User:Anxii/Exogeny

Exogeny
In a variety of contexts, exogeny or exogeneity (from Greek ἔξω éxō 'outside' and -γένεια -géneia 'to produce') is the fact of an action or object originating externally. It contrasts with endogeneity or endogeny, the fact of being influenced within a system.

Economics
In an economic model, an exogenous change is one that comes from outside the model and is unexplained by the model. Such changes of an economic model from outside factors can include the influence of technology, in which this had previously been noted as an exogenous factor, but has rather been noted as a factor that can depict economic forces as a whole. In economic sociology, Project IDEA (Interdisciplinary Dimensions of Economic Analysis) gave notion to understanding the exogenous factors that play a role within economic theory. Developed from the International Social Science Council (ISSC) in the year of 1982, Project IDEA was founded to gather ideas from economists and sociologists in order to conceptualize what economic sociology incorporates, as they have sought to understand why these two fields have been estranged from each other. Such exogenous factors in economic theory include laws placed in economic systems by governments, ranks of social classes in populations, and preferences based on social factors of an individual.

In econometrics, an endogenous random variable is correlated with the error term in the econometric model, while an exogenous variable is not.

Biology
In biology, an exogenous contrast agent in medical imaging for example, is a liquid injected into the patient intravenously that enhances visibility of a pathology, such as a tumor. An exogenous factor is any material that is present and active in an individual organism or living cell but that originated outside that organism, as opposed to an endogenous factor.

In medicine, exogenous factors are seen in both pathogens and therapeutics. Further in the medical aspect, exogenous factors can be included in obesity, referring to the type of obesity where there is an imbalance of food and metabolism, in which one consumes a much greater amount than the human body can handle. On the opposite end, endogenous obesity refers to obesity caused by disorders or issues outside of an imbalance of food take itself, which include genetic disorders, interruption of thyroid functions, and other syndromic disorders.


 * DNA introduced to cells via transfection or viral transduction is an exogenous factor.
 * Carcinogens are exogenous factors, in which these are made up of various factors (chemical, biological, physical), causing cancer after having entering through several routes of the body.

Social Sciences

 * In philosophy, the origins of existence of self, or the identity of self, emanating from, or sustaining, outside the natural or influenced realm, are exogenous.


 * In attentional psychology, exogenous stimuli are external stimuli without conscious intention. An example of this is attention drawn to a flashing light in the periphery of vision.

Exogeny in Other Areas

 * In geography, exogenous processes all take place outside the Earth and all the other planets. Weathering, erosion, transportation and sedimentation are the main exogenous processes.
 * In ludology, the study of games, an exogenous item is anything outside the game itself. Therefore, an item in a massively multiplayer online game would have exogenous value if people were buying it with real world money rather than in-game currency (though its in-game cost would be endogenous).
 * In materials science, an exogenous property of a substance is derived from outside or external influences, such as a nano-doped material.