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Systems Theory/Inputs-Outputs

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Inputs and OutputsEdit

Input is something put into a system or expended in its operation to achieve output or a result. The information entered into a computer system, examples include: typed text, mouse clicks, etc. Output is the information produced by a system or process from a specific input. Within the context of systems theory, the inputs are what are put into a system and the outputs are the results obtained after running an entire process or just a small part of a process. Because the outputs can be the results of an individual unit of a larger process, outputs of one part of a process can be the inputs to another part of the process. Output includes the visual, auditory, or tactile perceptions provided by the computer after processing the provided information. Examples include: text, images, sound, or video displayed on a monitor or through speaker as well as text or Braille from printers or embossers.

Input-Output AnalysisEdit

Input-output analysis is “a technique used in economics for tracing resources and products within an economy. The system of producers and consumers is divided into different branches, which are defined in terms of the resources they require as inputs and what they produce as outputs. The quantities of input and output for a given time period, usually expressed in monetary terms, are entered into an input-output matrix within which one can analyze what happens within and across various sectors of an economy where growth and decline takes place and what effects various subsidies may have” (Krippendorf).

Areas of ConsiderationEdit

Systems theory is “transdisciplinary study of the abstract organization of phenomena, independent of their substance, type, or spatial or temporal scale of existence” (Universiteit). It can be applied to general systems that exist in nature or, in a business context, organizational or economic systems. In studying systems theory, there are a few common, major aspects to consider.

One must look at the individual objects that compose a system. The objects consist of the parts, elements, or variables that make up the system. The objects that make up a system can be physical objects that actually exist in the world, or they can be abstract objects or ideas that cannot be found physically in the world.

One must also consider the attributes of a system. The attributes consist of the qualities and properties of the aforementioned objects of the system. The attributes may also describe the entire system itself.

A third consideration would be the internal relationships among the objects of a system.

The fourth consideration would be the environment in which the system exists.

All of these aspects of a system play an important role. Using these four characteristics, a system can then be defined as “a set of things that affect one another within an environment and form a larger pattern that is different from any of the parts.” Furthermore, “The fundamental systems-interactive paradigm of organizational analysis features the continual stages of input, throughput (processing), and output, which demonstrate the concept of openness/closedness” (Universiteit).

Systems DefinedEdit

A system can be defined by using the definition of desired outputs to understand what inputs are necessary. The following questions can be used for this method:

  1. What essential outputs must the system produce in order to satisfy the system users’ requirements?
  2. What transformations are necessary to produce these outputs?
  3. What inputs are necessary for these transformations to produce the desired outputs?
  4. What types of information does the system need to retain?

Another way of defining a system is to work forward in a stimulus-response method of definition. The following questions can be asked in conjunction with this method in order to define the system:

  1. What are the stimuli, and what are the responses to each stimulus?
  2. For each stimulus response pair, what are the transformations necessary?
  3. What are the essential data that must be maintained?

These methods can be used to define not just the general system in question, but also the subsystems which compose the larger system as a whole (Sauter).


Krippendorf (Accessed 2005): "Input-Output Analysis", in: F. Heylighen, C. Joslyn and V. Turchin (editors): Principia Cybernetica Web (Principia Cybernetica, Brussels), URL:

Universiteit Twente de ondernemende universiteit (Accessed 2005): “System Theory”. URL:

Sauter, Vicki L. (Accessed 2005): “Systems Theory”. Last Modified: 2000. URL: ggg4ye[--te' /'vn-5hh5te5 6q46yg} \[nHHGH4