info
Hello and welcome to the information page. One day I will actually write some information here but when that day will come is anyones guess, so until then:
Dyadic Sea: The modern world wonder commonly known as the internet.
Dyadica: A little outpost at the edge of the dyadic sea.
Information is the state of a system of interest. Message is the information materialized.
Information is a quality of a message from a sender to one or more receivers. Information is always about something (size of a parameter, occurrence of an event, etc). 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 falling tree. 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 message is more accurate.
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 provides 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 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 they are converted into information. Now this same data can be used for different purposes. Thus, till the data convey some information, they are not useful.
