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Information

2007 Schools Wikipedia Selection. Related subjects: Everyday life;
Mathematics

   The word, "Wikipedia", in binary, the form most commonly used for
   storing computer information.
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   The word, "Wikipedia", in binary, the form most commonly used for
   storing computer information.

   Information is the result of processing, manipulating and organizing
   data in a way that adds to the knowledge of the person receiving it.

   Information as a concept bears a diversity of meanings, from everyday
   usage to technical settings. Generally speaking, the concept of
   information is closely related to notions of constraint, communication,
   control, data, form, instruction, knowledge, meaning, mental stimulus,
   pattern, perception, and representation.

   Many people speak about the Information Age as the advent of the
   Knowledge Age or knowledge society, the information society, and
   information technologies, and even though informatics, information
   science and computer science are often in the spotlight, the word
   "information" is often used without careful consideration of the
   various meanings it has acquired.

Information as a message

   Information is the state of a system of interest (curiosity). Message
   is the information materialized.

   Information is a quality of a message a sender to one or more
   receivers. Information is always about something (size of a parameter,
   occurrence of an event, ...). Viewed in this manner, information does
   not have to be accurate. It may be a truth or a lie, or just the sound
   of a kiss. Even a disruptive noise used to inhibit the flow of
   communication and create misunderstanding would in this view be a form
   of information. However, generally speaking, if the amount of
   information in the received message increases the more accurate the
   message is.

   This model assumes there is a definite sender and at least one
   receiver. Many refinements of the model assume the existence of a
   common language understood by the sender and at least one of the
   receivers. An important variation identifies information as that which
   would be communicated by a message if it were sent from a sender to a
   receiver capable of understanding the message. However, in requiring
   the existence of a definite sender, the "information as a message"
   model does not attach any significance to the idea that information is
   something that can be extracted from an environment, e.g., through
   observation, reading or measurement.

   Information is a term with many meanings depending on context, but is
   as a rule closely related to such concepts as meaning, knowledge,
   instruction, communication, representation, and mental stimulus. Simply
   stated, Information is a message received and understood. In terms of
   data, it can be defined as a collection of facts from which conclusions
   may be drawn. There are many other aspects of information since it is
   the knowledge acquired through study or experience or instruction. But
   overall, information is the result of processing, manipulating and
   organizing data in a way that adds to the knowledge of the person
   receiving it.

   Communication theory is a numerical measure of the uncertainty of an
   outcome, for example, we can say that "the signal contained thousands
   of bits of information". Communication theory tends to use the concept
   of information entropy, generally attributed to C.E. Shannon (see
   below).

   Another form of information is the Fisher information, a concept of
   R.A. Fisher. This is used in application of statistics to estimation
   theory and to science in general. Fisher information is thought of as
   the amount of information that a message carries about an unobservable
   parameter. It can be computed from knowledge of the likelihood function
   defining the system. For example, with a normal likelihood function,
   the Fisher information is the reciprocal of the variance of the law. In
   the absence of knowledge of the likelihood law, the Fisher information
   may be computed from normally distributed score data as the reciprocal
   of their second moment.

   Even though information and data are often used interchangeably, they
   are actually very different. Data is a set of unrelated information,
   and as such is of no use until it is properly evaluated. Upon
   evaluation, once there is some significant relation between data, and
   they show some relevance, then it is converted into information. Now
   this same data can be used for different purposes. Thus, till the data
   convey some information, they are not useful.

Measuring information entropy

   The view of information as a message came into prominence with the
   publication in 1948 of an influential paper by Claude Shannon, " A
   Mathematical Theory of Communication." This paper provides the
   foundations of information theory and endows the word information not
   only with a technical meaning but also a measure. If the sending device
   is equally likely to send any one of a set of N messages, then the
   preferred measure of "the information produced when one message is
   chosen from the set" is the base two logarithm of N (This measure is
   called self-information). In this paper, Shannon continues:

          The choice of a logarithmic base corresponds to the choice of a
          unit for measuring information. If the base 2 is used the
          resulting units may be called binary digits, or more briefly
          bits, a word suggested by J. W. Tukey. A device with two stable
          positions, such as a relay or a flip-flop circuit, can store one
          bit of information. N such devices can store N bits... [The Bell
          System Technical Journal, Vol. 27, p. 379, (July 1948).]

   A complementary way of measuring information is provided by Algorithmic
   information theory. In brief, this measures the information content of
   a list of symbols based on how predictable they are, or more
   specifically how easy it is to generate the list. The sequence below
   would have a very low algorithmic information measurement since it is a
   very predictable pattern, and as the pattern continues the measurement
   would not change. Shannon information would give the same information
   measurement for each symbol, since they are statistically random, and
   each new symbol would increase the measurement.

          123456789101112131415161718192021

   It is important to recognise the limitations of Shannon's work from the
   perspective of human meaning. When referring to the meaning content of
   a message Shannon noted “Frequently the messages have meaning… these
   semantic aspects of communication are irrelevant to the engineering
   problem. The significant aspect is that the actual message is one
   selected from a set of possible messages” (emphasis in original).

   In Information Theory signals are part of a process, not a substance,
   they do something, they do not contain any specific meaning. Combining
   Algorithmic information theory and Information Theory we can conclude
   that the most random signal contains the most information as it can be
   interpreted in any way and cannot be compressed.

   Micheal Reddy noted that “signals” of the mathematical theory are
   “patterns that can be exchanged”. There is no message contained in the
   signal, the signals covey the ability to select from a set of possible
   messages.” In information theory “the system must be designed to
   operate for each possible selection, not just the one which will
   actually be chosen since this is unknown at the time of design.

Information as a pattern

   Information is any represented pattern. This view assumes neither
   accuracy nor directly communicating parties, but instead assumes a
   separation between an object and its representation, as well as the
   involvement of someone capable of understanding this relationship. This
   view seems therefore to require a conscious mind. Consider the
   following example: economic statistics represent an economy, however
   inaccurately. What are commonly referred to as data in computing,
   statistics, and other fields, are forms of information in this sense.
   The electro-magnetic patterns in a computer network and connected
   devices are related to something other than the pattern itself, such as
   text to be displayed and keyboard input. Signals, signs, and symbols
   are also in this category. On the other hand, according to semiotics,
   data is symbols with certain syntax and information is data with a
   certain semantic. Painting and drawing contain information to the
   extent that they represent something such as an assortment of objects
   on a table, a profile, or a landscape. In other words, when a pattern
   of something is transposed to a pattern of something else, the latter
   is information. This type of information still assumes some involvement
   of conscious mind, of either the entity constructing the
   representation, or the entity interpreting it.

   If you accept that information can be defined merely as a pattern, does
   it not follow that neither utility nor meaning are necessary components
   of information? Surely a distinction must be made between raw
   unprocessed data and information which possesses utility, value or some
   quantum of meaning. Information may indeed be characterised as a
   pattern; it is a necessary condition, but not sufficient. For example a
   telephone book follows a specific pattern: name, address, telephone
   number.

   An individual entry does not become "informative" in some sense unless
   and until it possesses some degree of utility, value or meaning. For
   example, someone might look up a girlfriend's number, might order a
   take away etc. The vast majority of numbers will never be construed as
   "information" in any meaningful sense. The gap between data and
   information is only closed by a behavioural bridge whereby some value,
   utility or meaning is added to transform mere data or pattern into
   information.

   When one constructs a representation of an object, one can selectively
   extract from the object ( sampling) or use a system of signs to replace
   ( encoding), or both. The sampling and encoding result in
   representation. An example of the former is a "sample" of a product; an
   example of the latter is "verbal description" of a product. Both
   contain information of the product, however inaccurate. When one
   interprets representation, one can predict a broader pattern from a
   limited number of observations (inference) or understand the relation
   between patterns of two different things ( decoding). One example of
   the former is to sip a soup to know if it is spoiled; an example of the
   latter is examining footprints to determine the animal and its
   condition. In both cases, information sources are not constructed or
   presented by some "sender" of information. To repeat, information in
   this sense does not assume direct communication, but it assumes
   involvement of some conscious mind.

   Regardless, information is dependent upon, but usually unrelated to and
   separate from, the medium or media used to express it. In other words,
   the position of a theoretical series of bits, or even the output once
   interpreted by a computer or similar device, is unimportant, except
   when someone or something is present to interpret the information.
   Therefore, a quantity of information is totally distinct from its
   medium.

Information as sensory input

   Often information is viewed as a type of input to an organism or
   designed device. Inputs are of two kinds. Some inputs are important to
   the function of the organism (for example, food) or device (energy) by
   themselves. In his book Sensory Ecology, Dusenbery called these causal
   inputs. Other inputs (information) are important only because they are
   associated with causal inputs and can be used to predict the occurrence
   of a causal input at a later time (and perhaps another place). Some
   information is important because of association with other information
   but eventually there must be a connection to a causal input. In
   practice, information is usually carried by weak stimuli that must be
   detected by specialized sensory systems and amplified by energy inputs
   before they can be functional to the organism or device. For example,
   light is often a causal input to plants but provides information to
   animals. The colored light reflected from a flower is too weak to do
   much photosynthetic work but the visual system of the bee detects it
   and the bee's nervous system uses the information to guide the bee to
   the flower, where the bee often finds nectar or pollen, which are
   causal inputs, serving a nutritional function.

   Information is any type of sensory input. When an organism with a
   nervous system receives an input, it transforms the input into an
   electrical signal. This is regarded information by some. The idea of
   representation is still relevant, but in a slightly different manner.
   That is, while abstract painting does not represent anything
   concretely, when the viewer sees the painting, it is nevertheless
   transformed into electrical signals that create a representation of the
   painting. Defined this way, information does not have to be related to
   truth, communication, or representation of an object. Entertainment in
   general is not intended to be informative. Music, the performing arts,
   amusement parks, works of fiction and so on are thus forms of
   information in this sense, but they are not forms of information
   according to the previous definitions above. Consider another example:
   food supplies both nutrition and taste for those who eat it. If
   information is equated to sensory input, then nutrition is not
   information but taste is.

Information as an influence which leads to a transformation

   Information is any type of pattern that influences the formation or
   transformation of other patterns. In this sense, there is no need for a
   conscious mind to perceive, much less appreciate, the pattern.
   Consider, for example, DNA. The sequence of nucleotides is a pattern
   that influences the formation and development of an organism without
   any need for a conscious mind. Systems theory at times seems to refer
   to information in this sense, assuming information does not necessarily
   involve any conscious mind, and patterns circulating (due to feedback)
   in the system can be called information. In other words, it can be said
   that information in this sense is something potentially perceived as
   representation, though not created or presented for that purpose.

   When Marshall McLuhan speaks of media and their effects on human
   cultures, he refers to the structure of artifacts that in turn shape
   our behaviors and mindsets. Also, pheromones are often said to be
   "information" in this sense.

   In 2003, J. D. Bekenstein claimed there is a growing trend in physics
   to define the physical world as being made of information itself (and
   thus information is defined in this way).

   See the section below on information as a property in physics. (Also
   see Gregory Bateson.)

Information as a property in physics

   Information has a well defined meaning in physics. Examples of this
   include the phenomenon of quantum entanglement where particles can
   interact without reference to their separation or the speed of light.
   Information itself cannot travel faster than light even if the
   information is transmitted indirectly. This could lead to the fact that
   all attempts at physically observing a particle with an "entangled"
   relationship to another are slowed down, even though the particles are
   not connected in any other way other than by the information they
   carry.

   Another link is demonstrated by the Maxwell's demon thought experiment.
   In this experiment, a direct relationship between information and
   another physical property, entropy, is demonstrated. A consequence is
   that it is impossible to destroy information without increasing the
   entropy of a system; in practical terms this often means generating
   heat. Thus, in the study of logic gates, the theoretical lower bound of
   thermal energy released by an AND gate is more than for the NOT gate
   (because information is destroyed in an AND gate and simply converted
   in a NOT gate). Physical information is of particular importance in the
   theory of quantum computers.

Etymology

   According to the Oxford English Dictionary, the earliest historical
   meaning of the word information in English was the act of informing, or
   giving form or shape to the mind, as in education, instruction, or
   training. A quote from 1387: "Five books come down from heaven for
   information of mankind." It was also used for an item of training, e.g.
   a particular instruction. "Melibee had heard the great skills and
   reasons of Dame Prudence, and her wise informations and techniques."
   (1386)

   The English word was apparently derived by adding the common "noun of
   action" ending "-ation" (descended through French from Latin "-tio") to
   the earlier verb to inform, in the sense of to give form to the mind,
   to discipline, instruct, teach: "Men so wise should go and inform their
   kings." (1330) Inform itself comes (via French) from the Latin verb
   informare, to give form to, to form an idea of. Furthermore, Latin
   itself already even contained the word informatio meaning concept or
   idea, but the extent to which this may have influenced the development
   of the word information in English is unclear.

   As a final note, the ancient Greek word for form was eidos, and this
   word was famously used in a technical philosophical sense by Plato (and
   later Aristotle) to denote the ideal identity or essence of something
   (see The Forms).

Information and Data

   The words, information and data, are used interchangeably in many
   contexts. However, they are not synonyms. For example, according to
   Adam M. Gadomski's observation (1993), data are everything what is/can
   be processed and information are data which describe a physical or
   abstract domain.

Information as Records

   Records are a specialized form of information. Essentially records are
   information produced as by-products of business activities or
   transactions or consciously as a record of such activities or
   transactions and retained because of their value. Primarily the value
   is as evidence of the activities of the organization but they may also
   be retained for their informational value. Sound Records management
   ensures that the integrity of records is preserved for as long as they
   are required.

   The international standard on Records management, ISO 15489, defines
   records as "information created, received, and maintained as evidence
   and information by an organization or person, in pursuance of legal
   obligations or in the transaction of business". The International
   Committee on Archives (ICA) Committee on electronic records defined a
   record as, "a specific piece of recorded information generated,
   collected or received in the initiation, conduct or completion of an
   activity and that comprises sufficient content, context and structure
   to provide proof or evidence of that activity".

   Records may be retained because of their business value, as part of the
   Corporate memory of the organization or to meet legal, fiscal or
   accountability requirements imposed on the organization. Willis (2005)
   expressed the view that sound management of business records and
   information delivered “…six key requirements for good Corporate
   governance … transparency; accountability; due process; compliance;
   meeting statutory and common law requirements; and security of personal
   and corporate information.
   Retrieved from " http://en.wikipedia.org/wiki/Information"
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   with only minor checks and changes (see www.wikipedia.org for details
   of authors and sources) and is available under the GNU Free
   Documentation License. See also our Disclaimer.
