P.S. a few weird sites…

SelectSmart.com all kinds of quizzes for you

James Dean official web site Deaducated

Dead Librarians’ Society Livejournal

blogs & authoring tools; and many pathetic entries


Sources About.com Web Search http://websearch.about.com Academic Info Digital Library http://www.academicinfo.net/digital.html All the Web http://www.alltheweb.com/ Ask Jeeves! http://www.ask.com/ Assoc. for Computing Machinery http://www.acm.org/ Bibliothèque Nationale de France http://www.bnf.fr/ BUBL LINK http://bubl.ac.uk/link/ CDNET Search.com http://www.search.com/ CiteSeer http://citeseer.nj.nec.com/ CompletePlanet http://completeplanet.com Deaducated http://www.geocities.com/deadlibrarians/ Digital book index http://www.digitalbookindex.org/about.htm Digital librarian http://www.digital-librarian.com/ Diotima http://turbo10.com/ Dogpile http://www.dogpile.com/ Entrez PubMed http://www.ncbi.nlm.nih.gov/PubMed/ Extreme Searcher http://www.extremesearcher.com/ Free Pint http://www.freepint.com/ Gabriel http://www.kb.nl/gabriel/ Genealogy http://darcisplace.com/darci/search.htm


sources … Hermitage http://www.hermitagemuseum.org/html_En/index.html Information Please http://www.infoplease.com/ International Children’s Digital Library http://www.icdlbooks.org/ Internet Archive http://www.archive.org/ Internet Public Library, Michigan http://www.ipl.org/ Internet Resources Newsletter. http://www.hw.ac.uk/libwww/irn/ James Dean http://www.jamesdean.com/ Kartoo http://www.kartoo.com/ KIRKE http://www.phil.uni-erlangen.de/~p2latein/ressourc/ressourc.html Leonardo da Vinci Museum http://www.museoscienza.org/english/ Librarians Index to the Internet http://lii.org/ Live Journal http://www.livejournal.com/ LiveRef http://www.public.iastate.edu/~CYBERSTACKS/LiveRef.htm Mayo Clinic http://www.mayohealth.org/ Medical Library Assoc. ten top sites http://www.mlanet.org/resources/medspeak/topten.html Medical Library Assoc. user guide for health inf.

http://www.mlanet.org/resources/userguide.html Medscape http://www.medscape.com/


sources … Million Book Project http://www.archive.org/texts/collection.php?collection=millionbooks Museum of online museums. http://www.coudal.com/moom.php MuseumStuff http://www.museumstuff.com/ NYT blogrunner http://nytimes.blogrunner.com/ NYT historical project http://www.nyt.ulib.org/ OCLC Web Characterization Project http://wcp.oclc.org/ Open Directory Project http://dmoz.org Perseus Digital Library http://www.perseus.tufts.edu/ Profusion http://www.profusion.com/ Psychcrawler http://www.psychcrawler.com/ QuestionPoint http://www.questionpoint.org/ ResearchBuzz. http://www.researchbuzz.com/index.shtml Resource Shelf http://resourceshelf.blogspot.com/ Rutgers Libraries http://www.libraries.rutgers.edu/ RxList http://www.rxlist.com/ Sch of East Eur & Slavonic Studies http://www.ssees.ac.uk/dirctory.htm Search Engine Colossus http://www.searchenginecolossus.com/ Search Engine Guide http://www.searchengineguide.com/ Search Engine Showdown http://searchengineshowdown.com/


sources … Search Engine Watch http://searchenginewatch.com/ Select Smart.com http://www.selectsmart.com/home.html Snoopy http://www.snoopy.com/ Stanford Encyclopedia of Philosophy http://plato.stanford.edu// Surfwax http://www.surfwax.com/ Teoma http://teoma.com/ The invisible Web http://www.invisible-web.net/ The Scout Report. http://scout.cs.wisc.edu/ The Web Library http://www.ccsu.edu/library/tomaiuolon/theweblibrary.htm Think Quest http://www.thinkquest.org/ Turbo10 http://turbo10.com/ U California Berkeley http://sunsite.berkeley.edu/ U Mich Documents Center http://www.lib.umich.edu/govdocs/ US State department http://www.state.gov/ Virtual Library http://vlib.org Virtual Reference Desk http://www.loc.gov/rr/askalib/virtualref.html Vivisimo http://vivisimo.com Web 100 http://www.web100.com Webbrain http://www.webbrain.com/html/default_win.html WebMD http://my.webmd.com/webmd_today/home/default Wikipedia http://www.wikipedia.org/

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