Inf-phen - School of Communication and Information

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Nov 30, 2013 (3 years and 7 months ago)

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© Tefko Saracevic

1

The phenomenon of
INFORMATION

Nature and multifaceted
characteristics


Tefko Saracevic

Rutgers University

© Tefko Saracevic

2

What is information?


We don’t know!!


But: What is energy, matter,
gravity, life, intelligence
...

?


All
-

information included
-

are
basic phenomena


How to study them?

All studied in terms of:



MANIFESTATIONS



BEHAVIOR



EFFECTS

© Tefko Saracevic

3

Dictionary (Oxford)

INFORM:


to form
(the mind...) esp. by
imparting, learning,
instruction


to impart
knowledge of some
fact or occurrence; to tell
(one) something

INFORMATION:


the action
of informing; the
action of telling or ... being
told of something


that of which one is
apprised
or told
; intelligence, news


© Tefko Saracevic

4

Interpretations

Information:


a complex phenomenon


spectrum of views; variety of
interpretations in differing
contexts


research in many fields from
philosophy to neuroscience


complex relation to other
phenomena e.g.
knowledge
& processes e.g.
communication


strong intuitive & context
-

dependent understanding

© Tefko Saracevic

5

Views of information:

polarization
-

spectrum

One end:

Exists in
structure of
material world
--

would be there if
we exist or not




Inf. as a

basic
phenomenon in
universe
as
energy & matter



Inf. as a basic
aspect of
living
systems

“Life is a knowledge
process” Miller


Other end:

Material world
can only
become inf.
when acted
upon by a
knower




Inf. as a
cognitive

phenomenon
only



Related to

(&
restricted to)
cognitive
processes

© Tefko Saracevic

6

Relations:

increase in
complexity of cognitive
processing

Data


Information


Knowledge


Wisdom/
insight





Symbols with
some meaning


Conversion,
interpretation


Integration,
embedding in
private &
public


Connections,
higher
interpretations

© Tefko Saracevic

7

“Information journey”

From
Data

to
Information
to
Knowledge
to
Wisdom/insight


Increased complexity
requiring cognitive skills, past
intellectual history,
intelligence
...


Processing into
new
patterns, relationships



Under contextual and
cultural dependency


Interplay between private
and public knowledge
-

RECORDS

© Tefko Saracevic

8

Scholarly treatment
-

theories of information


Variety of theories, reflecting


different points of view,
departure


different focus & restrictions on
given

characteristics


Restrictions
provide
framework for theory,
interpretation
...


Common approach in science


Any restriction, interpretation
has limitations, critics


No comprehensive theory yet


But knowledge on behavior,
effects advancing

© Tefko Saracevic

9

Theories ... characteristic,
restriction emphasized


Uncertainty

-

inf. theory


concentration on probability of
signals


link to entropy
(Shanon)


Uncertainty
-

psychology


contemplated actions

(Rapaport)


Uncertainty
-

inf. science


effects of processing
(Hayes)


Truth
-

logic, philosophy


propositions
(Belknap & Anderson)


sentences
(Fox)


Meaning
-

semantics, logic


Texts and contexts
(Bar
-
Hillel &
Carnap)

© Tefko Saracevic

10

Theories ...


Effectuation, feedback
-

cybernetics


role in communication
(Wiener)


Propagation
-

epidemic theory
of communication


changes in population
(Goffman)


Changes in mind
-

inf. science


effect on structure
(Shreider,
Belkin)


Changes in knowledge
-

inf.
science


effect on knowledge
(Brooks)


Decision making
-

management


role in process
(Yovits)


© Tefko Saracevic

11

Information: mind & brain

Cartesian dilemma


Descart: rational mind & physical
brain


Cognitive science
-

mind


Neurophysiology
-

brain


Convergence: how does brain
process information?


Theory of consciousness:


distributive memory,
interacting systems


regions in brain where
concepts are stored &
processed


brain as an “indexer organizing
inf. into categories”

© Tefko Saracevic

12

Characteristics of the notion
in information science

1. Part of human cognition

2. Has a meaning, content

3. Produced by a generator

4. Recorded, any medium

5. Represented , value
-
added

6. In context of communication

7. Basis for social interaction

8. Requested, needed; retrieved

9. Effects the recipient (user)

10. A process
-

transformation
...

11.
A thing, commodity; has value


(After Belkin, Buckland)

© Tefko Saracevic

13

Inf. as a PROCESS

Information is:


Expandable


addition, change over time



Compressible


represented, integrated
...



Transportable


various media, speeds


Diffusive


among populations; “leaks”



Shareable


repeated use by many

Inf. systems use these
attributes

© Tefko Saracevic

14

Inf. in inf. science ...


Information treated as with
these characteristics


Each subject of research,
models, experimentation


Basis for operations in inf.
systems, inf. industry


Each related to professional
practice, education


Technology applied to a
number


But: at times some treated in
isolation, as if others don’t
exist
-

a dangerous mistake

© Tefko Saracevic

15

Inf. in information science
(cont.)

Again: intuitively well understood,
but formally not well stated


Several viewpoints, models
emerged


Shannon
:

source
-
channel
-
destination


signals not content


not really
applicable


Cognitive:

changes in cognitive
structures


content processing & effects


Social:

context, situation


information seeking, tasks

© Tefko Saracevic

16

Shannon's information
theory


Developed a general model
for communication systems,
and a set of theoretical tools
for analyzing such systems,
by measuring information in
terms of probabilities
(numbers)

© Tefko Saracevic

17

Shannon … uncertainty


Defined information in terms of
probabilities


developed measure of the
information we get from
observing the occurrence of an
event, BUT ignored any
particular features of the event

»
e.g. flipping a fair coin once will
give us events h and t each with
probability 1/2, and thus a single
flip of a coin gives us
-

log
2
(1/2) =
1
bit

(
B
inary dig
it)
of information
(whether it comes up h or t)


Information measured in bits is
the reduction in uncertainty in
the mind of the receiver


information (in bits) is the amount
of uncertainty a measure eliminates



© Tefko Saracevic

18

Shannon’s impact


Had great impact in treating
of digital information as
signals


e.g maximizing capacities of
channels; coding


Had disappointing impact
(despite many tries) where
information is connected with
meaning, context, humans,
values


the ideal to measure
information in human terms is
elusive


but keep trying …

© Tefko Saracevic

19

Cognitive


basic idea:

K(S) +
Δ
I = K(S +
Δ
S)

(
Brookes)



Information

when operating on a
knowledge structure

produces an
effect whereby the knowledge
structure is
changed


“Information is differences that
make a difference”
(find who said it!)


Actually, it only states the
problem




“unoperational” in information systems


involves cognitive, mental events only


constructivists rejected it

© Tefko Saracevic

20

Inf. manifestations
(Buckland)


Information as a
process


what someone knows is changed
when informed; “the action of
informing” (similar as Brookes)

»
refers to cognitive changes +
process of doing it


Information as
knowledge


knowledge communicated about x

»
uncertainty removal a special
case

»
refers to that which is being
communicated
-

intangible


Information as a
thing


data, documents with quality of
imparting information
-

tangible

»
refers to potential information
conveyed from objects


© Tefko Saracevic

21

Three senses (from narrowest to broadest)

1.
Information in terms of decision
involving little or no cognitive
processing
-

Shannon


signals, bits, straightforward data
-

computing,
telecommunication, economics,

2.
Information involving cognitive
processing & understanding
-

Brookes


understanding, matching texts

3.
Information also as related to
context, situation, problem
-
at
-
hand,
process


Buckland to some extend


users, use, tasks

For information science (including information
retrieval):


third, broadest interpretation
necessary

Senses of inf. in inf. science

© Tefko Saracevic

22

What is in a book?



for discussion in class

© Tefko Saracevic

23

Cover
page of
a book:


What is
in it?


© Tefko Saracevic

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A
chapter
in that
book

© Tefko Saracevic

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Here
is
also a
cover
page
of a
book
:


What is
in it?


© Tefko Saracevic

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A
chapte
r in
that
book

© Tefko Saracevic

27

Adequacy?


None of the theories about
information are adequate to
cover fully information as a
phenomenon


Each covers a bit or simply
describes manifestation


Shannon’s theory is testable,
but reduces “information” to
signals only


A scientific theory is one that
can be refuted


tested for
confirmation, rejection
(
Popper)

© Tefko Saracevic

28

Conclusions


Inf.
-

a complex phenomenon
but with recognizable &
definable properties


Researched in many fields,
from many angles


communication not good


Attributes used in many
applications & inf. systems


often with intuitive
understanding of properties


Slow convergence of ideas


Work on information of
increasing importance
-

social dimensions

© Tefko Saracevic

29

So we went to study


Human information behavior


“how people need, seek,
manage, give, and use
information in different contexts”
(Pettigrew )


many models, theories, studies
on a variety of aspects


extends to study of web behavior


Bibliometrics



the study, or measurement, of
texts and information”
(Norton)



many studies and formal
statements about structure &
patterns of literatures, citations,
authors, journals, texts …


Bradford’s law, Lotka’s law

© Tefko Saracevic

30

to be continued …


We cover these in other lectures
and courses


and two 2005 books cover very
nicely the topics of



theories of human information
behavior

and




integration of information
seeking and information retrieval
in context


highly recommended

© Tefko Saracevic

31

© Tefko Saracevic

32