Definitionsofrisk.docx

Definitionsofrisk.docx

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Definitionsofrisk

Definitionsofrisk

1.Definitionsofrisk1

Historicalbackground3

Riskversusuncertainty4

2.Insuranceandhealthrisk5

3.Economicrisk5

Insight5

Inbusiness6

Criticism6

Risk-sensitiveindustries6

Infinance7

Inpublicworks8

InHumanServices9

4.Riskinpsychology9

Regret9

Framing9

Fearasintuitiveriskassessment10

5.Rootcausesofrisk10

6.Riskassessmentandmanagement11

7.Riskinauditing11

8.Categoriesofrisks11

9.References12

Notes12

Bibliography12

Articlesandpapers13

Magazinesandjournals14

Societies14

Riskisaconceptthatdenotesapotentialnegativeimpacttosomecharacteristicofvaluethatmayarisefromafutureevent,orwecansaythat"Risksareeventsorconditionsthatmayoccur,andwhoseoccurrence,ifitdoestakeplace,hasaharmfulornegativeeffect".Exposuretotheconsequencesofuncertaintyconstitutesarisk.Ineverydayusage,riskisoftenusedsynonymouslywiththeprobabilityofaknownloss.

Riskcommunicationandriskperceptionareessentialfactorsforallhumandecisionmaking.

1.Definitionsofrisk

Therearemanydefinitionsofriskthatvarybyspecificapplicationandsituationalcontext.Oneisthatriskisanissue（事件）,whichcanbeavoidedormitigated（whereinanissueisapotentialproblemthathastobefixednow.）Riskisdescribedbothqualitativelyandquantitatively.Insometextsriskisdescribedasasituation（状况）whichwouldleadtonegativeconsequences.

Qualitatively,riskisproportionaltoboththeexpectedlosseswhichmaybecausedbyaneventandtotheprobabilityofthisevent.Greaterlossandgreatereventlikelihoodresultinagreateroverallrisk.

Frequentlyinthesubjectmatterliterature（专业文献）,riskisdefinedinpseudo-formalformswherethecomponentsofthedefinitionarevague（不明确）andill-defined（不清楚）,forexample,riskisconsideredasanindicatorofthreat,ordependsonthreats,vulnerability（易损性）,impactanduncertainty.

Inengineering,thedefinitionriskoftensimplyis:

Orinmoregeneralterms:

Therearemoresophisticateddefinitions,however.Measuringengineeringriskisoftendifficult,especiallyinpotentiallydangerousindustriessuchasnuclearenergy.Often,theprobability（概率）ofanegativeeventisestimatedbyusingthefrequency（频率）ofpastsimilareventsorbyevent-tree（事故树）methods,butprobabilitiesforrarefailuresmaybedifficulttoestimateifaneventtreecannotbeformulated.Methodstocalculatethecostofthelossofhumanlifevarydependingonthepurposeofthecalculation.Specificmethodsincludewhatpeoplearewillingtopaytoinsureagainstdeath[1],andradiologicalrelease（e.g.,GBqofradio-iodine）.Therearemanyformalmethodsusedtoassessorto"measure"risk,consideredasoneofthecriticalindicatorsimportantforhumandecisionmaking.

Financialriskisoftendefinedastheunexpectedvariabilityorvolatility（波动）ofreturnsandthusincludesbothpotentialworse-than-expectedaswellasbetter-than-expectedreturns（预期以外的损失和收益）.Referencestonegativeriskbelowshouldbereadasapplyingtopositiveimpactsoropportunity（e.g.,for"loss"read"lossorgain"）unlessthecontextprecludes.

Instatistics,riskisoftenmappedtotheprobabilityofsomeeventwhichisseenasundesirable.Usually,theprobabilityofthateventandsomeassessmentofitsexpectedharmmustbecombinedintoabelievablescenario（anoutcome）,whichcombinesthesetofrisk,regretandrewardprobabilitiesintoanexpectedvalueforthatoutcome.

Thus,instatisticaldecisiontheory,theriskfunctionofanestimatorδ（x）foraparameterθ,calculatedfromsomeobservablesx,isdefinedastheexpectationvalueofthelossfunctionL,

Ininformationsecurity,ariskisdefinedasafunctionofthreevariables:

1.theprobabilitythatthereisathreat

2.theprobabilitythatthereareanyvulnerabilities（不安全因素）

3.thepotentialimpact（潜在影响）.

Ifanyofthesevariablesapproacheszero,theoverallriskapproacheszero.

Themanagementofactuarialriskiscalledriskmanagement.

Historicalbackground

ScenarioanalysismaturedduringColdWarconfrontationsbetweenmajorpowers,notablytheU.S.andtheUSSR.Itbecamewidespreadininsurancecirclesinthe1970swhenmajoroiltankerdisastersforcedamorecomprehensiveforesight.Thescientificapproachtoriskenteredfinanceinthe1980swhenfinancialderivatives（金融衍生工具）proliferated.Itreachedgeneralprofessionsinthe1990swhenthepowerofpersonalcomputingallowedforwidespreaddatacollectionandnumberscrunching（数字运算）.

Governmentsareapparentlyonlynowlearningtousesophisticatedriskmethods,mostobviouslytosetstandardsforenvironmentalregulation,e.g."pathwayanalysis（路径分析）"aspracticedbytheUnitedStatesEnvironmentalProtectionAgency.

Riskversusuncertainty

InhisseminalworkRisk,Uncertainty,andProfit,FrankKnight（1921）establishedthedistinctionbetweenriskanduncertainty.

“

...UncertaintymustbetakeninasenseradicallydistinctfromthefamiliarnotionofRisk,fromwhichithasneverbeenproperlyseparated.Theterm"risk,"aslooselyusedineverydayspeechandineconomicdiscussion,reallycoverstwothingswhich,functionallyatleast,intheircausalrelationstothephenomenaofeconomicorganization,arecategoricallydifferent....Theessentialfactisthat"risk"meansinsomecasesaquantitysusceptibleofmeasurement,whileatothertimesitissomethingdistinctlynotofthischaracter;andtherearefar-reachingandcrucialdifferencesinthebearingsofthephenomenondependingonwhichofthetwoisreallypresentandoperating....Itwillappearthatameasurableuncertainty,or"risk"proper,asweshallusetheterm,issofardifferentfromanunmeasurableonethatitisnotineffectanuncertaintyatall.We...accordinglyrestricttheterm"uncertainty"tocasesofthenon-quantitivetype.

”

Asolutiontothisambiguityisproposedin"HowtoMeasureAnything:

FindingtheValueofIntangiblesinBusiness"byDougHubbard[2]

Uncertainty:

Thelackofcompletecertainty,thatis,theexistenceofmorethanonepossibility.The"true"outcome/state/result/valueisnotknown.

Measurementofuncertainty:

Asetofprobabilitiesassignedtoasetofpossibilities.Example:

"Thereisa60%chancethismarketwilldoubleinfiveyears"

Risk:

Astateofuncertaintywheresomeofthepossibilitiesinvolvealoss,catastrophe,orotherundesirableoutcome.

Measurementofrisk:

Asetofpossibilitieseachwithquantifiedprobabilitiesandquantifiedlosses.Example:

"Thereisa40%chancetheproposedoilwellwillbedrywithalossof$12millioninexploratorydrillingcosts".

Inthissense,Hubbardusesthetermssothatonemayhaveuncertaintywithoutriskbutnotriskwithoutuncertainty.Wecanbeuncertainaboutthewinnerofacontest,butunlesswehavesomepersonalstakeinit,wehavenorisk.Ifwebetmoneyontheoutcomeofthecontest,thenwehavearisk.Inbothcasestherearemorethanoneoutcome.Themeasureofuncertaintyrefersonlytotheprobabilitiesassignedtooutcomes,whilethemeasureofriskrequiresbothprobabilitiesforoutcomesandlossesquantifiedforoutcomes.

2.Insuranceandhealthrisk

Insuranceisarisk-reducinginvestmentinwhichthebuyerpaysasmallfixedamounttobeprotectedfromapotentiallargeloss.Gamblingisarisk-increasinginvestment,whereinmoneyonhandisriskedforapossiblelargereturn,butwiththepossibilityoflosingitall.Purchasingalotteryticketisaveryriskyinvestmentwithahighchanceofnoreturnandasmallchanceofaveryhighreturn.Incontrast,puttingmoneyinabankatadefinedrateofinterestisarisk-averseactionthatgivesaguaranteedreturnofasmallgainandprecludesotherinvestmentswithpossiblyhighergain.

Risksinpersonalhealthmaybereducedbyprimarypreventionactionsthatdecreaseearlycausesofillnessorbysecondarypreventionactionsafterapersonhasclearlymeasuredclinicalsignsorsymptomsrecognizedasriskfactors.Tertiaryprevention（medical）reducesthenegativeimpactofanalreadyestablisheddiseasebyrestoringfunctionandreducingdisease-relatedcomplications.Ethicalmedicalpracticerequirescarefuldiscussionofriskfactorswithindividualpatientstoobtaininformedconsentforsecondaryandtertiarypreventionefforts,whereaspublichealtheffortsinprimarypreventionrequireeducationoftheentirepopulationatrisk.Ineachcase,carefulcommunicationaboutriskfactors,likelyoutcomesandcertaintymustdistinguishbetweencausaleventsthatmustbedecreasedandassociatedeventsthatmaybemerelyconsequencesratherthancauses.

3.Economicrisk

Insight

Thecentralinsightinthemethodologyforincorporatingeconomicrisksarisefromtherealizationofthefactthathowevermanifoldanddiversemightbethecauses,orfactors,ofrisksaroundaspecificprojectorbusiness（forinstance,thehikeinthepriceforrawmaterials,thelapsingofdeadlinesforconstructionofanewoperatingfacility,disruptionsinaproductionprocess,emergenceofaseriouscompetitoronthemarket,thelossofkeypersonnel,thechangeofapoliticalregime,naturalcontingencies,etc.）,alloftheseareultimatelymanifestedunderonlytwoguises.AccordingtoCCFConceptiontheeconomicriskconsistsinthat:

Actualpositiveconventionalcashflows（income,inflows）turnouttobelessthanexpectedAND/ORActualnegativeconventionalcashflows（expenditures,outflows）turnouttobelargerthanexpected（inabsoluteterms）.

Suchlucidandunambiguousconceptualtreatmentofsuchacomplexandmulti-facetednotionastheeconomicriskemphasizestheverycoreofthequestion.Theeco