Chapter Two Decision Businesses Analysis.pdf

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DECISION ANALYSIS
CHAPTER TWO
02/04/2023 DECISION ANALYSIS1

INTRODUCTION
▪Decisionanalysiscanbeusedtodevelopanoptimal
strategywhenadecisionmakerisfacedwithseveral
decisionalternativesandanuncertainorrisk-filled
patternoffutureevents.
▪Decisiontheoryisananalyticandsystematic
approachtothestudyofdecision-making.
▪Agooddecisionisonethatisbasedonlogicand
considersallavailabledataandpossible
alternatives,andthequantitativeapproach
describedinthischapter.
02/04/2023 DECISION ANALYSIS2

CONT’D
Makingadecisionrequiresanenumerationof
feasibleandviablealternatives,theconsequences
associatedwithdifferentalternatives,andthe
measureofeffectivenessbywhichthemostpreferred
alternativeisidentified.
Itprovidesamethodofnaturaldecision-making
whereindataconcerningtheoccurrenceofdifferent
outcomesmaybeevaluatedtoenablethedecision-
makertoidentifysuitablealternatives.
02/04/2023 DECISION ANALYSIS3

CONT’D
Decisionmodelsusefulinhelpingdecision-makers
makethebestpossibledecisionsareclassified
accordingtothedegreeofcertainty;
•completecertainty
•completeuncertainty
•riskorprobabilisticproblems.
02/04/2023 DECISION ANALYSIS4

SOME IMPORTANT TERMINOLOGIES
Thedecisionmakeristheindividualorgroup
responsibleformakingthedecision(orsequenceof
decisions)underconsideration.
ListofAlternatives:asetofmutuallyexclusiveand
collectivelyexhaustivedecisionsthatareavailableto
thedecisionmaker.
02/04/2023 DECISION ANALYSIS5

CONT’D
StatesofNature:thesetofpossiblefutureconditions,
orevents,beyondthecontrolofthedecisionmaker.
Thisinformationmaybeintheformofjustsubjective
estimatesbasedontheexperienceorintuitionofan
individual,ortheremaybesomedegreeofhard
evidence.
Payoffs:thepayoffsmightbeprofits,revenues,costs,
orothermeasuresofvalue.Thenumberofpayoffs
dependsonthenumberofalternative/state-of-nature
combinations.
02/04/2023 DECISION ANALYSIS6

CONT’D
DegreeofCertainty:theapproachoftenusedbya
decision-makerdependsonthedegreeofcertainty
thatexists.
oneextremeiscompletecertaintyandtheotheris
completeuncertainty.Betweenthesetwoextreme,
thereisarisk.
DecisionCriteria:thedecisionmaker’sattitudetoward
thedecisionaswellasthedegreeofcertaintythat
surroundsadecision.Forexample;maximizethe
expectedpayoffs.
02/04/2023 DECISION ANALYSIS7

CONT’D
ThePayoffTable:apayofftableisadevicethata
decisionmakercanusetosummarizeinformation
relevanttoaparticulardecision.
Itincludes:
✓Listofalternative
✓Possiblefuturestateofnature
✓Thepayoffsassociatedwitheachofthe
alternative/state-of-naturecombinations.
✓Probabilities
02/04/2023 DECISION ANALYSIS8

THE PAYOFF TABLE
Where:
Ai=theithalternative
Sj=thejthstatesofnature
Pi=probabilityundereachstateofnature
Vij=thevalueorpayoffthatwillberealizedif
alternativeiischosenandeventjoccur.
02/04/2023 DECISION ANALYSIS9
State of Nature
Alternatives
S1 S2 S3
P1 P2 P3
A1 V11 V12 V13
A2 V21 V22 V23
A3 V31 V32 V33

DECISION-MAKING PROCESS
1.Identificationofthevariouspossibleoutcomes,calledthestate
ofnatureorevents,Ei’sforthedecisionproblem.Theeventsare
beyondthecontrolofthedecision-maker.
2.Identificationofallthecoursesofaction,Aj’s,orthestrategies
thatareavailabletothedecisionmaker.Thedecision-maker
hascontroloverthechoiceofthese.
3.Determinationofthepayofffunctionwhichdescribesthe
consequenceresultingfromthedifferentcombinationsofthe
actsandevents.ThepayoffmaybedesignedasVij’s.The
payoffresultingfromi
th
eventsandj
th
strategy.
4.Choosingfromamongthevariousalternativesonthebasisof
somecriterion,whichmayinvolvetheinformationgiveninstep3
onlyorwhichmayrequireandincorporatesomeadditional
information.
02/04/2023 DECISION ANALYSIS10

EXAMPLE
SupposeMr.Abemelekarealestatedevelopermustdecideonaplanfor
developingacertainpieceofproperty.Aftercarefulconsideration,Mr.
Abemelekhasleftwiththefollowinglistofacceptablealternatives.
✓Residentialproposal
✓Commercialproposal#1
✓Commercialproposal#2
Themainfactorthatwillinfluencetheprofitabilityofthedevelopmentis
whetherornotashoppingcenterbuilt,andthesizeoftheshoppingcenter,if
oneisbuilt.Supposethatdeveloperviewsthepossibilitiesas:
✓No-shoppingcenter
✓Medium–sizeshoppingcenter
✓Largeshoppingcenter
02/04/2023 DECISION ANALYSIS11

PAYOFF TABLE
02/04/2023 DECISION ANALYSIS12
State of Nature
Alternatives
No SC MS SC LS SC
Residential 400,000 1,600,0001,200,000
Commercial #1600,000 500,000 1,400,000
Commercial #2 -100,000 400,000 1,500,000

DECISION MAKING WITHOUT PROBABILITIES
Inthissectionweconsiderapproachestodecision-making
thatdonotrequireknowledgeoftheprobabilitiesofthe
statesofnature.
Theseapproachesareappropriateinsituationsinwhichthe
decisionmakerhaslittleconfidenceinhisorherabilityto
assesstheprobabilities,orinwhichasimplebest-caseand
worst-caseanalysisisdesirable.
Becausedifferentapproachessometimesleadtodifferent
decisionrecommendations,thedecisionmakermust
understandtheapproachesavailableandthenselectthe
specificapproachthat,accordingtothejudgmentofthe
decisionmaker,isthemostappropriate.
02/04/2023 DECISION ANALYSIS13

DECISION MAKING WITHOUT PROBABILITIES
There are several criteria for making decisions making
without probabilities
1.Maximax(optimistic)
2.Maximin(pessimistic)
3.Criterionofrealism(Hurwicz)
4.Equallylikely(principleofinsufficientreason/
Laplace)
5.Minimaxregret
02/04/2023 DECISION ANALYSIS14

OPTIMISTIC APPROACH
Theoptimisticapproach(MaxiMax)evaluateseach
decisionalternativeintermsofthebestpayoffthat
canoccur.
Foraprobleminwhichmaximumprofitisdesired,the
optimisticapproachwouldleadthedecisionmakerto
choosethealternativecorrespondingtothelargest
profit.
Whereas,forproblemsinvolvingminimization,this
approachleadstochoosingthealternativewiththe
smallestpayoff.
02/04/2023 DECISION ANALYSIS15

CONT’D
Themaximaxcriterionisthedecisioncriterionforthe
eternaloptimist.Hereishowthiscriterionworks:Identifythe
maximumpayofffromanystateofnatureforeachdecision
alternative.Findthemaximumofthesemaximumpayoffsand
choosethecorrespondingdecisionalternative.
02/04/2023 DECISION ANALYSIS16
State of Nature
Alternatives
No SC MS SC LS SC Max. in
Row
Residential 400,0001,600,0001,200,0001,600,000
Commercial #1600,000500,0001,400,0001,400,000
Commercial #2 -100,000400,0001,500,0001,500,000

CONSERVATIVE APPROACH
Themaximin(pessimistic)criterionchoosestheaction
withthe“best”worstoutcome.Themaximincriterion
alwayschoosesthedecisionalternativethatprovides
thebestguaranteeforitsminimumpossiblepayoff.
02/04/2023 DECISION ANALYSIS17
State of Nature
Alternatives
No SC MS SC LS SC Min. in
Row
Residential 400,0001,600,0001,200,000400,000
Commercial #1600,000500,0001,400,000500,000
Commercial #2 -100,000400,0001,500,000-100,000

MINIMAX REGRET APPROACH
Indecisionanalysis,regretisthedifferencebetweenthe
payoffassociatedwithaparticulardecisionalternativeand
thepayoffassociatedwiththedecisionthatwouldyieldthe
mostdesirablepayoffforagivenstatenature.Thisiswhy
regretisoftenreferredtoasopportunityloss.
Asitsnameimplies,undertheminimaxregretapproachto
decisionmakingonewouldchoosethedecisionalternativethat
minimizesthemaximumstateofregretthatcouldoccuroverall
possiblestatesofnature.Thisapproachisneitherpurely
optimisticnorpurelyconservative.
02/04/2023 DECISION ANALYSIS18

CONT’D
Anapproachthattakesallpayoffsintoaccount.To
usethisapproach,itisnecessarytodevelopan
opportunitylosstablethatreflectsthedifference
betweeneachpayoffandthebestpossiblepayoffin
acolumn(i.e.,givenastateofnature).
02/04/2023 DECISION ANALYSIS19

CONT’D
02/04/2023 DECISION ANALYSIS20
Opportunity Loss Table State of Nature
Alternatives
No SC MS SC LS SC
Residential 200,000 0 300,000
Commercial #1 0 1,100,000100,000
Commercial #2 700,0001,200,000 0
Original Payoff Table State of Nature
Alternatives
No SC MS SC LS SC
Residential 400,0001,600,0001,200,000
Commercial #1600,000500,0001,400,000
Commercial #2 -100,000400,0001,500,000

CONT’D
02/04/2023 DECISION ANALYSIS21
State of Nature
Alternatives
No SC MS SC LS SC Max Loss
Residential 200,000 0 300,000300,000
Commercial #1 0 1,100,000100,0001,100,000
Commercial #2 700,0001,200,000 0 1,200,000
Sincetheobjectiveistominimizemaximumlossthe
decision-makerswillchoosearesidentialalternative.

PRINCIPLE OF INSUFFICIENT REASON/
EQUAL LIKELIHOOD/ LAPLACE
Considers all the payoffs for each alternative
Find the average payoff for each alternative
Select the alternative with the highest average
02/04/2023 DECISION ANALYSIS22
State of Nature
Alternatives
No SC MS SC LS SC Raw
Average
Residential 400,0001,600,0001,200,0001066,666.67
Commercial #1600,000500,0001,400,000833,333.3
Commercial #2 -100,000400,0001,500,000600,000

THE HURWITZ CRITERION
Theapproachoffersthedecisionmakeracompromise
betweenthemaximaxandthemaximincriteria.
Requiresthedecisionmakertospecifyadegreeof
optimism,intheformofacoefficientofoptimismα,
withpossiblevaluesofαrangingfrom0to1(0<<
1).
Theclosertheselectedvalueofαisto1,themore
optimisticthedecisionmakeris,andthecloserthe
valueofαisto0,themorepessimisticthedecision
makeris.
02/04/2023 DECISION ANALYSIS23

CONT’D
If=1,thenthedecisionmakerissaidtobe
completelyoptimistic,
If=0,thenthedecisionmakeriscompletely
pessimistic.Giventhisdefinition,ifiscoefficientof
optimism,
1-iscoefficientofpessimism.
TheHurwitzcriterionrequiresthatforeach
alternative,themaximumpayoffismultipliedby
andtheminimumpayoffbemultipliedby1-.
02/04/2023 DECISION ANALYSIS24

CONT’D
If = 0.4 for the above example,
A1=(0.4x1600000)+(0.6x400000)=880,000
A2=(0.4x1400000)+(0.6x500000)=860,000
A3=(0.4x1500000)–(0.6x100000)=540,000
02/04/2023 DECISION ANALYSIS25
State of Nature
Alternatives
No SC MS SC LS SC
Residential 400,000 1,600,0001,200,000
Commercial #1600,000 500,000 1,400,000
Commercial #2 -100,000 400,000 1,500,000

DECISION MAKING WITH PROBABILITIES
•Inmanydecision-makingsituations,wecanobtain
probabilityassessmentsforthestatesofnature.
•Decisionmakingwhenthereareseveralpossible
statesofnatureandweknowtheprobabilities
associatedwitheachpossiblestate
•Mostpopularmethodistochoosethealternativewith
thehighestExpectedMonetaryValue(EMV)
02/04/2023 DECISION ANALYSIS26

EXPECTED MONETARY VALUE (EMV)
TheEMVapproachprovidesthedecisionmakerwith
avaluewhichrepresentsanaveragepayoffforeach
alternative.Thebestalternativeis,then,theonethat
hasthehighestEMV.Theaverageorexpected
payoffofeachalternativeisaweightedaverage:
EMV (alternative i)= (payoff of first state of nature)
x (probability of first state of nature)
+ (payoff of second state of nature)
x (probability of second state of nature)
+ … + (payoff of last state of nature)
x (probability of last state of nature)
02/04/2023 DECISION ANALYSIS27

CONT’D
EMV (A1) = 0.20(400000) + 0.50(1600000) + 0.30(1200000) =
1,240,000,* Max
EMV (A2) = 0.20(6) + 0.50(5) + 0.30(14) = 790,000
EMV (A3) = 0.20(-1) + 0.50(4) + 0.30(15) = 630,000
02/04/2023 DECISION ANALYSIS28
State of Nature
Alternatives
No SC MS SC LS SC
Expected
Payoff Probability
0.2 0.5 0.3
Residential 400,0001,600,0001,200,0001,240,000
Commercial #1600,000500,000 1,400,000 790,000
Commercial #2 -100,000400,000 1,500,000 630,000

EXPECTED OPPORTUNITY LOSS (EOL)
EOListhecostofnotpickingthebestsolution
•Firstconstructanopportunitylosstable
•Foreachalternative,multiplytheopportunitylossby
theprobabilityofthatlossforeachpossibleoutcome
andaddthesetogether
•MinimumEOLwillalwaysresultinthesamedecision
asMaximumEMV
•MinimumEOLwillalwaysequalEVPI
02/04/2023 DECISION ANALYSIS29

CONT’D
EOL(A1)=0.20(2)+0.50(0)+0.30(3)=130,000*Minimum
EOL(A2)=0.20(0)+0.50(11)+0.30(1)=580,000
EOL(A3)=0.20(7)+0.50(12)+0.30(0)=740,000
TheEOLapproachresultedinthesamealternativeastheEMVapproach
(Maximizingthepayoffsisequivalenttominimizingtheopportunitylosses).
02/04/2023 DECISION ANALYSIS30
State of Nature
Alternatives
No SC MS SC LS SC
Probability
0.2 0.5 0.3
Residential 200,000 0 300,000
Commercial #1 0 1,100,000 100,000
Commercial #2 700,000 1,200,000 0

EXPECTED VALUE OF PERFECT INFORMATION
(EVPI)
TheEVPIisthemeasureofthedifferencebetweenthecertainty
payoffsthatcouldberealizedunderaconditioninvolvingrisk.
IfthedecisionmakerknowsthatS1willoccur,A2wouldbe
chosenwithapayoffof$600,000.Similarly,forS2
$1600,000(forA1),andforS3,$1500,000(withA3)would
bechosen.
Hence,theexpectedpayoffundercertainty(EPC)wouldbe:
EPC=0.20(600,000)+0.50(1,600,000)+0.30(1,500,000)
=1,370,000
02/04/2023 DECISION ANALYSIS31

CONT’D
Thedifferencebetweenthisfigureandtheexpected
payoffunderrisk(i.e.,theEMV)istheexpectedvalue
ofperfectinformation.Thus:
EVPI=EPC–EMV
=1,370,000–1,240,000=130,000
TheEOLindicatestheexpectedopportunitylossdueto
imperfectinformation,whichisanotherwayofsaying
theexpectedpayoffthatcouldbeachievedbyhaving
perfectinformation.
02/04/2023 DECISION ANALYSIS32

DECISION TREES
Decisiontree,likeaprobabilitytree,iscomposedof
squares,circles,andlines:
Thesquaresindicatedecisionpointsandcircles
representchanceevents(circlesandsquaresare
callednodes)
Thelines(branches)emanatingfromsquares
representalternatives.Thelinesfromcirclesrepresent
statesofnature
Thetreeisreadfromrighttoleft.
02/04/2023 DECISION ANALYSIS33

FOLDING BACK A DECISION TREE
•Foridentifyingthebestdecisioninthetree
•Workfromrighttoleft
•Calculatetheexpectedpayoffateachoutcome
node
•Choosethebestalternativeateachdecisionnode
(basedonexpectedpayoff)
02/04/2023 DECISION ANALYSIS34

CONT’D
02/04/2023 DECISION ANALYSIS35

CONT’D
02/04/2023 DECISION ANALYSIS36

EXERCISE
WarrenBuffyisanenormouslywealthyinvestorwhohasbuilthisfortunethroughhislegendary
investingacumen.Hecurrentlyhasbeenofferedthreemajorinvestmentsandhewouldliketo
chooseone.Thefirstoneisaconservativeinvestmentthatwouldperformverywellinanimproving
economyandonlysufferasmalllossinaworseningeconomy.Thesecondisaspeculativeinvestment
thatwouldperformextremelywellinanimprovingeconomybutwoulddoverybadlyina
worseningeconomy.Thethirdisacountercyclicalinvestmentthatwouldlosesomemoneyinan
improvingeconomybutwouldperformwellinaworseningeconomy.Warrenbelievesthatthereare
threepossiblescenariosoverthelivesofthesepotentialinvestments:(1)animprovingeconomy,(2)
astableeconomy,and(3)aworseningeconomy.Heispessimisticaboutwheretheeconomyis
headed,andsohasassignedpriorprobabilitiesof0.1,0.5,and0.4,respectively,tothesethree
scenarios.Healsoestimatesthathisprofitsundertheserespectivescenariosarethosegiveninthe
followingtable.
Heestimatedapayoffvalueof30million,5million,and-10millionunderimprovingeconomy,
stableeconomy,andworseningeconomyrespectivelyinhisconservativeinvestment.Inhis
speculativeinvestmentdecision,hisestimatedpayoffvalueis40million,10million,and-30million
underanimprovingeconomy,stableeconomy,andworseningeconomyrespectively.Furthermore,he
estimatedapayoffvalueof-10million,0,and15millioninhiscountercyclicalinvestmentin
improvingeconomy,stableeconomy,andworseningeconomyrespectively.
02/04/2023 DECISION ANALYSIS37

REQUIRED
Which investment should Warren make under each of the following
criteria?
1.Maximax
2.Maximin
3. Maximum likelihood criterion
4.Hurwitz Criterionif α= .4
5.Minimaxregret
5.Construct the decision tree
02/04/2023 DECISION ANALYSIS38

PAY OFF TABLE FOR REAL ESTATE
INVESTMENT
02/04/2023 DECISION ANALYSIS39
State of Nature
Alternatives
Good Economic
Condition
Poor Economic
Condition
Probability
0.6
Appartement Building 50,000 30,000
Office Building 100,000 -40,000
Warehouse 30,000 10,000

RISK ANALYSIS AND SENSITIVITY ANALYSIS
Riskanalysishelpsthedecisionmakerrecognize
thedifferencebetweentheexpectedvalueofa
decisionalternativeandthepayoffthatmayactually
occur.Sensitivityanalysisalsohelpsthedecision
makerbydescribinghowchangesinthestate-of-
natureprobabilitiesand/orchangesinthepayoffs
affecttherecommendeddecisionalternative.
02/04/2023 DECISION ANALYSIS40

EXAMPLE
State of Nature
Strong Demand Weak Demand
Alternatives/Prob. P1= .8 P2 = .2
Small Complex (d1) 8 7
Medium Complex (d2) 14 5
Large Complex (d3) 20 -9
02/04/2023 DECISION ANALYSIS41
PAYOFFTABLEFORTHEABCCONDOMINIUMPROJECT
($MILLIONS)

RISK ANALYSIS
Adecisionalternativeandastateofnaturecombineto
generatethepayoffassociatedwithadecision.The
riskprofileforadecisionalternativeshowsthe
possiblepayoffsalongwiththeirassociated
probabilities.
02/04/2023 DECISION ANALYSIS42

CONT’D
Areviewoftheriskprofileassociatedwithanoptimal
decisionalternativemaycausethedecisionmakerto
chooseanotherdecisionalternativeeventhoughthe
expectedvalueoftheotherdecisionalternativeisnotas
good.
Forexample,theriskprofileforalternative(d2)showsa
0.8probabilityfora$14millionpayoffanda0.2
probabilityfora$5millionpayoff.Becausenoprobability
ofalossisassociatedwithdecisionalternatived2itwould
bejudgedlessriskythand3.Asaresult,adecisionmaker
mightpreferthed2eventhoughithasanexpectedvalue
of$2millionlessthanthed3.
02/04/2023 DECISION ANALYSIS43

SENSITIVITY ANALYSIS
SAcanbeusedtodeterminehowchangesinthe
probabilitiesforthestatesofnatureorchangesinthe
payoffsaffecttherecommendeddecisionalternative.
Inmanycases,theprobabilitiesforthestatesof
natureandthepayoffsarebasedonsubjective
assessments.
Sensitivityanalysishelpsthedecisionmaker
understandwhichoftheseinputsarecriticaltothe
choiceofthebestdecisionalternative.
02/04/2023 DECISION ANALYSIS44

CONT’D
Oneapproachtosensitivityanalysisistoselect
differentvaluesfortheprobabilitiesofthestatesof
natureandthepayoffsandthenresolvethedecision
analysisproblem.Iftherecommendeddecision
alternativechanges,weknowthatthesolutionis
sensitivetothechangesmade.
02/04/2023 DECISION ANALYSIS45

CONT’D
ThebestalternativeforABC,therealstatedeveloper
willselectbasedonEMVisthelargecomplex.
EMV A1: = 0.8(8) + 0.2(7) = 7.8
A2: = 0.8(14) + 0.2(5) = 12.2
A3: = 0.8(20) + 0.2(-9) = 14.2* maximum
Oneapproachtosensitivityanalysisistoselect
differentvaluesfortheprobabilitiesofthestatesof
natureandthepayoffsandthenresolvethedecision
analysisproblem.
02/04/2023 DECISION ANALYSIS46

CONT’D
Forthespecialcaseoftwostatesofnature,a
graphicalprocedurecanbeusedtodeterminehow
changesfortheprobabilitiesofthestatesofnature
affecttherecommendeddecisionalternative.
Todemonstratethisprocedure,weletPdenotethe
probabilityofstateofnatureS1;thatis,P(S1)=P.
Withonlytwostatesofnature,theprobabilityofstate
ofnatureS2isP(S2)=1-P(S1)=1-P.
02/04/2023 DECISION ANALYSIS47

EXPECTEDVALUEFORTHEABCDECISION
ALTERNATIVESASAFUNCTIONOFP
02/04/2023 DECISION ANALYSIS48

CONT’D
Conclusion:decisionalternatived1providesthe
largestexpectedvalueforP≤0.25,decision
alternatived2providesthelargestexpectedvalue
for0.25≤P≤0.70,anddecisionalternatived3
providesthelargestexpectedvalueforP≥0.70.
02/04/2023 DECISION ANALYSIS49

COMPUTING BRANCH PROBABILITIES
WITH BAYS' THEOREM
•Allowsprobabilityvaluestoberevisedbasedon
newinformation(fromasurveyortestmarket)
•Priorprobabilitiesaretheprobabilityvaluesbefore
newinformation
•Revisedprobabilitiesareobtainedbycombiningthe
priorprobabilitieswiththenewinformation
02/04/2023 DECISION ANALYSIS50

CONT’D
Thestepsusedtodevelopthistableareasfollows:
Step1.Incolumn1enterthestatesofnature.Incolumn2enterthe
priorprobabilitiesforthestatesofnature.Incolumn3enterthe
conditionalprobabilitiesofafavourablemarketresearchreport(F)
giveneachstateofnature.
Step2.Incolumn4computethejointprobabilitiesbymultiplyingthe
priorprobabilityvaluesincolumn2bythecorrespondingconditional
probabilityvaluesincolumn3.
Step3.Sumthejointprobabilitiesincolumn4toobtainthe
probabilityofafavourablemarketresearchreport,P(F).
Step4.Divideeachjointprobabilityincolumn4byP(F)=0.77to
obtaintherevisedorposteriorprobabilities,P(S1/F)andP(S1/F).
02/04/2023 DECISION ANALYSIS51

CONT’D
02/04/2023 DECISION ANALYSIS52
IntheABCproblemweassumethatthefollowing
assessmentsareavailablefortheseconditional
probabilities:
Market Research
State of Nature Favourable, FUnfavourable, U
Strong demand, S1P(F/S1)= 0.90P(U/S1)= 0.10
Weak demand, S2P(F/S2)= 0.25P(U/S2)= 0.75

CONT’D
BranchProbabilitiesforTheABCCondominiumProjectBased
OnAFavourableMarketResearchReport
02/04/2023 DECISION ANALYSIS53
State of
Nature
Prior
Probabilities
Conditional
Probabilities
Joint
Probabilities
Posterior
Probabilities
Sj P(Sj) P(F/Sj) P(F ∏Sj) P(Sj/F)
S1 0.8 0.90 0.72 0.94
S2 0.2 0.25 0.05 0.06
1 P(F) = 0.77 1
Notethattheprobabilityofobtaininganfavourablemarketresearch
reportisP(F)=0.77.Ifanfavourablereportisobtained,theposterior
probabilityofastrongmarketdemand,S1is0.94andofaweak
marketdemand,S2,is0.06.

CONT’D
BranchprobabilitiesfortheABCcondominiumprojectbased
onanunfavourablemarketresearchreport
02/04/2023 DECISION ANALYSIS54
State of
Nature
Prior
Probabilities
Conditional
Probabilities
Joint
Probabilities
Posterior
Probabilities
Sj P(Sj) P(U/Sj) P(U ∏Sj) P(Sj/U)
S1 0.8 0.10 0.08 0.35
S2 0.2 0.75 0.15 0.65
1 P(U) = 0.23 1
Notethattheprobabilityofobtaininganunfavourablemarketresearch
reportisP(U)=0.23.Ifanunfavourablereportisobtained,the
posteriorprobabilityofastrongmarketdemand,S1is0.35andofa
weakmarketdemand,S2,is0.65.

DECISION-MAKING WITH UTILITIES
Thusfar,whenapplyingBayes’decisionrule,wehaveassumed
thattheexpectedpayoffinmonetarytermsistheappropriate
measureoftheconsequencesoftakinganaction.However,in
manysituationsthisassumptionisinappropriate.
Thetermutilityisthemeasureofpreferenceforvarious
alternativesintermsofrelativevalueformoney.Theutilityofa
givenalternativeisuniquetotheindividualdecision-makersand
unlikeasimplemonetaryamount,canincorporateintangible
factorsorsubjectivestandardsfromtheirownvaluesystems.
02/04/2023 DECISION ANALYSIS55

CONT’D
Theutilityprovidesawayofincorporatingthe
decisionmaker’sattitudetowardriskinarrivingata
decisionandhencemeasuresthetruevalueofan
outcome.
•AnalternativetoEMV
•Peopleviewriskandmoneydifferently,soEMVis
notalwaysthebestcriterion
•Utilitytheoryincorporatesaperson’sattitudetoward
risk
•Autilityfunctionconvertsaperson’sattitudetoward
moneyandrisksintoanumberbetween0and1
02/04/2023 DECISION ANALYSIS56

CONT’D
Monetaryvalueisnotalwaysatrueindicatorofthe
overallvalueoftheresultofadecision
TheoverallvalueofadecisioniscalledUTILITY
Rationalpeoplemakedecisionstomaximizetheir
utility
02/04/2023 DECISION ANALYSIS57

CONT’D
Utilityassessmentassignstheworstoutcomeautility
of0,andthebestoutcome,autilityof1
Astandardgambleisusedtodetermineutilityvalues
Whenyouareindifferent,theutilityvaluesareequal
02/04/2023 DECISION ANALYSIS58

GENERAL PROCEDURES
Step1.Developapayofftableusingmonetaryvalues
Step2.Identifythebestandworstpayoffvaluesinthe
tableandassigneachautility,withU(bestpayoff)>
U(worstpayoff)
Step3.ForeveryothermonetaryvalueMintheoriginal
payofftable,dothefollowingtodetermineitsutility:
a.Definethelotterysuchthatthereisaprobabilitypof
thebestpayoffandaprobability(1-p)oftheworst
payoff
02/04/2023 DECISION ANALYSIS59

CONT’D
b.Determinethevalueofpsuchthatthedecisionmakeris
indifferentbetweenaguaranteedpayoffofMandthelottery
definedinstep3(a)
c.CalculatetheutilityofMasfollows:
U(M)=pU(bestpayoff)+(1-p)U(worstpayoff)
Step4.Converteachmonetaryvalueinthepayofftabletoa
utility
Step5.Applytheexpectedutilityapproachtotheutility
tabledevelopedinstep4andselectthedecisionalternative
withthehighestexpectedutility
02/04/2023 DECISION ANALYSIS60

EXAMPLE CONT’D
PAYOFF TABLE FOR SWOFFORD, INC.
02/04/2023 DECISION ANALYSIS61
Decision
Alternative
State of Nature
Prices Go Ups S1
P = .3
Prices Stable S2
P = .5
Prices go Down S3
P = .2
Investment A, d1 30000 20000 -50000
Investment B, d2 50000 -20000 -30000
Investment C, d3 0 0 0
EMV A1: = 0.3(30000) + 0.5(20000) + .2(-50,000)= 9000
A2: = 0.3(50000) + 0.5(-20000) + .2(-30,000)= 2000
A3: = 0.3(0) + 0.5(0) + .2(0) = 0

CONT’D
Best Payoff = 50, 000 10
Worst Payoff = -50, 000 0
02/04/2023 DECISION ANALYSIS62
Monetary Value Indifference
Value of P
Utility
50,000 Doesn’t apply 10
30,000 .95 9.5
20,000 .90 9
0 .75 7.5
-20,000 .55 5.5
-30,000 .40 4.0
-50,000 Doesn’t apply 0

CONT’D
UTILITY TABLE FOR SWOFFORD, INC.
02/04/2023 DECISION ANALYSIS63
Decision
Alternative
State of Nature
Prices Go Ups S1
P = .3
Prices Stable S2
P = .5
Prices go Down S3
P = .2
Investment A, d1 9.5 9.0 0
Investment B, d2 10 5.5 4
Investment C, d3 7.5 7.5 7.5
EU A1: = 0.3(9.5) + 0.5(9) + .2(0)= 7.35
A2: = 0.3(10) + 0.5(5.5) + .2(4)= 6.55
A3: = 0.3(7.5) + 0.5(7.5) + .2(7.5) = 7.5

LINKS
https://www.solver.com/
https://treeplan.com/
02/04/2023 DECISION ANALYSIS64

END
02/04/2023 DECISION ANALYSIS65