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Information Seeking Behavior
LIS 510
Introduction
• Every day we are deluged by data– It is received through our five senses, which are
continuously at work
• Wide variety of input sources– Written material (hard copy and electronic)– Auditory (speech, radio, CDs, etc.)– Imagery (photographs, graphs, etc.)– Video (TV, movies, etc.)
Information Overload
• “The greatest problem of today is how to teach people to ignore the irrelevant, how to refuse to know things, before they are suffocated. For too many facts are as bad as none at all.” (W.H. Auden)
Information Theory
• Claude Shannon, 1940’s, studying communication
• Ways to measure information – Communication: producing the same message at its destination as
that seen at its source
– Problem: a “noisy channel” can distort the message
• Between transmitter and receiver, the message must be encoded
• Semantic aspects are irrelevantNoise
Channel
Receiver Desti-nation
Message source
Trans-mitter
Information Theory
• Better called “Communication Theory”• Communication may be over time and space
StorageSourceDecoding
(Retrieval/Reading)Encoding
(writing/indexing)Destination
Message Message
Source DecodingEncoding Destination
Message Message
Channel
What kinds of information are there?
• Text– books, periodicals, WWW, memos, ads– published/refeered
• Film
• Photos, other Images
• Broadcast TV, Radio
• Telephone Conversations
• Databases
How much information is there?
Gigabyte 10^9 bytes 1000 megabytes
Terabyte 10^12 bytes 1000 gigabytes
Petabyte 10^15 bytes 1000 terabytes
Exabyte 10^18 bytes 1000 petabytes
How Much Information?
• Stored Information– Print
– Film
– Optical
– Magnetic
• Communicated– Internet
– Broadcast
– Phone
• Annual Production– Books 968,735 = 8 Terabytes (compressed
image)
– Newspapers 22643 = 25 Terabytes – Journals 40000 = 2 Terabytes– Magazines 80000 = 10 Terabytes– Office Documents 12x10^9 pages = 312 Terabytes
– TOTAL 357 Terabytes (1824 scanned, 35 text)
• Library of Congress Printed book collection– About 18 Million books– About 130 Terabytes (compressed image)– For all of LC we should also assume
• 13M photographs, 5MB each = 65 TB• 4M maps, say 200 TB• 500K files, 1GB each = 500 TB• 3.5M sound recordings, ~2000 TB• Grand total: 3 petabytes (~3000 terabytes)
• Books in Print – 3.2 Million titles– About 26 Terabytes
Film and Image
• Film– Photographs = 410 Petabytes per year– Movies = 16 Terabytes (Commercial
Production of about 4000 films)– X-Rays = 12 Petabytes
Optical Media
• CD-Music 90,000 items = 58 TB
• CD-ROM 3,000 items = 3 TB
• DVD-Video 5,000 items = 22 TB
• Total 83 TB
Magnetic Media
• Audio Tape 184,200,000 = 184.2 Petabytes
• Video Tape 355,000,000 = 1420
• Floppy disks = 0.07
• Removable disks = 1.69
• Hard Disks = 500
Medium Type of content Terabytes/Year Terabytes/Year Upper Bound Lower Bound Paper Books 8 7 Newspapers 25 20 Periodicals 12 12 Office documents 312 312 SUBTOTAL 357 351Film Photographs 410,000 100,000 Cinema 16 16 X-Rays 12,000 12,000 SUBTOTAL 422,000 112,016Optical Music CDs 58 40 Data CDs 3 3 DVDs 22 22 SUBTOTAL 83 65Magnetic Camcorder 300,000 300,000 Disk drives 2,555,000 1,000,20 SUBTOTAL 2,855,000 1,300,200TOTAL 3,277,440 1,412,632
Current Size of Web
• There are an estimated 2.1 Billion pages on the Web– About 21 Terabytes– About 7500 further Terabytes in web-accessed DBs.
• 610 Billion email messages per year = 11285 TB• Internet Traffic is doubling every 100 days - An
estimated 62 Million Americans now use the internet Radio took 38 years to get 50 M listeners, TV took 13 years, the Net took 4 years...
Internet Hosts: 1989-2005
0
100000
200000
300000
400000
500000
600000
700000
800000
900000
1000000
1989
1991
1993
1995
1997
1999
2001
2003
2005
hosts
Projected Voice and Data Traffic
0
5000
10000
15000
20000
25000
30000
1996 1997 1998 1999 2000 2001 2002
VoiceData
Language Distribution of Web Content
English J apaneseGerman FrenchChinese SpanishItalian SwedishMalay KoreanPortuguese DutchDanish CzechFinnish RussianPolish HungarianNorwegian EstonianGreek BulgarianCroatian BasqueThai TurkishArabic AlbanianOthers & Unknown
Language Distribution on a 634 Million Web Pages Corpus
Language Number of Docs PercentageEnglish 453,685,690 71.5288%Japanese 43,271,080 6.8222%German 32,253,563 5.0851%French 11,107,994 1.7513%Chinese 9,642,450 1.5202%Spanish 6,965,560 1.0982%Italian 5,638,827 0.8890%Swedish 4,392,709 0.6926%Malay 3,619,227 0.5706%Korean 3,200,762 0.5046%Portuguese 3,014,294 0.4752%Dutch 2,745,610 0.4329%Danish 1,911,677 0.3014%Czech 1,428,385 0.2252%Finnish 1,312,932 0.2070%Russian 1,150,127 0.1813%Polish 952,716 0.1502%Hungarian 760,162 0.1198%Norwegian 607,211 0.0957%Estonian 456,613 0.0720%Greek 393,360 0.0620%Bulgarian 392,777 0.0619%Croatian 310,237 0.0489%Basque 258,074 0.0407%Thai 99,691 0.0157%Turkish 81,218 0.0128%Arabic 38,167 0.0060%Albanian 17,779 0.0028%Others & Unknown 44,561,062 7.0256%Total 634,269,953 100%
Human Memory
– Landauer 86: Human brain holds 200MB• looked at rate of information intake and rate of
forgetting, and amount of information adults need for normal tasks
– 6B people on earth implies total memory of all people alive about 1,200 petabytes
– Another way: • estimate that people take in a byte/sec• lifetime 250,000 days or 2B sec• result is 2 GB (doesn’t count synthesizing new info)
Data and Information
• These two terms are quite often used interchangeably– used without any definitions or explanation
• There are no standard definitions for these two terms
• Two possible definitions:
Data and Information (cont.)
• Data– items such as text, facts, numbers, images or
sounds that may or may not be useful for a particular purpose
• Information– data which has been processed so that its form
and content are appropriate for a particular purpose
Intuitive Notion
• Information must– Be something, although the exact nature (substance,
energy, or abstract concept) is not clear;
– Be “new”: repetition of previously received messages is not informative
– Be “true”: false or counterfactual information is “mis-information”
– Be “about” something
• This human-centered approach emphasizes meaning and use of message
Knowledge
• Quite often the terms information and knowledge are used interchangeably
• One possible definition of knowledge– a combination of information, instincts, rules,
ideas, procedures and experience that guide actions and decisions
Knowledge (cont.)
• Two types of knowledge– Tacit
• also called implicit, private or personal knowledge
• knowledge held by an individual; may not have been articulated or may not be articulatable
– For example, how does Michael Jordan accomplish his “slam dunks”
Knowledge (cont.)
– Explicit• also called public or social knowledge
• expressed in a form that makes it available to others– usually in a written form, but may be in other forms such
as verbal
Continuum
• Quite often data, information and knowledge are expressed as a continuum:
• Data => Information => Knowledge
Pyramid
• Data, information and knowledge are also depicted as a pyramid– a distillation occurs as we move up the pyramid
• data is “raw material”
• as data is processed, information is distilled from it and the resulting amount is smaller in size; the same result is experienced in going from information to knowledge
Wisdom
Long term goal should be the acquisition of wisdom
– but there is not much discussion in the literature or in the media
The current situation was aptly described by T.S. Eliot:
– “Where is the wisdom we have lost in knowledge? Where is the knowledge we have lost in information?”
Wisdom (cont.)
Wisdom connotes the ability to acquire and use knowledge and information judiciously, possessing the power of judging rightly and following the soundest course of action based on knowledge, skill, experience and understanding.
Information Hierarchy
• Data– The raw material of information
• Information– Data organized and presented by someone
• Knowledge– Information read, heard or seen and understood
• Wisdom– Distilled and integrated knowledge and understanding
What is Data?
• Represented by shapes or symbols that require cognitive skill to decipher
• May not provide a context to fully understand its meaning
e.g.
10,000,000
5,000,000
What is Information?
• Involves process of reception, recognition and conversion
• May involve a ‘novelty’ factor--a new piece of data
• May have multiple interpretations resulting in ‘public’ and ‘private’ information
e.g.
Joe won
$10,000,000 in the lottery last year and $5,000,000 more this year.
What is Knowledge?
• Is created/acquired from a collection of information
• Knowledge builds on a foundation of accurate information and can be passed on to others
e.g.
Joe has been paying a lot of taxes because of his lottery winnings and the brand new mansion he bought.
What is Wisdom/Insight?
• Represents highest level of complexity in chain of concepts
• Difficult to impart via a storage medium
• Argued to exist only within an individual
e.g.
He who has money has friends.
Where is the Life we have lost in living?Where is the wisdom we have lost in knowledge?Where is the knowledge we have lost in information?
-- T.S. Eliot, “The Rock”
Where is the information we have lost in data?
Whom Do People Ask for Information?
• People immediately present• People they know• People they trust
– “Gatekeepers”– People in authority generally– People with cognitive authority
• Teachers• Librarians
How Do People Ask for Information?
• At the moment of need
• By the easiest available route
• By what they expect will give them the most suitable answer
• By what they expect will give them the most accessible answer
Information and People
• Information reinforces social bonds
• People exchange familiar information
• People continue to believe erroneous information
• People say they value information (more than they use it)
• People want a known available source
Limits to Information
• People do not want information that will upset them
• People do not want information that might upset them
• People do not want more information than they can store
• People do not want more information than they can process
• People must eventually stop getting information and act on what they know
Dangers of Information
• Information might be erroneous• Information might be deliberately misleading• Information might be contradictory• Information might be so excessive as to paralyze action• Information may cost more than its worth• Relying on authority may be better than information• Possessing information may make one a too conspicuous
social figure• Possessing information may make one a challenge to
authority
Storing Information
• People do not want more information than they can store
• Immediate storage:– Short and long term memory– Active knowledge
• People need more information than they can store immediately:– “At hand”– “In the library”– “On the web”
Information Wants and Needs
• What people truly need
• What people recognize they need
• What people are willing to admit they need
• What people truly want now
• What people think they want now
• What people say they want now
The Standard Retrieval Interaction Model
Standard Model Assumptions
• Maximizing precision and recall simultaneously
• The information need remains static
• The value is the resulting document set
Problems with Standard Model
• Users learn during the search process– Scanning titles of retrieved documents– Reading retrieved documents– Viewing lists of related topics– Navigating hyperlinks
• Some users don’t like long disorganized lists of documents
Berry-Picking as an Information Seeking Strategy
• Standard IR model– Assumes the information need remains the
same throughout the search process
• Berry-picking model– Interesting information is scattered like berries
among bushes– The query is continually shifting
Berry-Picking Model (cont.)
• The query is continually shifting
• New information may yield new ideas and new directions
• The information need– Is not satisfied by a single, final retrieved set– Is satisfied by a series of selections and bits of
information found along the way
Systems View (cont.)
Data enters the system and are converted into information through a process of formatting, filtering and summarizing.
– knowledge is used to determine how to format, filter and summarize data
Guided by knowledge, the resulting information is interpreted
– this leads to decisions and actions
Systems View (cont.)
The actions generate results. Comparison of actions and results helps
accumulate new knowledge– this improves the process of interpreting
information, making decisions and taking new actions.
The information search process
• the user’s constructive activity of finding meaning from information in order to extend his or her state of knowledge
• the process of sense-making within a personal frame of reference
The user and information-seeking behavior
• There is a long history of studying human behavior in seeking and using information
• Systems-oriented studies and information-as-object-oriented systems
• User-oriented studies and user-oriented systems
Systems orientation
• Information is viewed as: – an external objective entity – having a content-based reality – existing independently of users or social
systems.
User-centered
• Information is viewed as: – a subjective construction
– that is created internally in the minds of the users
• User orientation– Users, looking for information to aid problem
solving and decision-making, have inadequacies in their state of knowledge - gaps or uncertainties
• sometimes they know what they need to find out; sometimes they don’t
User-centered (cont.)
– Information systems should be designed to assist users in discovering and representing their knowledge of a problem situation
• User model– A general user model of information seeking
behavior must encompass both the user and his context, i,e., the information behavior of the user and the environment in which this behavior occurs.
Information Behavior
• Information needs
• Information seeking
• Information use
Dervin’s Sense-Making Model
• Dervin’s sense-making model focuses on the user’s cognitive needs– the user moves through space and time – making sense of his/her actions, the
environment and the information system’s inputs
• As long as everything is meaningful, movement ahead is possible.
Dervin’s Sense-Making Model
• But, movement ahead may be blocked by stops or cognitive gaps
• And user must define the nature of the gap or the cause of the stop
• Based on user’s assessment, he selects tactics and information to bridge the gap.
Kuhlthau’s model
• Distinguished stages in the information search and use process -each stage characterized by the user’s behavior in three realms of experience – the affective (feelings) – the cognitive (thought) – the physical (action)
Kuhlthau’s model (cont.)
• Six stages of the information search process: – initiation – selection – exploration – formulation – collection – presentation
Communication between the user and the
information retrieval system • each has its own language (concepts vs.
symbols) • user must “translate” his information need
into one the information system will understand OR
• the information system must interpret the information need of the user and translate the user’s request into one that the system can process
How is this communication accomplished?
• Different ways of searching
– controlled vocabulary
– natural language
Information ecology
• User behavior and user environments– part of what Davenport calls the “information
ecology” of an organization • internal environments and
• external environments
Information ecology (Davenport)
• Davenport views an information ecology as encompassing six components: – Information strategy – Information politics – Information behavior and culture – Information staff – Information processes (use) – Information architecture
Information Systems
• An information system is a combination of work practices, information, people, and information technology organized to accomplish goals in an organization – goals are actually outside the information
system
Forms of Information Systems
• database systems
• information storage and retrieval systems
• transaction processing systems
• management information systems
• decision support systems
• knowledge management systems
Components of information systems
• Work practices
• Information
• People
• Information technology
Information Life Cycle
• A useful way to envision information is in terms of its life cycle – the life cycle identifies the phases through
which information passes from creation to final disposition
• Life cycle phases– Creating (Authoring) – Distribution (Networking)
Information Life Cycle (cont.)
• Life cycle phases (cont.)– Use – Organizing/Indexing – Storing/Retrieving – Accessing/Retrieving – Reusing/Modifying – Disposition