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− | [[File:lighterstill.jpg]] | + | [[File:lighterstill.jpg]][[File:Riskatsea.jpg|right|frame]] |
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| '''Risk''' concerns the expected [[value]] of one or more results of one or more future [[events]]. Technically, the value of those results may be positive or negative. However, general usage tends [[focus]] only on potential harm that may arise from a future event, which may accrue either from incurring a cost ("downside risk") or by failing to attain some benefit ("upside risk"). | | '''Risk''' concerns the expected [[value]] of one or more results of one or more future [[events]]. Technically, the value of those results may be positive or negative. However, general usage tends [[focus]] only on potential harm that may arise from a future event, which may accrue either from incurring a cost ("downside risk") or by failing to attain some benefit ("upside risk"). |
| ==Historical background== | | ==Historical background== |
| The term risk may be traced back to classical [[Greek]] rizikon (Greek ριζα, riza), meaning [[radical|root]], later used in Latin for cliff. The term is used in Homer’s Rhapsody M of Odyssey "[[Dilemma|Sirens, Scylla, Charybdee]] and the bulls of Helios (Sun)" Odysseus tried to save himself from Charybdee at the cliffs of Scylla, where his ship was destroyed by heavy seas generated by Zeus as a punishment for his crew killing before the bulls of Helios (the god of the sun), by grabbing the roots of a wild fig tree. | | The term risk may be traced back to classical [[Greek]] rizikon (Greek ριζα, riza), meaning [[radical|root]], later used in Latin for cliff. The term is used in Homer’s Rhapsody M of Odyssey "[[Dilemma|Sirens, Scylla, Charybdee]] and the bulls of Helios (Sun)" Odysseus tried to save himself from Charybdee at the cliffs of Scylla, where his ship was destroyed by heavy seas generated by Zeus as a punishment for his crew killing before the bulls of Helios (the god of the sun), by grabbing the roots of a wild fig tree. |
− | | + | <center>For lessons on the [[topic]] of '''''Risk''''', follow [https://nordan.daynal.org/wiki/index.php?title=Category:Risk this link].</center> |
| For the sociologist Niklas Luhmann the term 'risk' is a neologism which appeared with the transition from traditional to modern [[society]].[1] "In the Middle Ages the term riscium was used in highly specific [[context]]s, above all sea trade and its ensuing legal problems of loss and damage."[1] In the [[vernacular]] [[language]]s of the 16th century the [[words]] rischio and riezgo were used,[1] both terms derived from the Arabic word "رزق", "rizk", meaning 'to seek [[wealth|prosperity]]'. This was introduced to continental Europe, through interaction with Middle Eastern and North African Arab traders. In the [[English]] language the term risk appeared only in the 17th century, and "seems to be imported from continental Europe."[1] When the terminology of risk took ground, it replaced the older notion that thought "in terms of good and bad fortune."[1] Niklas Luhmann (1996) seeks to explain this [[transition]]: "Perhaps, this was simply a loss of plausibility of the old [[rhetoric]]s of Fortuna as an [[allegorical]] figure of religious [[content]] and of prudentia as a (noble) [[virtue]] in the emerging commercial society."[2] | | For the sociologist Niklas Luhmann the term 'risk' is a neologism which appeared with the transition from traditional to modern [[society]].[1] "In the Middle Ages the term riscium was used in highly specific [[context]]s, above all sea trade and its ensuing legal problems of loss and damage."[1] In the [[vernacular]] [[language]]s of the 16th century the [[words]] rischio and riezgo were used,[1] both terms derived from the Arabic word "رزق", "rizk", meaning 'to seek [[wealth|prosperity]]'. This was introduced to continental Europe, through interaction with Middle Eastern and North African Arab traders. In the [[English]] language the term risk appeared only in the 17th century, and "seems to be imported from continental Europe."[1] When the terminology of risk took ground, it replaced the older notion that thought "in terms of good and bad fortune."[1] Niklas Luhmann (1996) seeks to explain this [[transition]]: "Perhaps, this was simply a loss of plausibility of the old [[rhetoric]]s of Fortuna as an [[allegorical]] figure of religious [[content]] and of prudentia as a (noble) [[virtue]] in the emerging commercial society."[2] |
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| [[File:Risk_2.jpg]] | | [[File:Risk_2.jpg]] |
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− | One of the first major uses of this [[concept]] was at the planning of the [http://en.wikipedia.org/wiki/Delta_Works Delta Works] in 1953, a flood protection program in the Netherlands, with the aid of the mathematician [http://en.wikipedia.org/wiki/David_van_Dantzig David van Dantzig].[4] The kind of risk [[analysis]] pioneered here has become common today in fields like [http://en.wikipedia.org/wiki/Nuclear_power nuclear power], [http://en.wikipedia.org/wiki/Aerospace aerospace] and [http://en.wikipedia.org/wiki/Chemical_industry chemical industry]. | + | One of the first major uses of this [[concept]] was at the planning of the [https://en.wikipedia.org/wiki/Delta_Works Delta Works] in 1953, a flood protection program in the Netherlands, with the aid of the mathematician [https://en.wikipedia.org/wiki/David_van_Dantzig David van Dantzig].[4] The kind of risk [[analysis]] pioneered here has become common today in fields like [https://en.wikipedia.org/wiki/Nuclear_power nuclear power], [https://en.wikipedia.org/wiki/Aerospace aerospace] and [https://en.wikipedia.org/wiki/Chemical_industry chemical industry]. |
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| There are more sophisticated definitions, however. [[Measuring]] [[engineering]] risk is often difficult, especially in potentially dangerous industries such as nuclear energy. Often, the [[probability]] of a negative event is estimated by using the frequency of past similar events or by event-tree methods, but probabilities for rare failures may be difficult to estimate if an event tree cannot be formulated. [[Methods]] to calculate the cost of the loss of human life vary depending on the purpose of the calculation. Specific [[method]]s include what people are willing to pay to insure against death,[5] and radiological release (e.g., GBq of radio-iodine). There are many [[formal]] [[method]]s used to assess or to "measure" risk, considered as one of the critical indicators important for human [[decision]] making. | | There are more sophisticated definitions, however. [[Measuring]] [[engineering]] risk is often difficult, especially in potentially dangerous industries such as nuclear energy. Often, the [[probability]] of a negative event is estimated by using the frequency of past similar events or by event-tree methods, but probabilities for rare failures may be difficult to estimate if an event tree cannot be formulated. [[Methods]] to calculate the cost of the loss of human life vary depending on the purpose of the calculation. Specific [[method]]s include what people are willing to pay to insure against death,[5] and radiological release (e.g., GBq of radio-iodine). There are many [[formal]] [[method]]s used to assess or to "measure" risk, considered as one of the critical indicators important for human [[decision]] making. |
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| In [[statistics]], risk is often mapped to the [[probability]] of some [[event]] which is seen as undesirable. Usually, the probability of that event and some assessment of its expected harm must be combined into a believable scenario (an outcome), which combines the set of risk, regret and reward probabilities into an expected value for that outcome. (See also Expected utility.) | | In [[statistics]], risk is often mapped to the [[probability]] of some [[event]] which is seen as undesirable. Usually, the probability of that event and some assessment of its expected harm must be combined into a believable scenario (an outcome), which combines the set of risk, regret and reward probabilities into an expected value for that outcome. (See also Expected utility.) |
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− | Thus, in [http://en.wikipedia.org/wiki/Decision_theory statistical decision theory], the risk [[function]] of an estimator δ(x) for a parameter θ, calculated from some observables x, is defined as the expectation value of the loss function L, | + | Thus, in [https://en.wikipedia.org/wiki/Decision_theory statistical decision theory], the risk [[function]] of an estimator δ(x) for a parameter θ, calculated from some observables x, is defined as the expectation value of the loss function L, |
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| [[File:Loss_function.jpg]] | | [[File:Loss_function.jpg]] |
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− | In [http://en.wikipedia.org/wiki/Information_security information security], a risk is written as an asset, the threats to the asset and the vulnerability that can be exploited by the threats to impact the asset - an example being: Our desktop computers (asset) can be compromised by malware (threat) entering the environment as an email attachment (vulnerability). | + | In [https://en.wikipedia.org/wiki/Information_security information security], a risk is written as an asset, the threats to the asset and the vulnerability that can be exploited by the threats to impact the asset - an example being: Our desktop computers (asset) can be compromised by malware (threat) entering the environment as an email attachment (vulnerability). |
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| The risk is then assessed as a function of three variables: | | The risk is then assessed as a function of three variables: |
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| The two probabilities are sometimes combined and are also known as likelihood. If any of these variables approaches zero, the overall risk approaches zero. | | The two probabilities are sometimes combined and are also known as likelihood. If any of these variables approaches zero, the overall risk approaches zero. |
− | The management of actuarial risk is called [http://en.wikipedia.org/wiki/Risk_management risk management].[http://en.wikipedia.org/wiki/Risk] | + | The management of actuarial risk is called [https://en.wikipedia.org/wiki/Risk_management risk management].[https://en.wikipedia.org/wiki/Risk] |
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| [[Category: Statistics]] | | [[Category: Statistics]] |