Internet Resources Discovery (IRD)

Internet Resources Discovery (IRD)

The Invisible Web

T.Sharon-A.Frank2

Contents

• What is the Invisible Web?• How big is the Invisible Web?• Why is there an Invisible Web

(and what’s in it)? • Case study – patent search• How to find Invisible Web resources?

T.Sharon-A.Frank3

What is the Invisible Web?• Called also “Deep Web” in contrast to the “Surface Web”,

which is the Visible Web.• The term “Invisible Web” relates to content of pages that are

available and accessible on the Web, but are not accessible and not indexed by the regular SEs, and includes mostly:– searchable databases– excluded pages

• These pages do not appear in the SEs search results.• Finding information on the Invisible Web is available using

direct access or using Specialized SEs.• The extent of the Invisible Web is larger than the Visible Web.

T.Sharon-A.Frank4

How Big is the Invisible Web?

According to BrightPlanet study (2000):• Deep web (Invisible web) is 500 times larger.

– Number of search utilities:• 45,000 search engines on the surface web. • 200,000 searchable databases within the deep web.

– Number of documents:• 1 billion documents on the surface web. • 550 billion documents within deep web.

• Deep web quality is 1,000 times greater.

• 95% of deep web information is publicly available.

http://www.brightplanet.com/technology/deepweb.asp

T.Sharon-A.Frank5

Visible vs. Invisible Web

T.Sharon-A.Frank6

More Details (1)

• Public information on the deep Web is currently 400 to 550 times larger than the commonly defined World Wide Web.

• The deep Web contains 7,500 terabytes of information compared to 19 terabytes of information in the surface Web.

• The deep Web contains nearly 550 billion individual documents compared to the 1 billion of the surface Web.

• More than 200,000 deep Web sites presently exist.

T.Sharon-A.Frank7

More Details (2)

• Sixty of the largest deep Web sites collectively contain about 750 terabytes of information - sufficient by themselves to exceed the size of the surface Web forty times.

• On average, deep Web sites receive 50% greater monthly traffic than surface sites and are more highly linked to than surface sites.

• However, the typical (median) deep Web site is not well known to the Internet-searching public.

T.Sharon-A.Frank8

More Details (3)

• The deep Web is the largest growing category of new information on the Internet.

• Deep Web sites tend to be narrower, with deeper content, than conventional surface sites.

• More than half of the deep Web content resides in topic-specific databases.

T.Sharon-A.Frank9

More Details (4)

• Total quality content of the deep Web is 1,000 to 2,000 times greater than that of the surface Web.

• Deep Web content is highly relevant to every information need, market, and domain.

• A full ninety-five per cent of the deep Web is publicly accessible information -- not subject to fees or subscriptions.

T.Sharon-A.Frank10

Invisible Web?!

The Invisible Web

google

T.Sharon-A.Frank11

Is it Really that Big?

• Some argue that the Invisible Web is actually only 50-80 times bigger than the Invisible Web.

T.Sharon-A.Frank12

Deep Web Growing Faster than Surface Web

T.Sharon-A.Frank13

Original deep content exceeds all printed global content

T.Sharon-A.Frank14

The Size Today???

• 2000 - 1:550 (with source)

• 2004 - 10:1000 (estimate) - 2 orders of magnitude more

T.Sharon-A.Frank15

Why is there an Invisible Web? (1)

1. Specialized searchable databases:– Have dynamic pages.– Require parameters and user judgment.– Require user and password.

2. Script-based pages:– Include “?” in their URL.– Hazard to SEs – traps.

T.Sharon-A.Frank16


3. Real-time, constantly changing, content.

4. Very large websites are partially indexed.

5. Private/secret websites:– Internal companies portals.

– Excluded from SEs (using robots.txt or similar schemes).

T.Sharon-A.Frank17


6. Multimedia (and other formats) files– Special formats

– Examples: PDF, DOC, PPT, GIF, Flash

– Some of the SEs can’t, or won’t index these.

T.Sharon-A.Frank18


7. Additional reasons (mostly spam related or resources saving):– File size– Number of words in the page– Pages requiring cookies– Other spam characteristics– Multimedia files– Files and URLs with special

characters.

T.Sharon-A.Frank19

8. Non-linked pages (no incoming/inbound links).9. Pages on servers with dynamic IP.

• For example, 5% of the Internet is not connected!The Internet is partitioned and there exists “Dark Address Space”, or prefixes that are not reachable for one provider but that are available from other providers for long periods of time.

5% of the total number of prefixes in the Internet or tens of millions of end hosts.

Source: Arbor Networks -http://www.arbornetworks.com/downloads/research38/dark_address_space.pdf


T.Sharon-A.Frank20

Invisible

T.Sharon-A.Frank21

The Invisible Web is mostly topic databases

T.Sharon-A.Frank22

Databases (1)

• Tens of thousands of databases in different topics exist.

• The SEs know many databases, but not their content.

• Entry to many databases is blocked, the SE knows its URL (main page), but not the information inside!

T.Sharon-A.Frank23

Databases (2)

• Searching these databases requires entry via the site user interfaces, and often also registration/password/cookies.

• The advantage of using the database’s user interface is that it is specialized and designed to get the best results searching that specific information.

T.Sharon-A.Frank24

Specialized interface

VS.

T.Sharon-A.Frank25

Topics of databases (1)

• Auction• Public, government

information• Expert directories• Buyer’s guides• Scientific databases

from educational institutions and research labs

• News & magazine archives

• Discussions• Mailing list archives• Product reviews• Legal databases• Shopping catalogs• Medical databases

T.Sharon-A.Frank26

Topics of databases (2)

• Product support knowledge bases

• Phone numbers, address, and email databases

• and much more

• Dictionaries

• Thesauri

• Patent databases

• Trademark databases

• Genealogy and surname lists

T.Sharon-A.Frank27

Sites by Subject Area

0.00% 5.00% 10.00% 15.00%

Health

Government

Engineering

Employment

Education

Computing/Web

Business

Arts

Agriculture

Series1

0.00% 5.00% 10.00% 15.00%

Travel

Shopping

Science, Math

References

Recreation, Sports

People, Companies

News, Media

Lifestyles

Law/Politics

Humanities

Series1

T.Sharon-A.Frank28

Example Databases (1)

• WebDietitian– http://www.webdietitian.com

• AnimalSearch – http://animalsearch.net– A database for family-safe animal-related sites.

• NatureServe Explorer– http://www.natureserve.org/explorer– Online encyclopedia, provides authoritative

conservation information on plants, animals, & ecological communities.

T.Sharon-A.Frank29

Example Databases (2)

• Search Systems– Public systems: courts, criminal records, birth, death,

marriages, recalls, etc.– http://www.searchsystems.net/

• PubMed– Provides access to 14 million + MEDLINE citations– http://www.ncbi.nlm.nih.gov/entrez/query.fcgi

• MedlinePlus– Trusted Medical Information– http://www.medlineplus.gov/

• National Library of Medicine– Directory of trusted medical information – http://www.nlm.nih.gov

T.Sharon-A.Frank30

Advantages of such databases• Quality of Content (Authority)• Deep Content on Subject Area (Comprehensiveness) • Focused Databases (Limited Scope) Smaller Universe

of Documents to Search (Maximize Precision/Recall) • Material Unavailable Elsewhere on the Web

(Uniqueness)• Many Options to Limit, Sort, Interact with the Data

(Maximize Precision)• Timeliness vs. Time Lag of General Search Tools

(Currency)

T.Sharon-A.Frank31

Will the Invisible Web become Visible?

Definitely!

• Using intelligent SEs.

• After a while, new information is being updated in SEs that can access the invisible web, and make it visible.

T.Sharon-A.Frank32

Google and the Invisible Web

• Google’s Search “By Number” Service, examples:– UPS tracking numbers: "1Z9999W99999999999"

– FedEx tracking numbers: "999999999999"

– USPS tracking numbers: "9999 9999 9999 9999 9999 99"

– Vehicle ID (VIN) numbers: "AAAAA999A9AA99999"

– UPC codes example: "073333531084"

– Telephone area codes: "650"

– Patent numbers: "patent 5123123" (Need to put the word "patent" before your patent number).

– Google Scholar

• http://www.google.com/help/features.html#number

T.Sharon-A.Frank33

Yahoo Shortcuts• Yahoo provides a lot of “shortcuts” to retrieve

information:– Gas prices– Exchange rates– Hotels– Airport Information– Sports Scores– Stock Quotes– and many more

• http://help.yahoo.com/help/us/ysearch/tips/tips-01.html

T.Sharon-A.Frank34

Case Study - Patents

• Searching for “CD box” in patent abstract.

• Google’s Search by Number

• USPTO

• FreePatentsOnline

T.Sharon-A.Frank35

Google’s Search by Number

T.Sharon-A.Frank36

USPTO Database

T.Sharon-A.Frank37

USPTO Advanced Search

T.Sharon-A.Frank38

Free Patents Online

T.Sharon-A.Frank39

Free Patents Online (Continuation)

T.Sharon-A.Frank40

Searching Database “CD box”

T.Sharon-A.Frank41

Searching Google

Example: Irrelevant50 results – mostly irrelevant

T.Sharon-A.Frank42

Is the Invisible Web Invisible ?

GoogleYahoo!

Google

X

T.Sharon-A.Frank43

How to Find Invisible Web Resources?

Search for sources – not information!

• Two-step searching in general search engines.

• Specialty Search Engines

• Subject Directories

• Digital Libraries

T.Sharon-A.Frank44

Two-Step Searching

• Use general search engine (such as Google) to search for a good database, then search for the information inside that database/website search engine.

• Examples words to add in the query:– database– association– tutorial– demographics– “how to”– webcam– streaming video + search engine– encyclopedia– product review

T.Sharon-A.Frank45

Invisible Web Pathfinders• Sherman-Price Invisible-Web Directory

http://www.invisible-web.net/

• CompletePlanet http://www.completeplanet.com

• Beaucoup http://www.beaucoup.com

• Turbo10 http://turbo10.com/

T.Sharon-A.Frank46

Sherman-Price Invisible-Web directory

T.Sharon-A.Frank47

Invisible-Web directoryPeople Search

T.Sharon-A.Frank48

Complete Planet

T.Sharon-A.Frank49

Beaucoup (1)

• Over 2500 engines

• The engines listed on the main site are "free information" sites -- a *lot* of information.

• Subject Directory/Annotated

T.Sharon-A.Frank50

Beaucoup (2)

T.Sharon-A.Frank51

Turbo10 (1)

T.Sharon-A.Frank52

Turbo10 (2)

T.Sharon-A.Frank53

Turbo10 (3)

T.Sharon-A.Frank54

Turbo10 – Edit Collections

T.Sharon-A.Frank55

More Invisible Web Pathfinders

• Librarianas’ Index to the Internet http://www.lii.org

• MeL Michigan eLibrary http://www.mel.org/

• Internet Scout Project http://scout.wisc.edu/

• Infomine http://infomine.ucr.edu/

• More: http://www.calvin.edu/library/searreso/internet/webdirec.stm

T.Sharon-A.Frank56

References• http://websearch.about.com/od/invisibleweb/• http://www.shelton.cc.al.us/library/lbs102/

lbs102session12.html• http://www.lib.berkeley.edu/TeachingLib/Guides/

Internet/InvisibleWeb.html• http://www.campus-technology.com/article.asp?

id=7477• http://www.searchengineoptimising.com/optimisation• http://www.press.umich.edu/jep/07-01/bergman.html

Internet Resources Discovery (IRD)

Documents

Transcript of Internet Resources Discovery (IRD)