Communication Theory and Semiotics

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Communication Theory and Semiotics

• Graphics 1

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Introduction

• information theory - Shannon and Weaver
• application to visual communication process
  theory
• noise redundancy, entropy
• limitations of process theory
• conclusion - process theory and semiotics .

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Warren Weaver

• American scientist and mathematician
• director of the Division of Natural Sciences at
  the Rockefeller Foundation, 1932 - 1955
• influential in the application of science
  genetics, agriculture, medicine and molecular
  engineering and many other fields
• early work on machine translation and mass
  communication - tower block analogy
• co-author with Shannon of The Mathematical Theory
  of Communication, published 1949 .

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Claude Elwood Shannon

• American mathematician and electronics engineer
• 1937, aged 21, his Masters thesis established
  mathematical basis of digital circuit design and
  hence the modern computer
• had varied interests
• created a mechanical mouse that could learn a
  maze
• invented a motorised pogo stick
• beat blackjack and roulette at casinos using game
  theory and computation
• applied his theories to the stock market and was
  very successful! .

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Shannon and Weaver, 1949

• during WW2 Shannon joined Bell Telephone Labs
• worked on fire-control systems (anti-missile
  targeting) and cryptography
• met and worked with many great scientists
• people involved with earliest satellites, signal
  theory, first digital computers, the inventors of
  the transistor
• became friends with Alan Turin, discussed
  cryptography with him
• treated the problems he encountered as the need
  to distinguish signal from noise
• by considering the role of data in contrast to
  signal processing he founded the field of
  information theory
• hence laid the foundations of all modern
  communication .

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Shannon and Weaver, 1949

• The Mathematical Theory of Communication
• based largely on the work Shannon had published
  previously
• Weaver added a philosophical context to the work,
  showing its wider applications, and used his
  influence to popularise it
• theory focuses on the best way for the sender to
  encode information before sending it
• realised that all communication, including human
  language, could be measured in the form of a rate
  of bits per second
• and that all channels of communication had
  their own maximum capacity, also measured in bits
  per second
• considered the role of noise in disrupting
  integrity of information
• limited channel capacity and noise lead to
  uncertainty
• developed the concept of information entropy
  as a measure of uncertainty in a message .

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Shannon and Weaver, 1949
Hazard warning Corrosive materials
Mandatory Wear protective clothing
Prohibited Do not touch

• what limits the capacity of the channel?
• where might noise be introduced between sender
  and receiver?

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process theory

• Shannon and Weavers contribution has been
  applied to many areas
• communications systems
• computer science
• linguistics
• cognitive science
• sociology
• media studies
• critical theory
• marketing and advertising
• if graphic design is concerned with effective
  visual communication then information theory may
  help us analyse and discuss our work process
  theory

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process theory

• all communication can be considered as a process
  in which message follows path from sender to
  receiver

source
transmitter
receiver
destination
noise
client
designer
medium
audience
noise
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communication problem levels

• Shannon and Weaver discuss three levels of
  communication problem technical, semantic,
  effectiveness
• technical level
• how accurately can we communicate the message?
• which system to use to encode the message?
• can the receiver use that system?
• semantic level
• which language to use?
• how accurately does our language convey the
  meaning we intend?
• how much can be lost whilst still preserving the
  meaning?
• effectiveness level
• does the message have the effect we want to
  achieve?
• what can we do if it doesnt? .

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communication problem levels - graphics

• addressing the technical level
• scope which information, how much, and its
  extent
• medium eg newspaper adverts, direct mail, tv and
  radio
• demographics, identifying the audience, cultural
  norms
• addressing the effectiveness level
• often considered as an ongoing aspect of the
  technical level
• previous lessons learned
• demographic information
• market research, focus groups
• relationship between technical level and
  effectiveness level can be described as
  feedback
• specification adjusted and fed back to designer
• Shannon and Weaver did not include this in their
  original work

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communication problem levels - graphics
client
designer
medium
audience
company charity government organisation agency
media producer design studio individual
print broadcast delivered signage
customer traveller / visitor
noise
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noise redundancy and entropy

• noise - anything added between sender and
  receiver
• obvious source of noise is reproduction eg
  newspaper print technical
• noise at effectiveness level comes from things
  like audience distractions, product placement,
  dimensions of signage, etc
• redundancy - repeating all or part of the message
• newspaper headlines contain little redundancy
  Child Killer Held
• redundancy can clarify the message providing
  pictogram and text
• entropy - measure of uncertainty contained in
  message
• an ambiguous message has a high entropy
• noise dilutes a message and hence increases
  entropy
• a long message does not necessarily contain a
  lot of information
• redundancy makes the message longer, but usually
  reduces ambiguity, so can reduce entropy .

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the semantic level

• Shannon and Weavers model was based in
  mathematics and communication engineering
• grounded in a field where the semantic level is
  largely predetermined
• choice of language depends on application, eg a
  human language, an electronics communication
  protocol
• accuracy of language informs choice - you
  wouldnt chose a human language for a
  fire-control system or vice versa!
• robustness of the language (and hence how much
  information can be lost without losing the
  message) are engineering constraints
• so the process model tends to treat the message
  as something to be encoded, transmitted and
  received
• does not have much to say about the message
  itself

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limitations of process models

• models like Shannon and Weavers treat
  communication as a linear process
• a message needs to be passed from A to B
• encode the message in a suitable format
• anticipate problems such as noise and
  compatibility
• build in robustness with redundancy
• analyse the result with measures such as entropy
• as a result the meaning of the message is
  determined before it leaves the sender
• process models consider minimum and maximum
  factors required to maintain integrity of the
  meaning such as
• the minimum redundancy required
• the maximum information that can be carried by a
  channel
• etc .

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process theory and semiotic theory

• as weve seen, semiotics considers the role of
  the reader when interpreting the text, eg
• red can be associated with evil or with good luck
  depending on culture
• red can mean danger and stop, or can mean romance
  and passion depending on context, within the same
  culture
• in semiotic approaches, the meaning of the
  message is fixed by the receiver, not by the
  sender!
• this takes into account noise introduced between
  sender and receiver
• also takes into account differences in culture
• also takes into account different associations in
  the same culture
• when combined, process theory and semiotics
  provide a complete framework for analysing
  effective visual communication

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Sources

• Noble, I. Bestley, R., 2007. Visual Research
  An Introduction to Research Methodologies in
  Graphic Design, AVA Publishing.  
• Crow, D., 2003. Visible Signs An Introduction to
  Semiotics, AVA Publishing.
• Baldwin, J. Roberts, L., 2006. Visual
  Communication From Theory to Practice, AVA
  Publishing.
• Chandler, D., Semiotics for Beginners,
  http//www.aber.ac.uk/media/Documents/S4B/semiotic
  .html
• http//www2.research.att.com/njas/doc/shannonbio.
  html - biography of Shannon with links to his
  papers