Transcript of 1 Workshop: Finding information through the Internet and the WWW in 2003: “You mean Google?”...
- Slide 1
- 1 Workshop: Finding information through the Internet and the
WWW in 2003: You mean Google? Paul Nieuwenhuysen Vrije Universiteit
Brussel Information and Library Science, University of Antwerp
Belgium Presented at the international conference Libraries in the
Digital Age - LIDA 2003 at the Inter-university Centre, in
Dubrovnik, Croatia, May 2003
- Slide 2
- 2 These slides are available from
http://www.vub.ac.be/BIBLIO/nieuwenhuysen/presentations/ (note:
BIBLIO and not biblio)
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- 3 Contents / summary of this presentation and workshop A
systematic overview of information sources and services that are
accessible through the Internet, such as general WWW directories
and search engines, and more specialized systems to find books
journal articles newsgroup messages images/pictures + Evaluation of
information sources
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- 4 Sunset near the palace in Dubrovnik 25 May 2003
- Slide 5
- 5 -Interruptions -Questions -Remarks -Discussions are all
welcome! This is a workshop; so everyone should work!
- Slide 6
- 6 Online access information sources and services
Introduction
- Slide 7
- 7 Growing importance of computer network information resources
Networked information resources are growing at a high rate, not
only in volume but also in importance. There are many sources there
which are vital to research and many others which are useful
generally. To keep abreast of their field, most academics and
researchers will find an increasing need to use the network for
fast and efficient communication and for access to information. If
they dont, they are likely to be left behind, because most of their
colleagues in institutions around the world will be doing just
that.
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- 8 Online access to information: avoid network traffic jams To
access from Europe online information sources in the US, work when
lines are not saturated. (better in the morning than in the
afternoon)
- Slide 9
- 9 Internet based information sources: problems / difficulties
(Part 1) Redundancy and overlap: On the one hand, there is too much
information on some topics; in other words, the redundancy and
overlap are high in many cases. Too few information sources: On the
other hand, there are too few information sources on some
topics.
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- 10 Internet based information sources: problems / difficulties
(Part 2) No order is imposed on most sources. Quality checks /
quality controls are not performed. Related to this: it is not
required to register new information offered. Is the information
that you find real, honest, authentic?
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- 11 Internet based information sources: problems / difficulties
(Part 3) Change is the only constant: Information sources are
constantly changing, growing, but sometimes disappearing.
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- 12 Internet based information sources: problems / difficulties
(Part 4) Scattering: There is no single simple but powerful system
to find relevant information through the Internet. In other words:
integration / aggregation is still far from perfect.
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- 13 Internet based information sources: problems / difficulties
(Part 5) Slow: The Internet is in many places and for many
applications not yet fast enough.
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- 14 Internet based information sources: problems / difficulties
(Part 6) In conclusion: Surfing, using the Internet, the WWW, can
be a time sink instead of a productive activity.
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- 15 Internet based information sources: how many? how much
information? In 2001: More than 10 terabyte (= 10 000 gigabyte) of
text data In 2002: More than 2000 million (= 2 billion) unique URLs
in the total Internet
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- 16 Increasing number of online public access databases Source:
Gale Directory of Databases, 1997.
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- 17 Online access information sources and services Types of
online access information systems
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- 18 Primary versus secondary computer sources / systems /
services Primary sources /systems /services directly useful
Secondary sources /systems /services helping to access / use the
primary services travel agencies, navigation services,...
- Slide 19
- 19 Types of online access information systems: free versus fee
A lot of the information on the Internet is available free of
charge, but another part is only accessible when a fee is paid to
the producer and / or the distributor. Some organisations pay these
fees for some sources and then organise access, so that the members
of the organisation can retrieve and exploit the information as if
it is free of charge.
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- 20 Types of online access information systems: free versus fee
Public access information sources free of charge Fee-based online
information services (NOT free of charge)
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- 21 Types of online access information systems: free for members
only Public access information sources free of charge Fee-based
online information services (NOT free of charge) Fee-based online
information services, made accessible free of charge by an
institute to its members
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- 22 Types of online access information sources by file format
For instance: TXT (ASCII) DOC HTM, HTML, SHTML, PDF PCX TIF, TIFF
GIF JPG PNG AVI MPG ASF
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- 23 Online access information sources and services Dictionaries
and encyclopaedias accessible through the WWW
- Slide 24
- 24 Dictionaries and encyclopedias through the WWW: introduction
Dictionaries and encyclopedias are the first choice among many
types of information sources, when we do not need detailed
information on a common topic when we want to prepare a more
detailed search on an unfamiliar topic, by searching for the right
spelling, synonyms, context, Some dictionaries and encyclopedias
are available through the WWW free of charge.
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- 25 Dictionaries accessible through Internet and the WWW:
example The American Heritage Dictionary of the English Language
Over 200,000 entries, 70,000 audio word pronunciations, 900
full-page color illustrations Available free of charge from
http://education.yahoo.com/reference/dictionary/
http://education.yahoo.com/reference/dictionary/ Example
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- 26 Dictionaries accessible through Internet and the WWW:
compilation A compilation/collection of dictionaries can be
searched simultaneously and free of charge: http://www.onelook.com/
http://www.onelook.com/ Example
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- 27 Encyclopedias accessible through Internet and the WWW:
examples Encarta Concise Free Encyclopedia
http://encarta.msn.com/http://encarta.msn.com/ Available in English
and in some other languages Example
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- 28 Encyclopedias accessible through Internet and the WWW:
examples Encyclopdia Britannica only a small part is available free
of charge + links to selected WWW sites
http://www.britannica.com/http://www.britannica.com/ Encyclopdia
Britannica Concise
http://education.yahoo.com/reference/encyclopedia/http://education.yahoo.com/reference/encyclopedia/
Example
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- 29 Encyclopedias accessible through Internet and the WWW:
examples The Canadian Encyclopedia (in English and in French):
http://thecanadianencyclopedia.com/http://thecanadianencyclopedia.com/
Example
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- 30 Encyclopedias accessible through Internet and the WWW:
examples Several encyclopedias and dictionaries have been
integrated and are searchable simultaneously and free of charge
through http://xrefer.com/ http://xrefer.com/ Example
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- 31 Encyclopedias accessible through Internet and the WWW:
overviews A list / overview of encyclopedia on the Internet:
http://www.internetoracle.com/encyclop.htm
http://www.internetoracle.com/encyclop.htm Other lists of
encyclopedia on Internet can be found as a part of more general
directories of Internet-based information sources. Example
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- 32 Online access information sources and services Internet
directories and indexes
- Slide 33
- 33 Internet: meta-information about Internet information
sources in printed manuals and guides: - it is not always possible
to get a copy fast - it costs money to get a copy - they are soon
out of date offered on the WWW!: + directly available when we want
to use the Internet + many systems are accessible free of charge +
most systems are regularly updated (intelligent agent software on
client PC)
- Slide 34
- 34 Internet: subject-oriented meta- information offered via WWW
Information about information sources: in the form of subject
guides = texts with references subject hypertext directories =
subject guides key word indexes, generated automatically, for
searching collections of links or forms to the above
(multi-threaded search systems)
- Slide 35
- 35 Internet global subject directories: introduction They are
virtual libraries with open shelves, for browsing. They are
manually generated, man-made by many people. They can be browsed
following a tree structure or a more complicated variation. The
most famous of these systems belong to the most popular and most
visited sites on the WWW: e.g. Yahoo!
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- 36 Internet global subject directories: structure The structure
corresponds to a classification that is in most cases specific for
the particular overview. In other words: the well-known and
classical universal classification systems are not used in most
Internet directories.
- Slide 37
- 37 Internet global subject directories: limitations They cover
only a small number of selected WWW sites, in comparison with the
total number of sites that are accessible. They are suitable mainly
for broad searches that can be difficult to formulate in words, but
NOT for more specific searches that require combinations of several
concepts.
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- 38 Internet global subject directories: searching directories
with a query Many of the Internet directories include an index to
search their contents with a query. However, then the assisting
classification structure is not well exploited and the user should
be aware of the problems and difficulties of information retrieval
with natural language queries. Furthermore, the possibility to use
the system in this way may be confusing, as these directories are
not real full- text Internet indexes, like those provided by other
search tools.
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- 39 Internet global subject directories: Yahoo! A hypertext
global subject directory can be found at
http://www.yahoo.com/http://www.yahoo.com/ and at many other sites,
including http://www.yahoo.co.uk/ http://www.yahoo.co.uk/ Entries
are NOT rated. Accessible free of charge. Example
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- 40 Internet global subject directories: Yahoo! links in
pediatrics Health > Medicine > Pediatrics: International
Pediatric Chat - for professionals to share information and
education regarding children's health care.International Pediatric
Chat National Med/Peds Residents' Association - organization for
residents, practioners and medical students interested in combined
internal medicine and pediatrics.National Med/Peds Residents'
Association Neonatology Network - information and communication
platform for neonatologists and pediatricians.Neonatology Network
Pediatria OnLine - qui si parla di bambini, fra pediatri e con le
famiglie.Pediatria OnLine Pediatric Critical Care Pediatric
Database (PEDBASE) - containing descriptions of over 500 childhood
illnesses.Pediatric Database (PEDBASE) Pediatric Endocrinology
Conference - LWPES/ESPE joint meeting occuring July 6-10
2001.Pediatric Endocrinology Conference Pediatric Endoscopic Photos
- illustrating intestinal problems in children.Pediatric Endoscopic
Photos Example
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- 41 Internet global subject directories: Yahoo! for pediatrics
Health > Medicine > Pediatrics: link to a digital library
(health sciences) for young patients Example
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- 42 Internet global subject directories: Yahoo! to pediatrics
organisations Health > Medicine > Pediatrics >
Organizations: link to the American Academy of Pediatrics
Example
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- 43 Internet global subject directories: Yahoo! links to
pediatrics schools Health > Medicine > Pediatrics
>Schools, Departments, and Programs University of Rochester -
partnership between pediatric residents and community-based
agencies that serve children and their families.University of
Rochester Michigan State University@ Royal College of Paediatrics
and Child Health - responsible for training, examinations,
professional standards, and organisation of child health services
for the UK.Royal College of Paediatrics and Child Health Tohoku
University University of Alabama at Biringham - programs and
training opportunities in pediatrics. Also contains faculy
information and sub-speciatlty descriptions.University of Alabama
at Biringham Example
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- 44 Internet global subject directories: searching with a query
in Yahoo! (1) The directory of Yahoo! can not only be browsed, but
can also be searched with a query. However, in this way the
hierarchical structure is not well exploited. For the formulation
of a search query, Yahoo! can provide automatic assistance related
to spelling and word variations. For instance: After searching for
Capetown, Yahoo! Answers: Other Spellings: Try searching for cape
town instead.cape town Example
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- 45 Internet global subject directories: searching with a query
in Yahoo! (2) When such a query does not provide results, then
Yahoo! uses a much larger external Internet index (not produced by
Yahoo!) to execute a query based on textual search statements. The
chosen Internet index has varied over time. This mechanism is not
made very clear and may confuse the user. Example
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- 46 Internet global subject directories: Google directory A
hypertext global subject directory can be found at
http://directory.google.com/ http://directory.google.com/
Accessible free of charge. Very similar to the Open Directory
Project. Example
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- 47 Internet global subject directories: Open Directory Project
A hypertext global subject directory can be found at
http://www.dmoz.org/ http://www.dmoz.org/ The contents is also used
by in the Google Directory system. Accessible free of charge.
Example
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- 48 Internet global subject directories: Resource Discovery
Network A collection of hypertext subject directories that focus on
academic information sources can be found at http://www.rdn.ac.uk/
http://www.rdn.ac.uk Together these lead to more than 30 000
selected WWW sites. Accessible free of charge. Example
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- 49 Internet global subject directories: evaluation criteria -
desiderata (1) Is usage free of charge? Wide coverage? Up to date?
Frequent updates? Only few dead / broken links? Good coverage of
the sources in that part of the world in which you are interested?
Does the manager of the directory refuse to give priority to sites
that want to pay to get a prominent place in the directory?
- Slide 50
- 50 Internet global subject directories: evaluation criteria -
desiderata (2) Easy user interface? Short response times? Are
mirror sites available closer to you for faster response? Good
presentation, description of each site? Is a rating, appreciation,
review offered for each listed site? Is translation of documents
offered free of charge?
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- 51 Internet global subject directories: evaluation criteria -
desiderata (3) Good documentation and online help? Good help desk
available? High stability and reliability?
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- 52 Internet global subject directories: evaluation criteria -
desiderata (4) Are other services offered from the same site or
with the same interface? Is the subject directory integrated with
other services? Additional services can be an Internet index or a
WWW index or a gateway to such an index for searching with a query
travel guides, flight and hotel reservations, maps,... WWW-based
e-mail and e-mail address directories auctions through WWW
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- 53 Internet subject directories: non-global, more specific
systems a directory limited to sources in/of a country or region a
directory restricted to a specific subject domain (portal) a global
subject directory the complete WWW can lead to
- Slide 54
- 54 Internet subject directories focusing on a specific subject
domain (Part 1) Marine science and oceanography:
http://oceanportal.org/ =
http://ioc.unesco.org/oceanportal/http://oceanportal.org/http://ioc.unesco.org/oceanportal/
Engineering, mathematics, computing:
http://www.eevl.ac.uk/http://www.eevl.ac.uk/
http://www.ub.lu.se/eel/http://www.ub.lu.se/eel/ Civil engineering:
http://www.icivilengineer.com/http://www.icivilengineer.com/
Fishing: http://www.onefish.org/http://www.onefish.org/
Examples
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- 55 Internet subject directories focusing on a specific subject
domain (Part 2) Medicine and healthcare: general:
http://www.achoo.com/ http://www.medmatrix.org/
http://www.medscape.com/ http://www.omni.ac.uk Medicine and
healthcare: General pediatrics: http://GeneralPediatrics.com
http://www.medscape.com/pediatricshome http://www.pedinfo.com/
Examples
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- 56 Internet indexes: automated search tools Several systems
allow to search for and to locate many items (addressable
resources) in the Internet in a more systematic, direct way than by
only browsing/navigating. These systems do NOT search the contents
of computers through the real Internet in real time and completely
when a user makes a query. Searching in that way would be much too
slow due to limitations in the technology.
- Slide 57
- 57 Internet indexes: scheme of the mechanism User searching for
Internet based information Internet client hardware and software
user interface to a search engine Internet information source
Internet index search engine Internet crawler and indexing system
database of Internet files, including an index
- Slide 58
- 58 Internet indexes: description of the mechanism Each of these
search systems is based on: a database of links to pages / URLs
that can be retrieved by searching with queries through a big index
that is built machine-made on the basis of the contents, the texts,
of these pages (to build this database and to keep it up to date,
pages are continuously collected from the Internet by a robot
computer software system) a search system with a user interface in
a WWW form, to allow the user to search through that database
- Slide 59
- 59 Internet indexes: building their database Inverted file,
full text index, register of the database User Records derived from
the input and stored in the database Internet documents fed into
the database management system Indexing Retrieval
- Slide 60
- 60 Internet indexes: AltaVista Example The primary search
interface can be found in the US: http://www.altavista.com/
http://www.av.com/ (These addresses all lead to the same
information.) Mirror site in UK: http://www.altavista.co.uk/
- Slide 61
- 61 Internet indexes: AltaVista: features Allows full text
searching of the WWW Allows advanced Boolean searching (in Advanced
mode) Offers relevance ranking of search results Offers a link to
an Internet subject directory (Looksmart) Offers links to systems
to find images, sounds, (multimedia) in the Internet Example
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- 62 Internet indexes: All the Web Example The search interface
can be found at: http://www.alltheweb.com/
http://www.alltheweb.com/ You can search the WWW and ftp servers.
The database is one of the biggest. Not only HTML and plain text
files, but also the full text of many Adobe PDF files is
indexed.
- Slide 63
- 63 Internet indexes: Google (Part 1) http://www.google.com/
Full-text searching is possible of many files that are available
through the WWW. Not only HTML and plain text pages are covered,
but also the first part is indexed of many files in other file
formats, such as Adobe PDF, Microsoft Word, Microsoft Excel,
Microsoft PowerPoint Rich Text Format Example
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- 64 Internet indexes: Google (Part 2) One of the most popular
systems in 2001, 2002, 2003 For retrieval an algorithm is used that
takes into account the links between WWW pages. A retrieved page is
ranked higher when many sites/pages point to it important
sites/pages point to it Example
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- 65 Internet indexes: Google refers to a thesaurus In Google,
the words used in a search query are returned to the user with
hyperlinks to a dictionary and to a thesaurus on the WWW, that can
be used partly free of charge. The thesaurus can of course show the
user synonyms, narrower terms, related terms for the word. So this
system can be used to expand a search query, so that the query
better covers the search concept. Example
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- 66 Internet indexes: from Google into a thesaurus Example
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- 67 !? Question !? Task !? Problem !? In spite of the popularity
of the Google Internet index, there are limitations in the search
features. Which limitations? In spite of the popularity of the
Google Internet index, there are limitations in the search
features. Which limitations?
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- 68 Internet indexes: Google limitations (Part 1) Google does
NOT offer/allow an unlimited number of search terms in a search
query manual or automatic truncation of words in a query manual or
automatic stemming of words in a query full Boolean search
formulations (OR, AND, brackets) a proximity/nearby operator in the
queries (such as NEAR) more or less automatic expansion of a search
query to include synonyms, narrower terms, translations
Example
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- 69 Internet indexes: Google limitations (Part 2) Google does
NOT offer/allow full-text searching of complete text in the case of
very long documents a relevance feedback mechanism Example
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- 70 Internet indexes: Google limitations (Part 3) Google does
NOT offer/allow powerful searching to find WWW documents that link
to some document in a given WWW site (WWW site citation searching),
as truncation is not possible in a Google query; only searching is
possible to find documents that link to a particular WWW document;
in other words, the URL of the WWW document as written in the query
must be perfect and cannot be truncated (AltaVista is superior in
this application, because it allows truncations in the search
queries) Example
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- 71 Internet indexes: Google limitations (Part 4) Google does
NOT offer/allow automatic classification/clustering/categorization
of retrieved WWW pages, to cope with the problem of the natural
ambiguity of meaning of the terms that were used in the search
query any evaluation of documents retrieved and offered as results
Example
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- 72 Internet indexes: Google limitations (Part 5) Google does
NOT offer/allow fact extraction from the information sources, in an
attempt to answer the query more directly than by offering only
links to documents a current awareness service (by email for
instance) Example
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- 73 Internet indexes: Google additional features Besides a
system to search for WWW pages, Google offers also a subject
directory searching for images/pictures on the WWW searching an
archive of Usenet messages + posting to Usenet groups searching for
news Thus Google has become a great integrator / aggregator.
Example
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- 74 Internet indexes: MSN Web Search Offered free of charge by
Microsoft. You can search for WWW content. Since 1998. Famous
system, because the search interface can be found with the search
functions that have been built into one of the most widespread
Internet browser, Microsoft Internet Explorer, and because it is
offered by http://search.msn.com/ http://search.msn.com/ Is based
on an Internet index created by another company. Example
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- 75 Internet indexes: Scirus Allows you to search for manually
selected scientific information (only) on the WWW. This includes
the peer-reviewed articles in the journals that are published in
ScienceDirect by Elsevier, that can be downloaded in full-text
format only when a fee has been paid to the publisher scientific
open archives files, that contain scientific research articles that
can be downloaded free of charge. The search interface:
http://www.scirus.comhttp://www.scirus.com Example
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- 76 Internet indexes: Scirus features Offered free of charge by
Elsevier. Is partly based on the Fast WWW search system that is
also used by Alltheweb. Offers access to information ordered
according to some classification system / taxonomy. Offers not only
access to files in html format, but also to files in PDF,
PostScript and other formats. Example
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- 77 Internet indexes: Teoma Allows you to search for information
on the WWW. Offers a feature that is not offered by most other
search systems: categorization = classification = refinement =
categorization = clustering of search results, to help the user
coping with the problem of ambiguity of meaning of the search query
that was made The search interface:
http://www.teoma.com/http://www.teoma.com/
- Slide 78
- 78 Internet indexes: Teoma example Example of coping with
ambiguity: searching for pascal gives results related to the
philosopher and to the computer programming language:
- Slide 79
- 79 Internet indexes: coverage / size of each index The indexes
grow and their size ranking is variable. Biggest systems in 2002:
Google ! AltaVista (Fast =) All the Web (serving also Lycos)
Systems based on the INKTOMI database of WWW pages, such as Hotbot,
MSN Web search,
- Slide 80
- 80 the complete WWW a global Internet index an index limited to
sources in/of a country or region Internet indexes: non-global,
regional systems
- Slide 81
- 81 Internet indexes: comparison with library catalogues Most
Internet indexes have a larger database than most catalogues.
Internet index databases do not correspond as well to the Internet
as a normal, good catalogue corresponds to the collection, because
the documents on the Internet change more often and their number is
growing fast. Most Internet indexes contain all the words of the
documents that they index, whereas catalogues only contain short
descriptions of the documents.
- Slide 82
- 82 Internet indexes: variations among various systems Besides
their common aims and characteristics, we can nevertheless see
differences, variations among the searchable Internet index
systems. To illustrate these variations and to assist Internet
users to make a decision on which search system to use, the
following list of some features and evaluation criteria can be
useful.
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- 83 Internet indexes: evaluation criteria - desiderata (1) Is
usage free of charge? How complete is the coverage? Is the coverage
good (or poor) for a particular geographic region? Is the coverage
good (or poor) for a particular type of documents? Is the
searchable database up to date? Is the database updated frequently?
Do the search results contain only few dead (broken) links?
- Slide 84
- 84 Internet indexes: evaluation criteria - desiderata (2) Is
spamming filtered out, to give other pages a better chance of
turning up in the result set? Can the system cluster presumed
duplicate documents in the results? Or does the system simply
eliminate presumed duplicate documents from its database?
- Slide 85
- 85 Internet indexes: evaluation criteria - desiderata (3) Does
the database system work with full text indexing of each document
that has a place in the database, so that full text searching is
possible? Is the complete text indexed and searchable, even for
very long documents?
- Slide 86
- 86 Internet indexes: evaluation criteria - desiderata (4) Are
the contents of meta-fields also indexed to make them
searchable?
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- 87 Internet indexes: evaluation criteria - desiderata (5) Does
the system index also the text in files on the web that consist of
non-ASCII codes to make these also searchable and retrievable? For
instance files in the format of the various versions of Microsoft
Word (DOC), Microsoft PowerPoint (PPT, PPS), Microsoft Excel Adobe
Acrobat Portable Document Format (PDF)
- Slide 88
- 88 Internet indexes: evaluation criteria - desiderata (6) Field
indexing, so that searching limited to the contents of a particular
field is possible? for instance: HTML title,HTML keywords, URL,
date, link,Java applet, text, image file, sound file,video
file...
- Slide 89
- 89 Internet indexes: evaluation criteria - desiderata (7) Does
the system offer powerful search options like searching for terms
composed of several words, in queries like word1 word2 with the
words enclosed in double quote characters truncation of words in a
query? Boolean search combinations? an unlimited number of search
terms in a query? proximity/nearby/adjacency searching, with
operators like word1 NEAR word2 or word1 ADJ word2
- Slide 90
- 90 Internet indexes: evaluation criteria - desiderata (8)
spelling check of search terms in the query, and suggesting
spelling variations? automatic expansion of the search terms in the
initial users query, to achieve a higher recall, for instance by
automatic stemming of words in a query including synonyms including
narrower terms including translations into several other
languages
- Slide 91
- 91 Internet indexes: evaluation criteria - desiderata (9) Can
the results be limited to a certain time period? For instance based
on the date of the file as noted by the server computer, or of the
most recent indexing of the file Is the user interface easy to
understand and efficient to use? Is a user interface offered in
your own language? Does the system rank the items in the result set
according to their presumed relevance?
- Slide 92
- 92 Internet indexes: evaluation criteria - desiderata (10)
Possibility to combine Boolean retrieval with relevance ranking of
results? Can the results be ordered according to date of the file
as noted by the server computer, or of the most recent indexing of
the file Can the results be ordered according to size?
- Slide 93
- 93 Internet indexes: evaluation criteria - desiderata (11) Can
the system rank the results (documents) on the basis of the number
of WWW hyperlinks to that document? The system does NOT place/rank
some results (documents) higher in the results list, on the basis
of payments by the producer of those documents to the search system
company. Are advertisements / sponsored links / sponsored results
clearly distinguished from normal (not sponsored) search results?
Good and detailed summary of each result available?
- Slide 94
- 94 Internet indexes: evaluation criteria - desiderata (12)
Short response times? Are mirror sites available closer to you for
faster response? Does the system offer a good presentation format
of each result (document/page/item)? For instance: are search terms
indicated / highlighted in the results? Any evaluation offered
(automatic?) of the quality of each result, besides ranking in an
order related to probable relevance and importance of the
results
- Slide 95
- 95 Internet indexes: evaluation criteria - desiderata (13) Can
all the results (documents) from the same site be grouped together
(clustered)? Are results (retrieved documents) grouped / classified
/ categorized / clustered by the search system, on the basis of the
subjects of the documents and are these presented as groups /
clusters / classes / categories to the user of the search system,
to assist the user in coping with the problems that can be caused
for instance by multiple meanings of words used in a search
query.
- Slide 96
- 96 Internet indexes: evaluation criteria - desiderata (14) Is
translation of documents offered free of charge? Is any fact
extraction from the information sources offered, in an attempt to
answer the query more directly than by offering only links to
documents? High stability and reliability? No large
variations/fluctuations in the results from identical searches at
different times.
- Slide 97
- 97 Internet indexes: evaluation criteria - desiderata (15) Term
suggestion: Does the system analyse the search results of the first
query, to find frequently occurring terms and to suggest these to
the user as new and potentially interesting additional query
terms?
- Slide 98
- 98 Internet indexes: evaluation criteria - desiderata (16)
Relevance feedback: Can the user indicate among the search results
of a first query good, relevant results and bad, irrelevant
results, so that the system can use this information to offer
better results in a second query?
- Slide 99
- 99 Internet indexes: evaluation criteria - desiderata (17)
Relevance feedback 2: even better: Can the user indicate among the
search results of a first query + good, relevant results, - as well
as bad, irrelevant results, so that the system can use this
information to suggest + additional, new interesting query terms
that can be included in a second query, - as well as query terms
that should be excluded in a second query?
- Slide 100
- 100 Internet indexes: evaluation criteria - desiderata (18)
Good documentation and online help? Good help desk available? Can
the search system provide updated results through electronic mail,
as a current awareness tool?
- Slide 101
- 101 Internet indexes: evaluation criteria - desiderata (19) Is
the search/query also submitted to another database to obtain more
results? for instance: to a book database to obtain book
descriptions besides WWW documents
- Slide 102
- 102 Internet indexes: evaluation criteria - desiderata (20)
Other services available besides the normal WWW index: index to
news resources, that is more frequently updated?! Internet subject
directory?! anonymous ftp file index? gopher index? searchable
Usenet newsgroups archive? White pages = people finder = addresses
=... WWW-based e-mail and e-mail address directories auctions
through WWW
- Slide 103
- 103 !? Question !? Problem !? Why do different Internet search
engines (in most cases) give different results for an identical
search? even though they have access to the same (all) documents on
the Internet
- Slide 104
- 104 Internet search systems: an overview of their relations
Some relations among the most important public Internet search
systems can be seen on a map in colours with hyperlinks, which is
available from http://www.bruceclay.com/searchenginechart.pdf
http://www.bruceclay.com/searchenginechart.pdf This map is kept up
to date (at least up to 2002).
- Slide 105
- 105 Internet information sources Coverage of Internet
directories and Internet indexes A global Internet index A global
Internet directory
- Slide 106
- 106 Global Internet search tools: a comparison Global Internet
directories Only a limited selection of Internet sources Browsing
information sources is easy Good for broad searches Global Internet
indexes About 1/3 of the Internet is covered by an index Searching
requires some skills and knowledge Good for specific, narrow
searches Multi-threaded search systems These get information from
directories and indexes Searching requires some skills and
knowledge Good when even 1 index does not yield information
- Slide 107
- 107 !? Question !? Problem !? Which information on the Internet
is not covered by many searchable Internet indexes?
- Slide 108
- 108 Internet indexes cover only a part of the Internet:
introduction (1) The visible part of Internet The hidden, invisible
part of Internet and the WWW, (that is not searchable using a
global index like AltaVista, Google...)
- Slide 109
- 109 Internet indexes cover only a part of the Internet:
introduction (2) Why can Internet indexes find only a part of what
is in fact available through the Internet? 1.Quantitative technical
limitations: Each Internet search system has indexed only a part of
the static WWW pages that are available for indexing. 2.Qualitative
technical limitations: Besides the static WWW pages that Internet
search engines try to cover, many other, quite different sources
exist, that are also available through the Internet, but that are
not incorporated in those search engines.
- Slide 110
- 110 Internet Internet indexes cover only a part of the
Internet: scheme WWW Databases and file archives accessible through
the Internet telnet ftp... telnet ftp... CGI, ASP,... Rapidly
changing information, such as news Information accessible only when
passwords are used Static indexable texts in the WWW ( = on HTTP
server computers) covered partly by Internet indexes Word files PDF
files
- Slide 111
- 111 Database accessible over the Internet: a famous example:
Medline/PubMed Example
- Slide 112
- 112 Internet indexes cover only a part of the Internet:
conclusion for users When you want to retrieve information about a
particular subject from the Internet, use not only WWW indexes, but
use also other sources accessible through the Internet databases!
(book and journal bibliographies, library catalogues, archives of
group messages, directories, atlases,) rapidly changing
information, such as news information accessible only when
passwords are used anonymous ftp file archives e-mail based
interest groups; Usenet newsgroups
- Slide 113
- 113 Gateways to Internet databases accessible free of charge
Most Internet search engines search classical, static WWW pages and
not databases accessible through the WWW. However, some systems
offer a gateway to search databases on the Internet. Examples:
http://invisibleweb.com/http://invisibleweb.com/
http://www.completeplanet.com/http://www.completeplanet.com/
http://www.invisible-web.net/http://www.invisible-web.net/ (See
also other more general directories/overviews/lists of Internet
information sources.)
- Slide 114
- 114 Example Gateways to Internet databases accessible free of
charge: invisibleweb
- Slide 115
- 115 Hybrid systems to find information on the Internet Some
systems require a search in words from the searcher, but they do
not rely on classical Internet indexes. Example: Ask Jeeves
- Slide 116
- 116 Example Hybrid systems to find information on the Internet:
Ask Jeeves Ask Jeeves tries to answer questions of searchers, by
analysing the natural language queries and by referring to selected
sources on the Internet. http://www.askjeeves.com/
http://www.ask.com/ http://www.aj.com/
- Slide 117
- 117 !? Question !? Task !? Problem !? How can you easily find
new pages that become accessible on the WWW about a particular
topic that is interesting for you?
- Slide 118
- 118 Current awareness services focusing on WWW pages:
introduction Tracking changes in one or more public access pages on
the WWW or finding new pages, is possible in an automated way, by
using one of the available, suitable, programs loaded on your
client workstation! example: the advanced version of Copernic that
is not available free of charge through alert services based on a
server on the WWW that track updates for the user/subscriber and
send alerts by email to the user/subscriber
- Slide 119
- 119 Current awareness services focusing on WWW pages: modified
versus new Several systems exist that can track changes /
modifications / updates in a particular existing WWW page for you,
even free of charge. Some systems can find new pages on the WWW for
you.
- Slide 120
- 120 Current awareness services focusing on WWW pages: Google
Alert Can discover relevant changed or new WWW pages for you in the
future. Is based on the external Internet index Google. Works with
search queries given by you that are stored on their server
computer. Free of charge, at least up to 2003.
http://www.googlealert.com/
- Slide 121
- 121 Current awareness services focusing on WWW pages: Google
Alert
- Slide 122
- 122 Online access information sources and services Public
access book databases
- Slide 123
- 123 Public access book databases: introduction Even in this age
of Internet-based information sources, a lot of information is
still distributed in the form of printed books. The contents of
most books is (still) not available on the Internet. Most general
Internet search tools do NOT allow you to find out about the
existence of books that may be interesting for you. So, specific
search tools to find books can be useful.
- Slide 124
- 124 Public access book databases: an overview (Databases by
publishers.) Fee-based databases by commercial providers Databases
by book distributors / bookshops! Online public access catalogues
of local libraries, national libraries (which produce and offer
normally their national bibliography)! big, famous libraries!!
(Databases of computer-based versions of books.)
- Slide 125
- 125 Public access book databases: which one to use? For years,
the market of bibliographic information on books was limited to the
services and databases of subscription-based bibliographic
providers. Nowadays, the WWW provides a key to unlock many
possibilities to find bibliographic information. Which book
database should be preferred for particular applications is not
clear for most librarians or end-users.
- Slide 126
- 126 Suitable book databases? AIMRECOMMENDED SYSTEMS Book title
search in general ? To search for book titles published before 1990
? To find book titles about a specific subject / topic ? To find
the price of a book ? To be informed regularly about new books
?
- Slide 127
- 127 Public access book databases by commercial producers To
find currently available books, some databases assembled by
commercial producers can be interesting. Example: Global Books in
Print These databases offer formal descriptions of books, prices of
the books, short descriptions of the contents with subject terms
However, access to such a database is not free of charge and can be
expensive (in comparison with alternatives).
- Slide 128
- 128 Public access book databases provided by bookshops To find
currently available books, the bibliographic databases assembled by
big bookshops are interesting. Several offer a good coverage and
are accessible free of charge. The added price information can be
useful for the acquisition and accounting department of a library
or if an individual user wants to buy a book. Some provide a
current awareness service, also free of charge.
- Slide 129
- 129 Book databases accessible free of charge: examples in
U.S.A. Amazon.com (US): http://www.amazon.com/
http://www.amazon.co.uk/ note: amazon, NOT amazone Subject
description is poor. http://www.amazon.com/http://www.amazon.co.uk/
Barnes and Noble (US): http://www.bn.com/ http://www.bn.com/
Examples
- Slide 130
- 130 Book databases accessible free of charge: examples in
Europe Blackwells on the Internet (International, academic books):
http://www.blackwell.co.uk/ http://www.blackwell.co.uk/ VLB for
books in German http://www.buchhandel.de/ http://www.buchhandel.de/
For books in French http://www.chapitre.com http://www.chapitre.com
Boeknet - De Nederlandse Internet Boekhandel (Dutch)
http://www.boeknet.nl/ http://www.boeknet.nl/ Examples
- Slide 131
- 131 Book databases accessible free of charge: for old books To
find used, secondhand, rare, hard-to-find, and out-of-print books
around the world: abebooks http://www.abebooks.com/
http://www.abebooks.com/ Examples
- Slide 132
- 132 Free public access bibliographic book database + price
comparisons Even comparisons of the catalogues of shops of books
(as well as of music, movies and many other goods) are available
free of charge. See for instance
http://www.bookfinder.com/http://www.bookfinder.com/
http://www.dealtime.com/http://www.dealtime.com/
- Slide 133
- 133 Example of an international public access dissertation
database The dissertation database of UMI is available from:
http://wwwlib.umi.com/dissertations/
http://wwwlib.umi.com/dissertations/ The most current two years are
available without charge. Examples
- Slide 134
- 134 Online Public Access Catalogues of libraries Mainly to find
older books, the catalogues of libraries can be useful. Most are
accessible online and free of charge.
- Slide 135
- 135 Online Public Access Catalogues = OPACs: definition Online
Public Access Catalogue: a term used to describe any type of
computerized library catalog offered to the public by online
login
- Slide 136
- 136 Online Public Access Catalogues of the big famous libraries
For instance: Library of Congress (USA) Their coverage is good.
They offer the best subject descriptions. Access is free of charge.
So they form excellent sources to find books about a particular
subject/topic.
- Slide 137
- 137 Online Public Access Catalogues: The Library of Congress,
U.S.A. >15 million books + >10 million other documents
Located in Washington DC, U.S.A. Accessible online via WWW Access
free of charge Offers good subject descriptions with the famous
Library of Congress Subject Headings (LCSH) Example
- Slide 138
- 138 Online Public Access Catalogues: The British Library
Accessible online via WWW: Since 2000:
http://blpc.bl.uk/http://blpc.bl.uk/ Access free of charge
Example
- Slide 139
- 139 Online Public Access Catalogues: The British Library:
screenshot Example
- Slide 140
- 140 Online Public Access Catalogues: catalogues of national
libraries National libraries are first of all an outstanding source
for the local publications. The national libraries are the most
reliable source for bibliographic searching and verification.
- Slide 141
- 141 Recommended book databases AIMRECOMMENDED SYSTEMS Book
title search in general Library of Congress, British Library,
Infoball To search for book titles published before 1990 National
libraries, Barnes&Noble, Infoball, Alapage, Abebooks To find
book titles about a specific subject / topic Library of Congress,
British Library, (Amazon) To find the price of a book Global Books
in Print, Infoball, online bookshops To be informed regularly about
new books Amazon, Alapage, Bol
- Slide 142
- 142 Public access book databases: evaluation criteria -
desiderata (1) Is usage free of charge? Wide coverage? Specialized
coverage of books in your preferred language? on particular
subjects / topics? published in a specific country? published in a
particular time period? of particular types (such as conference
proceedings)? Up to date? Frequent updates?
- Slide 143
- 143 Public access book databases: evaluation criteria -
desiderata (2) Does the database offer besides each formal book
descriptions also an abstract / summary / description of the
contents? a table of contents? reviews by readers? the price?
information about the publisher? titles of related books?
- Slide 144
- 144 Public access book databases: evaluation criteria -
desiderata (3) Full text indexing of each item in the database, so
that full text searching is possible? Field indexing, so that
searching for the contents of a particular field is possible? for
instance the title the date of publication the author the publisher
the language
- Slide 145
- 145 Public access book databases: evaluation criteria -
desiderata (4) Does the database producer improve retrieval by
adding subject terms, or by classifying the books in
categories
- Slide 146
- 146 Public access book databases: evaluation criteria -
desiderata (5) Powerful search options: truncation? stemming?
Boolean search combinations? combined field searching? proximity
searching? spelling check of your search terms? translation of your
search terms in several other languages?
- Slide 147
- 147 Public access book databases: evaluation criteria -
desiderata (6) Can the user browse through subject categories that
are used in the book database? Is a user interface offered in your
own language? Easy user interface? Relevance ranking of results?
Possibility to combine Boolean retrieval with relevance ranking of
results? Can results be limited to a certain time period? Short
response times?
- Slide 148
- 148 Public access book databases: evaluation criteria -
desiderata (7) Can the results be ordered according to date, size,
origin...? Good presentation of each result? For instance: Are
search terms highlighted? Can results be downloaded well structured
with field tags? (For instance to allow incorporation of the data
in another database.)
- Slide 149
- 149 Public access book databases: evaluation criteria -
desiderata (8) Does the system offer a current awareness service,
sending information on new titles that may be of interest to
you?
- Slide 150
- 150 Public access book databases: evaluation criteria -
desiderata (9) Are other services offered from the same site or
with the same interface? Is the system integrated with other
services? Additional services can be searchable databases of
videos, of music CDs, CD-ROMs, DVDs, all for sale also WWW-based
e-mail and e-mail address directories auctions through WWW
- Slide 151
- 151 Online access information sources and services Fee-based
online public access information services
- Slide 152
- 152 Types of online access information systems: free versus fee
A lot of the information on the Internet is available free of
charge, but another part is only accessible when a fee is paid to
the producer and / or the distributor. Some organisations pay these
fees for some sources and then organise access, so that the members
of the organisation can retrieve and exploit the information as if
it is free of charge. The first commercial computer systems that
make information available online were born around 1975. Most of
them are now also available through the Internet.
- Slide 153
- 153 Fee-based online access services: examples (Part 1)
Location of the computer(s)U.S.A. U.S.A. U.S.A. U.S.A., Taiwan, UK
Switzerland U.S.A. Name America On Line OCLC Ovid Technologies
CompuServe Cambridge Data-Star Dialog EBSCO Examples
- Slide 154
- 154 Fee-based online access services: examples (Part 2)
Location of the computer(s) U.S.A. U.S.A. U.S.A., The
Netherlands,... Germany - U.S.A. - Japan The Netherlands... Name
Elsevier ScienceDirect Factiva ISI (Web of Science, JCR,)
LexisNexis MSN (Microsoft) Prodigy Silver Platter STN
Swets-Blackwell (e-journals)... Examples
- Slide 155
- 155 Online information services: various names for similar
systems (fee-based) online (access) information service (fee-based)
online (access) computer service databank database vendor host
computer aggregator...
- Slide 156
- 156 Online information services: access methods Using generic,
common communications software through the telephone network
(telephone + modem) through X-25 data communication networks
through Internet, using client-server systems: telnet WAIS or
Z39.50 http (WWW)! (Examples: http://www.dialogweb.com;
http://www.datastarweb.com)http://www.dialogweb.comhttp://www.datastarweb.com
(Using client software dedicated to the particular service)
- Slide 157
- 157 Online information services: total size of their databases
In 1999: The big host systems and the public access WWW pages offer
a comparable quantity of information: WWW offered about 8 terabytes
(= 8 000 gigabytes) of text data (according to Lawrence and Lee
Giles, Nature, 1999, Vol. 400, pp. 107-109.) Dialog offered about 9
terabytes (= 9 000 gigabytes) (in 1998) 6 billion pages of text 3
million images
- Slide 158
- 158 Database hosts / distributors: evaluation criteria -
desiderata (1) Contract not required? A priori payment not
required? Satisfactory stability / history / evolution / future of
host? Low costs of data communication? Many databases available?
Whole records available (or only parts)? Frequent updates? Whole
database available? As one file or fragmented?
- Slide 159
- 159 Database hosts / distributors: evaluation criteria -
desiderata (2) Low price of access? Low price of information? Good
searching facilities? (cfr. desiderata for Internet indexes) Can
the indexes of more than one database be searched
simultaneously?
- Slide 160
- 160 Database hosts / distributors: evaluation criteria -
desiderata (3) Online indication of costs? Practice free of charge?
Good manuals, documentation and online help? Training courses
available? Quality? Good help desk available? Gateway service
offered?...
- Slide 161
- 161 Databases of online public access databases Example Gale
directory of databases ! Their coverage: online access databases
(databases accessible on CD-ROM) ...
- Slide 162
- 162 Databases of databases: Gale Produced in U.S.A. Not free of
charge Available in various formats: printed on CD-ROM online via
the host systems Data-Star, Dialog, with a payment required for
each use online through the Internet through various hosts, for a
fixed price per year to be paid in advance
- Slide 163
- 163 Online access information sources and services Online
access databases about journal articles
- Slide 164
- 164 Online access databases about journal articles: overview
Thousands of fee-based online access databases offer bibliographies
or full-texts of journal articles in particular subject domains and
published by many publishers. Many publishers offer searchable
bibliographies, but only of their own publications. (for instance
Emerald, Elsevier) Only few large databases offer access to
bibliographies of articles published in journals from many
publishers, free of charge.
- Slide 165
- 165 Online access databases about journal articles: Ingenta (1)
Ingenta Journals allows you to search a bibliographic database of
millions of journal articles, including titles, authors, in many
cases abstracts. Searching is free of charge. Example
- Slide 166
- 166 Online access databases about journal articles: Ingenta (2)
Payment is required to receive the full text of an article. Ingenta
has acquired Uncover in 2000. Available from
http://www.ingenta.co.uk/http://www.ingenta.co.uk/
http://www.ingenta.com/http://www.ingenta.com Example
- Slide 167
- 167 Online access databases about journal articles:
Article@INIST Article@INIST allows you to search in a bibliographic
database, NOT full-text, (Journal articles, journal issues, books,
reports, conferences, doctoral dissertations) at the Institut de
l'Information Scientifique et Technique, France. Does not offer
usage of classification or thesaurus. Searching is free of charge.
Available from
http://form.inist.fr/public/eng/conslt.htmhttp://form.inist.fr/public/eng/conslt.htm
Payment is required to receive the full text of an article.
Example
- Slide 168
- 168 Online access databases about journal articles: Infotrieve
Infotrieve allows you to search free of charge in a bibliographic
database of the articles of more than 20 000 journal titles and
conference proceedings, NOT full-text. Available from
http://www3.infotrieve.com/http://www3.infotrieve.com/ Payment is
required to receive the full text of a document. Current awareness
services are also offered free of charge: the table of contents of
new issues of the journals that you have selected are sent to you
by email. Example
- Slide 169
- 169 Online access databases about journal articles: Scirus This
is a specialised Internet index that allows you to search for
selected scientific information (only) on the WWW. This includes
the peer-reviewed articles in the journals that are published in
ScienceDirect by Elsevier. An article can be downloaded in
full-text format only when a fee has been paid to the publisher The
search interface: http://www.scirus.comhttp://www.scirus.com
Example
- Slide 170
- 170 Online access databases about journal articles: Scirus
features Offered free of charge by Elsevier. Is partly based on the
Fast WWW search system that is also used by Alltheweb. Offers
access to information ordered according to some classification
system / taxonomy. Example
- Slide 171
- 171 Online access databases: Web of Knowledge The Web of
Science or more recently the Web of Knowledge offers access through
the WWW to a database of bibliographic descriptions of scientific
journal articles in all subject domains. This database is (only)
available to members of organisations / institutes / companies /
consortia that pay a yearly fee to the producer/publisher of the
database. This database is not only suitable for subject searching,
but also for citation searching.
- Slide 172
- 172 Online access information sources and services Electronic
newsletters and journals
- Slide 173
- 173 Electronic newsletters and journals: introduction Since the
end of the 1990s, electronic journals have become a new
communication medium that cannot be neglected. Author / Sender
Editor Reader / Receiver
- Slide 174
- 174 Electronic newsletters and journals: various types and the
price of access We can distinguish various types: equivalents of a
version printed on paper published almost simultaneously print
version published long time before electronic version = deliberate
long delay for the electronic version purely electronic
publications Price of access: from free of charge to very
expensive
- Slide 175
- 175 Electronic newsletters and journals: access and
distribution methods Many different methods are used: anonymous ftp
gopher WAIS / Z39.50 electronic mail, listserv,... Usenet News
loaded on local systems in universities or institutes http, WWW !
Open Archives Harvesting Protocol + http, WWW
- Slide 176
- 176 Electronic newsletters and journals through the WWW The WWW
has become the most important platform for access to electronic
newsletters and journals.
- Slide 177
- 177 Electronic newsletters and journals: example Example
- Slide 178
- 178 Electronic newsletters and journals: problems and
challenges There is no central database with all article titles,
summaries, and full contents. There is not even a central, complete
and up to date directory of journal titles. There is no standard
licensing/pricing method. Not all electronic journals are
accessible through 1 user interface. Many passwords must be used.
Archiving (By whom? Forever?)
- Slide 179
- 179 !? Question !? Task !? Problem !? Find out how you can
efficiently access electronic journals from your institute.
- Slide 180
- 180 Directory of Open Access Journals http://www.doaj.org/ the
Directory of Open Access Journals is a directory of electronic
journals that can be accessed free of charge (since May
2003)http://www.doaj.org/
- Slide 181
- 181 Directory of Open Access Journals: screenshot
- Slide 182
- 182 Online access information sources and services Finding
multimedia files on the Internet
- Slide 183
- 183 Finding multimedia files on the Internet: introduction
Several public access search systems are available free of charge
to search the Internet for multimedia files: images / pictures
(either artwork, either photos, or both) sound / audio files
(music, speeches,...) video
- Slide 184
- 184 Finding images on the Internet: introduction Several public
access search systems are available free of charge to search for
images / pictures (either artwork, either photos, or both) on the
Internet. When searching for images, the search results from such a
system offer not only links to the image files on the Internet, but
also directly small versions of the images (so-called
thumbnails).
- Slide 185
- 185 Examples Finding images on the Internet: examples of search
engines (1) http://alltheweb.com/ !!http://alltheweb.com/
http://gallery.yahoo.com/ !http://gallery.yahoo.com/
http://images.google.com/ !!! or through
http://www.google.com/http://images.google.com/http://www.google.com/
http://multimedia.lycos.com/ http://www.altavista.com/ !! (also
audio and video, choose not the normal text search, but IMAGES in
the user interface.)http://www.altavista.com/
- Slide 186
- 186 Examples Finding images on the Internet: examples of search
engines (2) http://www.ask.com/ or http://www.aj.com/ or
http://aj.com/ Ask Jeeves. Offers no indication of the number of
images retrieved, which is a disadvantage when many pictures are
found, but only a few can be seen at the time.http://www.ask.com/
http://www.aj.com/ http://aj.com/ http://www.ditto.com/
!http://www.ditto.com/
- Slide 187
- 187 Examples Finding images on the Internet: screen shot of a
Google image search
- Slide 188
- 188 !? Question !? Task !? Problem !? Use a specialised search
engine to find images about a particular subject on the
Internet.
- Slide 189
- 189 !? Question !? Task !? Problem !? Why can we say that most
of well-known systems to search for images on the WWW are in fact
text searching systems?
- Slide 190
- 190 Online access information: future trends An increasing
amount of information becomes available online. A growing amount of
this online information becomes available free of charge. The
quality of server and client software is growing. A consequence is:
An increasing number of end-users searching for information
online.
- Slide 191
- 191 Online access information: conclusion In the case of simple
information needs, the WWW and the search tools can work like
magic. However, in the case of more complicated information needs,
there is still is no magic button that brings you immediately to
all the required information.
- Slide 192
- 192 Evaluating the quality of information Documentary
information sources: evaluating their quality
- Slide 193
- 193 Documentary information sources: evaluating their quality
We should always be critical when using information sources, in
view of the widely varying degrees of quality of information
sources, and of the costs associated with searching, finding, using
information.
- Slide 194
- 194 Documentary information sources: evaluation criteria (1) Is
the information valid, reliable, trustworthy, genuine, authentic?
Is the author honest? Is the source objective, not subjective,
without cultural or political or ideological or commercial bias? Is
the origin an individual or a company or an organisation? Is the
publication sponsored by some company or organisation?
- Slide 195
- 195 Documentary information sources: evaluation criteria (2) Is
the information accurate, correct? Who is the author or producer?
Has the source an author or a producer with a high expertise, a
good reputation, good qualifications? Can the author be contacted
for clarification or discussion? Was the information reviewed,
edited, improved, corrected, censored, approved, verified, before
publication? Do experts agree on the information provided?
- Slide 196
- 196 Documentary information sources: evaluation criteria (3) Is
the information source unique? Does it offer a great amount of
primary information, which is not obtainable from other sources? Is
the information complete? Is the work available in its entirety?
Does the source offer a wide coverage? Is the source comprehensive,
substantive? Is the information current enough, up to date? Is a
publication date provided? Is an expiration date provided?
- Slide 197
- 197 Documentary information sources: evaluation criteria (4)
Does the document provide suitable references, so that you can
verify statements and find older suitable information sources? Good
clear format and lay-out of the information / User-friendly
information system / Easy for users to orientate themselves within
the resource and to find their way around it? Good user support /
Good customer support? Is the type of distribution medium
appropriate? (print, e-mail, online,...)
- Slide 198
- 198 Documentary information sources: evaluation criteria (5) Is
the information what you want? If not, then reassess your needs and
consider other types of information as well.
- Slide 199
- 199 Documentary information sources: evaluation criteria (6) Is
the information suitable for your level of understanding of the
subject? Is the document popular, suitable for the general public,
for students, for professionals, for scholarly/academic use? Does
it report new, primary research (survey, experiment, observation,
measurement, invention) or is it a review of sources published
earlier? Does the information repeat or confirm what you already
know, or is it complementary, contradictory, new?
- Slide 200
- 200 Evaluating the quality of information Computer-based
information sources: evaluating their quality
- Slide 201
- 201 Computer-based information sources: The Internet Detective
A tutorial in English about how to assess the quality of WWW-based
information resources can be accessed online free of charge through
the WWW: http://www.netskills.ac.uk/TonicNG/cgi/sesame?detective
http://www.netskills.ac.uk/TonicNG/cgi/sesame?detective
- Slide 202
- 202 Do you have any questions? Suggestions for a discussion?
These slides are available through the WWW from
http://www.vub.ac.be/BIBLIO/nieuwenhuysen/presentations/ (note:
BIBLIO and not biblio)
- Slide 203
- 203 Thank you for your attention and for your contributions to
the discussions! These slides are available through the WWW from
http://www.vub.ac.be/BIBLIO/nieuwenhuysen/presentations/ (note:
BIBLIO and not biblio)