In a variety of contexts, exogeny or exogeneity () 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
An economy is an area of the production, distribution and trade, as well as consumption of goods and services. In general, it is defined as a social domain that emphasize the practices, discourses, and material expressions associated with the ...
model
A model is an informative representation of an object, person or system. The term originally denoted the plans of a building in late 16th-century English, and derived via French and Italian ultimately from Latin ''modulus'', a measure.
Models c ...
, 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
Economic sociology is the study of the social cause and effect of various economic phenomena. The field can be broadly divided into a classical period and a contemporary one, known as "new economic sociology".
The classical period was concerned ...
, Project IDEA (Interdisciplinary Dimensions of Economic Analysis) gave notion to understanding the exogenous factors that play a role within
economic theory
Economics () is the social science that studies the production, distribution, and consumption of goods and services.
Economics focuses on the behaviour and interactions of economic agents and how economies work. Microeconomics analyzes ...
. 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
A social class is a grouping of people into a set of hierarchical social categories, the most common being the upper, middle and lower classes. Membership in a social class can for example be dependent on education, wealth, occupation, inco ...
in populations, and preferences based on social factors of an individual.
Exogenous Factors in Econometrics
In
econometrics
Econometrics is the application of statistical methods to economic data in order to give empirical content to economic relationships. M. Hashem Pesaran (1987). "Econometrics," '' The New Palgrave: A Dictionary of Economics'', v. 2, p. 8 p. 8 ...
, an
endogenous random variable is
correlated
In statistics, correlation or dependence is any statistical relationship, whether causal or not, between two random variables or bivariate data. Although in the broadest sense, "correlation" may indicate any type of association, in statistic ...
with the
error term In mathematics and statistics, an error term is an additive type of error. Common examples include:
* errors and residuals in statistics, e.g. in linear regression
* the error term in numerical integration
In analysis, numerical integration ...
in the econometric model, while an exogenous variable is not. However, exogenous variables aid in the explanation of endogenous variable variances. In the preset group, it is typical to include historical values of endogenous variables. Exogenous variables are independent of the model's
disturbance term
In statistics, linear regression is a Linearity, linear approach for modelling the relationship between a Scalar (mathematics), scalar response and one or more explanatory variables (also known as dependent and independent variables). The case of ...
, since they are preset. They meet the same conditions as
explanatory variables do in a traditional
regression model
In statistical modeling, regression analysis is a set of statistical processes for estimating the relationships between a dependent variable (often called the 'outcome' or 'response' variable, or a 'label' in machine learning parlance) and one ...
.
Biology and Medicine
Biology
An exogenous
contrast agent
A contrast agent (or contrast medium) is a substance used to increase the contrast of structures or fluids within the body in medical imaging. Contrast agents absorb or alter external electromagnetism or ultrasound, which is different from radiop ...
, in
medical imaging for example, is a liquid injected into the patient
intravenously
Intravenous therapy (abbreviated as IV therapy) is a medical technique that administers fluids, medications and nutrients directly into a person's vein. The intravenous route of administration is commonly used for rehydration or to provide nutrie ...
that enhances visibility of a pathology, such as a
tumor
A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...
. An exogenous factor is any material that is present and active in an individual
organism
In biology, an organism () is any living system that functions as an individual entity. All organisms are composed of cells (cell theory). Organisms are classified by taxonomy into groups such as multicellular animals, plants, and ...
or living
cell
Cell most often refers to:
* Cell (biology), the functional basic unit of life
Cell may also refer to:
Locations
* Monastic cell, a small room, hut, or cave in which a religious recluse lives, alternatively the small precursor of a monastery ...
but that originated outside that organism, as opposed to an endogenous factor.
In the origins of
diseases, exogenous factors, namely those that are factors of
inflammation
Inflammation (from la, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants, and is a protective response involving immune cells, blood vessels, and molec ...
or
stress
Stress may refer to:
Science and medicine
* Stress (biology), an organism's response to a stressor such as an environmental condition
* Stress (linguistics), relative emphasis or prominence given to a syllable in a word, or to a word in a phrase ...
, such as
overexertion
Exertion is the physical or perceived use of energy.Newton's Third Law, Elert, Glenn. “Forces.” ''Viscosity – The Physics Hypertextbook'', physics.info/newton-first/. Exertion traditionally connotes a strenuous or costly ''effort'', resulting ...
,
overeating
Overeating occurs when an individual consumes more calories in relation to the energy that is expended via physical activity or expelled via excretion, leading to weight gain and often obesity. Overeating is the defining characteristic of bing ...
, and extreme feelings of emotions of grief or anger, all contribute to exhaustion or modifications in
genes. An accumulation of such stressors affect the
immune system
The immune system is a network of biological processes that protects an organism from diseases. It detects and responds to a wide variety of pathogens, from viruses to parasitic worms, as well as cancer cells and objects such as wood splint ...
by disrupting the amount of communication that occurs between the immune system and other areas of the body.
DNA introduced to cells via
transfection
Transfection is the process of deliberately introducing naked or purified nucleic acids into eukaryotic cells. It may also refer to other methods and cell types, although other terms are often preferred: " transformation" is typically used to des ...
or
viral transduction
Transduction is the process by which foreign DNA is introduced into a cell by a virus or viral vector. An example is the viral transfer of DNA from one bacterium to another and hence an example of horizontal gene transfer. Transduction does not ...
is an exogenous factor. Exogenous factors in DNA, particularly
DNA damage
DNA repair is a collection of processes by which a cell identifies and corrects damage to the DNA molecules that encode its genome. In human cells, both normal metabolic activities and environmental factors such as radiation can cause DNA d ...
, are more known as environmental factors that cause progression in the impairment of DNA. Such exogenous factors would be different chemical agents,
ionizing radiation (IR), and
ultraviolet radiation
Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiation i ...
(UV). These factors penetrate the deeper layers of the cell, causing great damage, with either
apoptosis or senescence occurring, further leading to
arrested
An arrest is the act of apprehending and taking a person into custody (legal protection or control), usually because the person has been suspected of or observed committing a crime. After being taken into custody, the person can be questi ...
or altered development and aging of the organism causing
neurological disorders
A neurological disorder is any disorder of the nervous system. Structural, biochemical or electrical abnormalities in the brain, spinal cord or other nerves can result in a range of symptoms. Examples of symptoms include paralysis, muscle weaknes ...
and
cancer
Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. These contrast with benign tumors, which do not spread. Possible signs and symptoms include a lump, abnormal b ...
.
Medicine and Medical Treatments
In
medicine
Medicine is the science and practice of caring for a patient, managing the diagnosis, prognosis, prevention, treatment, palliation of their injury or disease, and promoting their health. Medicine encompasses a variety of health care pr ...
, exogenous factors are seen in both
pathogens
In biology, a pathogen ( el, πάθος, "suffering", "passion" and , "producer of") in the oldest and broadest sense, is any organism or agent that can produce disease. A pathogen may also be referred to as an infectious agent, or simply a ger ...
and
therapeutics
A therapy or medical treatment (often abbreviated tx, Tx, or Tx) is the attempted remediation of a health problem, usually following a medical diagnosis.
As a rule, each therapy has indications and contraindications. There are many different ...
. Exogenous factors can be included in the type of
obesity
Obesity is a medical condition, sometimes considered a disease, in which excess body fat has accumulated to such an extent that it may negatively affect health. People are classified as obese when their body mass index (BMI)—a person's ...
where there is an imbalance of food and
metabolism
Metabolism (, from el, μεταβολή ''metabolē'', "change") is the set of life-sustaining chemical reactions in organisms. The three main functions of metabolism are: the conversion of the energy in food to energy available to run c ...
, 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 an imbalance of food intake itself, which include
genetic disorders
A genetic disorder is a health problem caused by one or more abnormalities in the genome. It can be caused by a mutation in a single gene (monogenic) or multiple genes (polygenic) or by a chromosomal abnormality. Although polygenic disorders ...
, interruption of
thyroid
The thyroid, or thyroid gland, is an endocrine gland in vertebrates. In humans it is in the neck and consists of two connected lobes. The lower two thirds of the lobes are connected by a thin band of tissue called the thyroid isthmus. The thy ...
functions, and other syndromic disorders.
In relation to cancer,
carcinogens
A carcinogen is any substance, radionuclide, or radiation that promotes carcinogenesis (the formation of cancer). This may be due to the ability to damage the genome or to the disruption of cellular metabolic processes. Several radioactive subs ...
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
Philosophy
In
philosophy, the origins of existence of
self
The self is an individual as the object of that individual’s own reflective consciousness. Since the ''self'' is a reference by a subject to the same subject, this reference is necessarily subjective. The sense of having a self—or ''selfhoo ...
, or the
identity
Identity may refer to:
* Identity document
* Identity (philosophy)
* Identity (social science)
* Identity (mathematics)
Arts and entertainment Film and television
* ''Identity'' (1987 film), an Iranian film
* ''Identity'' (2003 film), ...
of self, emanating from, or sustaining, outside the natural or influenced realm, are exogenous.
Psychology
Exogenous
constructivism
Constructivism may refer to:
Art and architecture
* Constructivism (art), an early 20th-century artistic movement that extols art as a practice for social purposes
* Constructivist architecture, an architectural movement in Russia in the 1920s a ...
prioritizes the reconstruction of structures that have already been created in the environment, which is based from a mechanical metaphor, and greatly reflects off of
Bandura
A bandura ( uk, банду́ра) is a Ukrainian plucked string folk instrument. It combines elements of the zither and lute and, up until the 1940s, was also often referred to by the term kobza. Early instruments (c. 1700) had 5 to 12 strings ...
's
social learning theory
Social learning is a theory of learning process social behavior which proposes that new behaviors can be acquired by observing and imitating others. It states that learning is a cognitive process that takes place in a social context and can occu ...
. Overall, exogenous constructivism is noted to assume that knowledge comes from an individual's environment, which is assumed to be learned. Because an active individual is expected to be participating in the abstraction of knowledge from its environment, practical guidance of this result of participation remains the most crucial feature of directing the learning process. The structure of the individual's operating environment has a substantial impact on the structure of the knowledge generated. Through the perspective of
Piaget Piaget () may refer to:
People with the surname
* Édouard Piaget (18171910), a Swiss entomologist
* Jean Piaget (18961980), a Swiss developmental psychologist
* Paul Piaget (disambiguation), several people
* Solange Piaget Knowles (born 1986) ...
, learning was known as the individual's former structures accommodated to those imposed by its current environment. The individual's accommodation is directed by the environment, which provides the structures to which the individual must adapt.
In attentional
psychology
Psychology is the scientific study of mind and behavior. Psychology includes the study of conscious and unconscious phenomena, including feelings and thoughts. It is an academic discipline of immense scope, crossing the boundaries between ...
, exogenous stimuli are
external stimuli without
conscious
Consciousness, at its simplest, is sentience and awareness of internal and external existence. However, the lack of definitions has led to millennia of analyses, explanations and debates by philosophers, theologians, linguisticians, and scien ...
intention. An example of this is attention drawn to a flashing light in the
periphery
Periphery or peripheral may refer to:
Music
*Periphery (band), American progressive metal band
* ''Periphery'' (album), released in 2010 by Periphery
* "Periphery", a song from Fiona Apple's album '' The Idler Wheel...''
Gaming and entertainm ...
of
vision
Vision, Visions, or The Vision may refer to:
Perception Optical perception
* Visual perception, the sense of sight
* Visual system, the physical mechanism of eyesight
* Computer vision, a field dealing with how computers can be made to gain und ...
.
Exogeny in Other Areas
Geography
In
geography
Geography (from Greek: , ''geographia''. Combination of Greek words ‘Geo’ (The Earth) and ‘Graphien’ (to describe), literally "earth description") is a field of science devoted to the study of the lands, features, inhabitants, an ...
, exogenous processes all take place outside the
Earth
Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ...
and all the other
planets.
Weathering
Weathering is the deterioration of rocks, soils and minerals as well as wood and artificial materials through contact with water, atmospheric gases, and biological organisms. Weathering occurs ''in situ'' (on site, with little or no movement) ...
,
erosion
Erosion is the action of surface processes (such as water flow or wind) that removes soil, rock, or dissolved material from one location on the Earth's crust, and then transports it to another location where it is deposited. Erosion is dis ...
, transportation and
sedimentation
Sedimentation is the deposition of sediments. It takes place when particles in suspension settle out of the fluid in which they are entrained and come to rest against a barrier. This is due to their motion through the fluid in response to the ...
are the main exogenous processes. Asides from climate, exogenous geographic factors are able to contribute to the overall process of distribution, including densities of populations and
urbanizations of certain areas in the world. Exogeneity is proposed to ultimately cause geographic considerations to be rejected.
Ludology
In
ludology
Game studies, also known as ludology (from ''ludus'', "game", and ''-logia'', "study", "research"), is the study of games, the act of playing them, and the players and cultures surrounding them. It is a field of cultural studies that deals with a ...
, the study of games, an exogenous item is anything outside the game itself. Therefore, an item in a
massively multiplayer online game
A massively multiplayer online game (MMOG or more commonly MMO) is an online video game with a large number of players, often hundreds or thousands, on the same server. MMOs usually feature a huge, persistent open world, although there are ...
would have exogenous value if people were buying it with real world money rather than
in-game currency
A virtual economy (or sometimes synthetic economy) is an emergent economy existing in a virtual world, usually exchanging virtual goods in the context of an online game, particularly in massively multiplayer online games (MMOs). People enter ...
(though its in-game cost would be
endogenous). Noted as exogenous fantasy, one may also refer to this term as extrinsic stimuli or "fantasy"; these describe a
"fantasy" (game) that solely relies on the skill being mastered, rather than the other way around. These fantasies also tend to possess a few characteristics, such as (1) understanding that the fantasy and the skill that is being learned are inextricably linked, (2) the fantasy context and the instructional content being provided have an intrinsic and continuous link, and (3) endogenous fantasies tend to include more intellectually challenging and captivating content compared to exogenous fantasies.
Materials science
In
materials science, an exogenous property of a substance is derived from outside or external influences, such as a nano-doped material.
References
External links
*{{wiktionary-inline
Etymology