UNIVERSITYOFECONOMICS INSTITUTE VIETNAM THENETHERLANDS VIETNAM-NETHERLANDS PROGRAMMEFOR M.A.INDEVELOPMENTECONOMICS... DECLARATION...i ACKNOWLEDGEMENTS...ii ABSTRACT...iii TABLE OFCONTENT
Trang 2UNIVERSITYOFECONOMICS INSTITUTE
VIETNAM THENETHERLANDS
VIETNAM-NETHERLANDS PROGRAMMEFOR M.A.INDEVELOPMENTECONOMICS
Trang 4ACKNOWLEDGEMENTS
FirstandforemostIwouldliketooffermygratitudetomysupervisor,Dr.LeCongTru,forinvaluablecomments,remarksandengagementthrought h e l e a r n i n g processo f t h e t h e s i s ThenIhaveMr.LeDucAnhtothankforintroducingmetothetopic.Iamalsomuchobligedt o AssociateProf.Dr.NguyenTrongHoai,Dr.PhamKhanhNamandDr.LucaTasciottiforhelpfulremarksonmyTRDaswellaskeepingmeontherighttrack.Fortheavailabilityoft h e dataset,IamthankfultoMDE.TranThuTrangfromtheHeadOfficeofBIDV.Lastbutn o t least,Iamdeeplyindebtedtomyparents,mydearlybelovedwife,mybrothersandsistersf o r alltheunderstandingandspiritualassistance.Iwillwholeheartedlybegratefulforeverforyourlove
Trang 5ABSTRACT
Duetointensecompetition,over-lendingandeconomicturmoil,bankingsysteminVietnami s performingloans.Giventheconsiderablegrowthofretailbankingmarket,anexplorationofriskpredictorsbecomescrucialmorethanever.Thispaperinvestigateskeyfactorst h a t influencel o a n repaymentperformanceamongi n d i v i d u a l customers.T h e s u r v e y coversa representativesampleo f personall o a n s fromo n e oft h e largestVietnamesecommercialbanks.A logistic regressiontechniquei s employedto evaluatetherelationshipbetweendelinquencyandborrowercharacteristicsandloanfeatures.Theregressionr e s u l t s revealthatborrowercharacteristics,e.g.b o r r o
sufferingahugeamountofnon-w i n g
history,bank-accountholdingandeducationlevel,ratherthanloanfactors,suchaspurposes,durationandcreditl i m i t , haves t r o n g e r effectso n t h e defaultoutcome.T h i s s u g g e s t s t h a t b a n k e r s a p p l y appropriateadjustmentstoborrowercharacteristicstominimize defaultrisk
Keywords:retailbanking,creditscoring,default,risk,logisticregression,probability.
Trang 6DECLARATION i
ACKNOWLEDGEMENTS ii
ABSTRACT iii
TABLE OFCONTENTS iv
LISTOFTABLES vii
LISTOFFIGURES vii
LISTOFABBREVIATIONS viii
Chapter1 INTRODUCTION 1
1.1 Background 1
1.2 Problemstatement 2
1.3 Researchobjectives 3
1.4 Researchquestions 4
1.5 Justificationofthe study 4
1.6 Scopeof thestudy 4
1.7 Organizationofthe study 5
Chapter2LITERATUREREVIEW 6
2.1 Historyofcreditscoring 6
2.2 Conceptsofcreditscoring 7
2.3 Reviewsofeconomictheories 10
2.4 Reviewsofempiricalstudies 12
2.4.1 Defaultpredictorsinmarketsforcreditcards andinstantloans 12
2.4.2 Defaultpredictorsinmarketsforautomobiles,mortgagesandrealpropertyconstructio n 14
2.4.3 Defaultpredictorsinmarketsforindividualloans 16
2.5 Chaptersummary 17
2.5.1 Empiricalliteraturesummary 17
2.5.2 Problems andlimitationsofpreviousstudies 20
2.5.3 Conceptualframework 21
Chapter3DATAANDRESEARCHMETHODOLOGY 22
Trang 73.1 Datacollection 22
3.2 Variablesmeasurements 23
3.2.1 Responsevariable 23
3.2.2 Explanatoryvariables 24
3.2.2.1 Borrowercharacteristics 24
3.2.2.2 Loancharacteristics 27
3.3 Researchmethodology 28
3.3.1 Descriptive analysis 28
3.3.2 Econometricmodel 29
3.3.2.1 Methodologiesfor CSM 29
3.3.2.2 Logisticregression 30
3.4 Validation 32
3.4.1 Overallevaluations 33
3.4.2 Statisticaltestsofindividualpredictors 34
3.4.3 Goodness-of-fitstatistics 34
3.4.3.1 PseudoR-squaredstatistics 34
3.4.3.1.1 CoxandSnell'sR2 34
3.4.3.1.2 Nagelkerke'sR2 35
3.4.3.2 HosmerandLemeshowtest 35
3.4.4 Validationsofpredictedprobabilities 36
3.4.4.1 Classificationtable 36
3.4.4.2 Areaunder theROC curve 37
3.5 Analyticalframework 38
3.6 Chaptersummary 38
Chapter4DATAANALYSISANDRESULTS 39
4.1 Descriptive statistics 39
4.1.1 Personaltastesforloansbyages 41
4.1.2 Discretionaryincomes anddefault 42
4.1.3 Nexusbetweenloan amount andloanoutcomes 43
4.1.4 Loandurationandloan outcomes 43
4.1.5 Collateralvalueandloanoutcome 44
4.1.6 Differencesinvariablesbetweendefaultedandnon-defaultedloans 45
4.1.7 Correlationmatrixamongindependentvariables 45
4.2 Informationvalue 46
Trang 84.3 Empiricalresults 48
4.3.1 Modelestimation 48
4.3.2 Assumptionverification 50
4.3.3 Modelvalidation 51
4.3.3.1 Overallevaluationsandstatisticaltestsofindividualpredictors 51
4.3.3.2 Goodness-of-fitstatistics 52
4.3.3.3 Validationsofpredictedprobabilities 52
4.3.3.3.1 Classificationtable 52
4.3.3.3.2 Receiveroperatingcharacteristicandareaunder the ROCcurve 53
4.3.4 Resultinterpretation 53
4.3.4.1 Borrowercharacteristics 54
4.3.4.2 Loancharacteristics 56
4.4 Chaptersummary 57
Chapter5CONCLUSIONANDPOLICY IMPLICATIONS 58
5.1 Conclusion 58
5.2 Policyimplications 59
5.3 Limitationsandfurtherstudies 62
REFERENCES 63
APPENDIX 67
Trang 9LISTOFTABLES
Table2.1.Creditscoringvs.Creditrating 9
Table2.2 Summaryofvariables 18
Table3.1.Overviewofvariables 31
Table3.2.Predictiveaccuracyof CSMs 36
Table4.1.Variablesinitiallyconsideredfor theCSM 40
Table4.2.Loantypestatistics 41
Table4.3.Loanduration 43
Table4.4.Differencesinvariablesbetweenthe loanoutcomes 45
Table4.5.Correlationcoefficientsamongcontinuousindependentvariables 46
Table4.6.Informationvaluesforexplanatoryvariables 47
Table4.7.Regressionresults 49
Table4.8.Classificationtable 52
Table4.9.Performanceofthemodels 53
LISTOFFIGURES Figure2.1.Processof creditscoring 8
Figure2.2 Conceptualframework 21
Figure3.1 ROCCurveandAUC 37
Figure3.2 Steps in binarylogisticregression 38
Figure4.1.Genderandloan sample 39
Figure4.2 Averageloansizevs.ageandpurposes 42
Figure4.3.Defaultfrequenciesamongdifferent groups ofdiscretionaryincomes 42
Figure4.4.Defaultfrequenciesamongdifferent groups ofloanamounts 43
Figure4.5.Defaultfrequenciesamongdifferent groups ofloanduration 44
Figure4.6.Defaultfrequenciesamongdifferent ratios ofcollateral-to-loan 44
Figure4.7 ROCcurvesandAUC 53
Trang 11Chapter1 INTRODUCTION
Thischapterintroduces t h e thesis topic andidentifi esthe main issueswh ic h will
be coveredi n t h e f o l l o w i n g s e c t i o n s Theb a c k g r o u n d andm o t i v a t i o n t o t h e s t u d
y w i l l comefirst.Thentheresearchobjectives,researchquestionsandscopewillbeintroduced.Thenextw i l l bethemaincontributionofthestudyandthethesisstructureistobebrieflydisplayeda
tt h e endofthechapter
1.1 Background
Ins p i t e o f t h e w i d e v a r i e t y o f b a n k i n g b u s i n e s s e s , providingl o a n s
f o r corporatecustomersandindividualsconstitutesthemajorityofproceedsforcommercialbanksaswellasothercreditinstitutions.Asinformationasymmetriesprevail,lendersaretradingwitharisk
o f borrowersfallingindefault(Stiglitz&Weiss,1981).However,asymmetricinformationisn o
t theonlythreatsincesocialfactorsalongwitheffectsofbusinesscyclesmayalsoimpactu p o n t
h e d e l i n q u e n c y ( Allen,DeLong,& S a u n d e r s , 2 0 0 4 ).T o advocatel e n d i n g activities,measurementofcreditriskhasbeentakenseriouslyandthereforehasmadedramaticprogressovert w o pastdecades( Altman& Saunders,1 9 9 7 ).Theset w o scholarsp o i n t o u t severalforcesthatgiveimpulsetocredit-riskmeasurement Theyinvolve:
(1)aworldwideincreasei n caseso f b a n k r u p t c i e s ,
( 2 ) disintermediationtrendbyt h e largestborrowersandhighestquality,
(3)marginalcompetitivenessonloans,
(4)adecreasingvalueofproperty( a n d collateralasa result),a n d ( 5 ) a sharpr i s e i n
off-balancesheeti n s t r u m e n t s AfterBankf o r InternationalSettlements(BIS)haslaunchedtherevisedframeworkBaselII,banksareencouragedtopromotetheirapproachesoncredit-
riskmeasurement(Claessens,Krahnen,&Lang,2005)andvendorsstarttoofferimprovedmodelstobanksforcalculatingther e g u l a t o r y capitalrequirements
Togetherwiththerapidincreaseinbankloansforcorporatesandinstitutions,theneedo f i n d
i v i d u a l creditt o d a y i s ati t s highest( Brown,Taylor,& W h e a t l e y P r i c e , 2005)and" l e n
d i n g boomappearstob e pa rt ic ul a rl y strongi n t h e segmento f l oa ns t o h o u s e h o l d s , " asarguedbyBackéandWójcik(2008).Unlike thewholesalebankingwhich tradeswithlargeandt
y p i c a l l y r a t e d borrowers,t h e retailbankingd e a l s w i t h s m a l l l o a n s i z e s anda hug
en u m b e r ofpersonalclientswho,inmostcases,havenocreditratingsatall.Sinceeachloanisr e l a
t i v e l y notlargei n a m o u n t , i t i s impliedt h a t t h e r i s k o f defaulto n anypersonall o a n i s q u i t
e minimal.Traditionally,a l o a n approvali s basedo n t h e creditofficer'sjudgmento r
Trang 12experiencefrompreviousdecisions.However,itiscostlyandtime-consumingforeachloanprofiletobeexaminedseparately.Infact,nolossonanyseparateretailloancanputabankcloset o insolvency.Hence,u n i t costf o r appraisingthe defaultr i s k o f a retaill o
a n m a y belargerthantherewardintermsoflosspreventionanditmightnotbeworthwhiledeterminingt h e riskonthebasisofanindividualloan.Asaresult,tomeasurethelevelofcreditriskasaw h
o l e f o r s u c h i n d i v i d u a l l o a n segmentation,b a n k s u s e l o a n defaultp r e d i c t i n g m o d
e l s orcredits c o r i n g m o d e l s ( C S M s ) w h o s e goali s t o forecastbadoutcomesandm a k e s u r
e t h a t goodloansarenot falselyrejectedandbadloansarenot wronglyacceptedeither
Accordingt o Yang,N i e , andZ h a n g ( 2 0 0 9 ) ,t h e creditr a t i n g ofb a n k s hast h
(2)Creditscoring,and(3)Probabilityofdefaultmodel.Sofartherehavebeenmanygoodremarksassociatedwiththoseapproachesasfollows.Brill(1998)arguesthatbuildingandrefiningaCSMcanhavecertainbenefitss u c h ascostsavingi n creditassessment,fastercreditanalysisandimprovementi n cashf l o w andcollections.ChenandH u a n g ( 2003)accountt h a t w i t h considerablel o a n portfolios,just
aslightenhancementincreditscoringauthenticitycanlowerthelenders'riskandtranslates i g n i f i c
a n t l y in to
latersavings.Fishelson-Holstine(2004)provest h a t C S Ms aredevisedtoaccommodatetheneedofincreasingloanvolume,mitigatingcreditrisksandtreatingcustomerimpartially.Thati s t h e reasonw h y s u c h t o o l sarebeneficialt o b o t h institutionalcreditorsandborrowers.Inthesameway,Allenetal
(2004)reckonthatbanksapplyingCSMstendtobemoreefficientatlowercosts.DinhandKleimeier(2007)insistt h a t ifagoodmodelisemployedwiththeavailabilityofreliabledata,scorin
th e risk.Noticeably,theBoardofGovernorsoftheFederalReserveSystem(2007)reportstothe Congressthat "creditscoringreducesthecostoflending orfacilitatesmoreeffectiverisk-
basedpricingofloans,increaseduseofcreditscoringmayexpandtherangeo f applicantstowhom lendersare ableto makeloansprofitably"(pp.42-43)
1.2 Problemstatement
BankingsectorinVietnamhasbeengrowingsignificantlyinthelastdecade.AreportbyMcKinseyGlobalInstitute(2012)revealsthattotalbankcredittoGDPi n nominallocalc u r r e n c yhasincreasedsharply fromapproximately 22%asof2000tomorethan120%tenyearslater,equivalentto33%annualgrowthwhichisthehighestamongneighboringcountries:India,C h i n a, Indonesia,Malaysia,Thailandandt h e Philippines.T h e statisticalfigurerevealsthatVietnamese
Trang 13economytotallydependsonthebanks'sourcesnowjustafteronedecade.Therapidexpansioninbanks'lendingwillalsobringnon-performingloans(NPLs).
Trang 14Whilethereportedlevelofbadloansappearstobeundercontrol,thetruevolumeislikelytob e muchhigherthanwhatispublicized.Inreality,NPLsclimbupto10%inMay2012,4%higherthanthatin2011andequalto10%oftheyear'sGDP.1Therefore,thesituationisanurgefor
astricterstandardofbaddebtrecognitioninordertomanagecreditrisk,especiallyint h e contextofglobalfinancialcrisis,Vietnameseeconomicdownturnandintensecompetitionoverthepastfewyears
AsVietnam'sb a n k i n g marketi s maturing,b a n k s havet o dealw i t h competitionn o t o n
l y
fromotherdomesticcreditinstitutionsbutfromwell-performingforeignbanksaswell.Despitethefactthatretailbankinghasbeengrowingrapidlyoverrecentyears,BIDVhasnottakenthistrendseriously
Anewchapteropensafteritsinitialpublicoffering(IPO),2t h ebankhappenst o perceivet h a t t h e wholesaleb a n k i n g a c t i v i t i e s cannotb e enoughf o r growtha n d prosperity,andthusnotguaranteeitsleadingroleinVietnam'sbankingsector.Consequently,recentchangesandd e v e l o p m e n t s i n t h
e fieldofb a n k i n g h a v e l e d t h e bankt o a renewed
interestinretailsegment.Sinceitisnoteconomicaltodevoteextensiveresourcestoanalyzepersonalcreditr i s k o f defaulto n a case-by-
casebasis,a CSMiso f importanceinstead.A s BIDVisoneofthelargestbanksinVietnamwithanationwidenetworkontheonehandandt h e standardo f baddebtclassificationhast o c o m p l y witht h
e s t a t e regulationo n t h e o t h e r hand,t h e implicationsint h e empiricalstudyatt h i s bankcanbegeneralizedf o r th e w h o l e Vietnamesebankingsystem
1.3 Researchobjectives
Thiss t u d y aimsatdistinguishinga goodr i s k f r o m a badr i s k , therefore,t h e keypurposei s t o e x a m i n e factorst h a t causedefaulti n personall o a n s andh o w t h e proposedmodelscanhelptomanagecreditrisk.Inpursuitofthis,theresearchattemptstofocusontherelationshipbetweentheloanoutcomesandborrowercharacteristics(e.g.housing,employmentstatusandincomelevel)andloancharacteristics(e.g.interestrate,collateraltypeandvalue).3M o r especifically,t h i s papermeasurest h e i m p a c t o f l o a n s i z e , durationandpurposeson
Trang 15uponpersonaldefaultswoulddependonthewholeeconomiccycle.However,therearesomevariablesthatcanb e subje ctedtochangesinthemacroeconomy.Suchvariablesareincome,interestrateandloanduration.
Trang 161.4 Researchquestions
Toanswertheoverallaim,theresearchquestionsareasfollows
Mainquestion:Whatarethedeterminingfactorsthatimpactthedebtors'performancei n personalloans?
economicchangesafterthe2007USmortgagecrisis,whichsparkedaworldwidetougheconomicti
me.Third,am o d e l w i t h o u t t h e typicallysignificantl o a n characteristic,d i s c r e t i o n a r
y incomes,i s constructedtoprovidethebankwithpossiblecheckingformisinformationorpotenti
alfraud.Especially,theresearchtakesintoaccountthecreditprofileofclientstostudyhowthosewithdifferentb o r r o w i n g h i s t o r i e s i n c l i n e t o b e h a v e w i t h t h e i r currentl o a n s Finally,t
h e constructedmodelsaresubjecttoawiderangeofvalidationtestingtoinsuretheirreliabilityandgeneralization
1.6 Scopeofthestudy
Lendingprocessi s a r e l a t i v e l y straightforwardserieso f a c t i o n s i n v o l v i n g t w o principleparties.Theseactionsgofromthei n i t i a l l o a n applicationt o t h e successfulrepaymentoftheloanoritsdefault.Inlendingactivities,SummersandWilson(2000,p
38)summarizes i x functionalresponsibilitiesb a s i c a l l y connectedwithgrantingcredittoclients.Theyinvolve:(1)assessmentofclients'creditrisk,
(2)makingcreditgrantingdecisionw i t h regardt o termsandl i m i t s ,
( 3 ) collectingd u e receivables(debts)anda c t i n g againstdefaulters,
( 4 ) mo ni to ri ng clients'behavior andcompilingmanagementi n f o r m a t i o n ,
(5)bearingrisk ofdefault,and(6)financingtheinvestmentinreceivables
Trang 17Thisresearchinvestigatest h e f o u r t h o f t h e s i x l e n d i n g responsibilities.Hence,t h ewritingconcentratesonstatisticaldatacollectionofcustomerbehaviorsandtriestodiscovermanagerialoutcomefromanalyzingthedatawhichiscollectedinthe2008-
2011period.Thescopeofthestudyisdefinedtoincludeconsumercredit(coveringautomobiles,recreationalvehicles,education,creditcards,etc.),homeimprovementloansormortgagesforpurchasinga house.Individualloanswith businesspurposesarealsoincludedin the research.4
1.7 Organizationofthestudy
Ther e m a i n i n g o f t h e e s s a y i s organizedi n t h e f o l l o w i n g way.T h e s e c o n d chapterbeginsbyl a y i n g o u t t h e h i s t o r y ofdefaultpredictingandt h e n l o o k s att h e theoreticalandempiricaldimensionsoftheresearch.Chapter3describesthedata,researchmethodologyandcriteriaf
o r a s s e s s i n g t h e q u a l i t y o f t h e econometricm o d e l s C h a p t e r 4 analysest h e data,reportsthefindingsandevaluatestheresults.Thelastchapterconcludesthepaperwithpolicyimplicationsanddiscussesthe limitationsanddirectionsforfurtherstudies
Trang 184 CSM's
roleisimportantinthe
BaselIIimplementationforretailportfolio.Smallloansforbusinesspurposeswithamountslessthan$1,000,000intheU.S.and managedonapooledbasisarecategorizedasretailcredits.
Trang 19Chapter2 LITERATUREREVIEW
Thepurposeofthischapteristoreviewtheoreticalandempiricalliteratureondefaultpredictorsinretailbanking.Thechapterisdividedintosixsub-
sections Thefirsttwopartsd i s c u s s
t h e h i s t o r y aswellasconceptsofcreditscoring.The nexttwopartscovert h e economictheoriesandempiricalstudiesonthesubject.Thenextonesummarizesempiricalliterature;especiallyitrecallsthesignificanceofthemanyvariablesthatareusedtopredictcreditperformance.Thefinalpartprovidessummaryofdeterminantsofcreditdefaultintheempiricalliterature
2.1 Historyofcreditscoring
Mostacademicwriterscitea reportbyDurand(1941)releasedthroughtheNationalBureauofEconomic Research(NBER)astheearlieststatisticalapproachtothe issueofcreditapplicationselection.Inthe1940stheso-
calledcreditscorecardsystemswereimplementedf o r somemailorderfirmsandfinancialcreditsuppliers(Lawrence&Solomon,2002).However,itwasnotuntil1958thattheinitialcommercialratingsystemswerecreatedbyBillFairandE a r l Isaacf o r AmericanInvestment,a financecorporationl
o c a t e d i n S t Louis,M i s s o u r i
(Fishelson-Holstine,2004).Theirfirstprojectswereprovedtobesuccessfulasthosescoringsystemshelpedtoreducedefaultcasesupto20-30percentwhile sustainingsimilarvolumes;theycouldalsobeusedtomaximizelendingamountby20-30 percent with thesamedelinquentlevel
TheexerciseofCSMbecamemorewidespreadintheearly1960swhenthebusinesso f creditcardmaturedandtheneedfordecision-
makingspeedbecamenecessary(Anderson,2007).Aftert h a t , credits c o r i n g p r o c e s s i n g wasappliedt o o t h e r c u s t o m e r c l a s s e s Att h i s p o i n t , MyersandForgy(1963)madeacomparisonbetweendiscriminantanalysisandregressioni n r a t i n g applications.Later,a b a n k
r u p t c y p r e d i c t i o n m o d e l wasdescribedbyBeaver(1966).T h e s e w o r k s focusedo n t
w o a s p e c t s : failurep r e d i c t i o n andcreditq u a l i t y classification.AccordingtoAllenetal.(2004),themostusedtraditionalCSMwasthe1968m u l t i p l e discriminantanalysisforcorporationsbyAltman.Morethanonedecadelater(1980),t h e sameauthorintroducedth e basislendingprocessforbanksasanintegratedsystemandm a d e ananalysison howto setthecriteriaforcommercialloanassessment
Trang 20The1960s,accordingtoRitter(2012),alsowitnessedadramaticallyincreasingattentiont o
a m a t t e r o f equality,s p e c i f i c a l l y i n t h e c o n t e x t o f t h e AmericanC i v i l RightsMovement.Inthosedays,singlewomen,divorcees,orwidowscouldnotgetamortgageloanw i t h o u t providingamalerelativeasaco-signer.Inaddition,minorityapplicants,particularlyAfrican-Americanb o r r o w e r s , ande l d e r l y customersexperiencedl i m i t e d o p t i o n s i n gainingcredit.Underthecircumstances,theEqualCreditOpportunityAct(ECOA)wasimplemented.T h e 1 9 7
4 E C O A makesi t illegali f creditorsdiscriminateagainstt h e i r applicantso n t h e groundso f "race,color,religion,nationalo r i g i n , s e x , maritals t a t u s , o r age(providedt h e applicanthast h e
c a p a c i t y t o c o n t r a c t ) " (ECOA,1 5 U S C 1 6 9 1 ets e q , Part2 0 2 , Section202.1).Sincethen,consumercreditdecisionshaveconsiderablyreliedmoreoncredithistoryprovidedbycreditreportingagenciesthathaveusedverifiabledatatobuilduptheircomputerizedfiles
Thankstothesurgeofautomatedstatisticalcreditratingandmortgagescoringasanapproachtoapprovingandunderwritingloans,housingfinanceevolvedinthe1990s.Automated
u n d e r w r i t i n g , whichwaspreviouslyemployedi n creditcardbusinessandautomobileloans,hasturnedintothemostimportantmortgageunderwritingapproache s p e c i a l l y s i n c e 1 9 9 5 (Straka,2 0 0 0 ).Besidest h e CSM'swiderandwideru s e i n m o r t g a g e origination,Mester(1997)demonstratedthatasmanyas97%ofbankshaveemployedCSMst o evaluatecreditc a r d applicationsw h i l e 7 0 % o f themhavet a k e n o n s u c h t o o l s f o r t h e i r s m a l l businessfinancing.SinceAltman'straditionalCSM,therehavebeenothermethodologiesformeasurementofcreditrisk.Inaccordancewith Al le n etal
(2004),therearef o u r approachesi n dealingw i t h multivariateC S M s :
( 1 ) l i n e a r p r o b a b i l i t y m o d e l , ( 2 ) logisticmodel,
(3)probitmodel,and(4)multiplediscriminantanalysismodel.Allofthefourm o d e l s canbesuccessfulinpickingoutvariablesthathavepredictivepowertodifferentiatedefaultersfromnon-defaulters
Trang 21ng predicting
Scoring model
X 11 , X 12 , X 13 , Y 1 = ?
X 21 , X 22 , X 23 , Y 2 = ?
X n1 , X n2 , X n3 , Y n = ?
Source: Liu Yang ()
mount).Theseassessmentslaythefoundationonthecreditor'sownexperiencewithhistoricalinformationa n d a vi ew o f t h e a p p l i c a n t s ' prospectst a k e n i n t o account.Andersone x p l a i n s thatthisapproachissuitableforcommunitieswherethelendersandborrowershavep e r s o n a l l y knowneachother.However,itisnotefficientinmoderntimeofextendedbranchnetworksandcustomermobility.Regardingcreditdecisionbasedonsuchjudgmentalsystem,evenatitsbest,isstillinaccurate.Fishelson-Holstine(2004)reckonsthecreditor'srule-
basedsystemsasa serieso f h u r d l e s Eachapplicanth a s t o fulfillallt h e c r i t e r i a i n o r d e r t
o b e approvedwhereaseachfactorisregardedinisolation.Therefore,itisunlikelyforstrengthstooffs etweaknesses.
Onthecontrary,aCSMperformsarigorousanalysisofavailabledataandisbasedona thoroughknowledgeabouttherelationshipbetweenhistoricalbehaviorsandperformanceint h e future.Theresultofscoringisasinglescorewhichrepresentsabalancedsnapshotofaparticularapplicant'srisk.Apersonmayhaveweaknessesinacertainareabutgainstrengthsi n another.Thelinkbetweenallofthefactorsisexaminedandeveryfactorisgivenweightini t s relationshipw i t h others.A n
d e r s o n c o m m e n t s t h e credits c o r i n g u s e hass h i f t e d creditbusinessfromrelationshi
unsecuredlending.The factthat experiencehasbeenreplacedbydatahashinderedh u m a n judgementfromplayingmoreofarole.ThoughthefiveCsarestillapplied,byextractingthemaximumvaluefromavailablei n f o r m a t i o n , credits c o r i n g cancapturem u c h oft h e m Thisdoesn o t meant
h a t h u m a n j u d g e m e n t andcollateralt o t a l l y disappear;theyarethere, yetw i t h a le ss stresse
d role
Trang 22Underscoringapproach,borrowersarerankedaccording totheprobability thatthey
w i l l
belateintheirpaymentsordefault.Creditorstypicallysetupacut-
offscoreforacertainacceptablelevelofrisk.Forinstance,acreditormightestablishacut-offscoreforhisorherportfoliosothattheminimumoddsofrepaymentare25to1.Theapplicantswhosescoresarebelowthe cut-
offwillberejectedwhile thosewho areratedaboveitwillbe accepted.T h e levelofjustifiedriskcanvarybetweenlenders,portfoliosandmaychangefromtimetotime.T h e c u t -
o f f v a l u e c a n alsobea goods t a n d a r d ofp r i c i n g l o a n s inaccordancewiththedelinquentrisk
RelevanttoCSM,credit ratingmethodisalsoaddressedtoriskmanagement.However,
t hi s a p p r o a c h considersa widerr a n g e o ffactorst o c l a s s i f y corporate andinstitutionalcreditrisksintogrades.Thefollowingtableshouldmakeclearabouttheblurringb o u n d a r y betweenthesetwoapproaches
businessloansandi n s t i t u
t i o n a l loanswithininstituti ons
worldwidecompanies,fina ncialinstrumentsandSover eigns
numberofgrades(withinc o m
m o n frameacrossmajorr a t
i n g agencies) Users institutionitself institutionitself,supervisor lenders,investors,regulators Mainp
r d l y bep o s s i b l e f o r a ju dg em en t al d e c i s i o n procedureto weightand
Trang 23assessthatmuchcomplexity.Furthermore,aportionoftheavailabledataseemstocorrelateo r havenoreliableconnectionwithpaymentbehaviorinthefuture.Byselectingtheproperfactorsandanalyzingthecorrelation,CSMuserswouldbenefitbyminimizingtheinfluenceo f poorqualitydata.
ThemainfeaturethatdistinguishesmostCSMsiswhethertheydependonexhaustiveanalyticalstatisticso f realcreditexperiencet o ascertainwhichfactorsaret o b e p u t i n t o considerationaswellast h e weightthat eachonesh ou ld be assignedi n making finalcreditdecision.Byemployinga consistentdataset,a la rg e number ofstaffi n anorganizationcanreacht h e s a m e credit
d e c i s i o n Nonetheless,judgementalapproachesa n d C S M s m a y n o t alwaysproducesamedecisionswithrespecttosameapplicants.Underthecircumstances,itissuggestedthatsomefurtherexaminationsareneededinsteadofapprovingorrejectingthemd i r e c t l y (Dinh&Kleimeier,2007).Lastbutnotleast,aCSMisnotapanaceabutitshouldbetreatedasa refinementt o o l i n t h e processf o r creditgrantingi n ordert o formt h e ultimatecombinationo f b o t h humanbestpracticesandstatisticalapplications(VanG o o l , Verbeke,Sercu,&Baesens,2012)
incomehypothesiswhichpostulatest h a t spendinghabitsofpeopledonotchangeorarestableovertimewhenconsumerincomechanges.Keynesiantheoryrevealsthefactorshavingimpactonconsumptionareasfollows:
(1)individual'sreali n c o m e , (2)pastsavings,a n d (3)interestrate.However,o n e o f n o n
-i n c o m e determ-inantsthat-influencesMPC-isconsumercred-it.W-ithcred-itava-ilab-il-ity,consumersspendtheirincomemoreandotherwise,ifcreditiscostlyornoteasilyaffordable,consumerincomeisspentless.ItisnotedthatMPCismuchhigherforonewhoisnearertohis
orhercreditlimit(Gross&Souleles,2002)
Trang 24Concerningconsumptionhabits,Duesenberry(1949)revealsthatpeopleusuallyobservebehaviorandconsumptionpatternsfromtheirpeerstodecideontheir consumptionandsavings.Ifaconsumerfeelsanurgeforconspicuous consumptionasawhole,ahigherstandardo f c o
n s u m i n g actionm a y bedisplayed.Namingt h i s p h e n o m e n o n demonstrationeffect,heargu
esthatitpromotesunhappinesswithpresentconsumptionlevels,whichimpactso n savingsratesandt
h u s affectsmacroeconomicgrowth.C l o s e t o Duesenberry,N u r k s e (1957)addsthatthesociety'sexposuretonewgoodsorwaysoflivingbringsaboutunhappinesswithpreviouslyacceptedconsumptionpractices.Theconsumers'preferencefunctionsarenotindependentbutinterdependentas"peoplecomeintocontactwithsuperiorgoodsors u p e r i o r p a t t e r n s o f consumption,w i t h newarticleso r newwayso f m e e t i n g o l d wants."Hence,heconcludesthatthesepeople"areapttofeelafterawhileacertainrestlessnessanddissatisfaction.Theirknowledgei s extended,t h e i r imaginationstimulated;newd e s i r e s a r e aroused,t h e p r o p e n s i t y t o c o n s u m e i s s h i f t e d upward
"( p 5 9 ) A s a r e s u l t , creditdebtwillbeinvolvedinconsumptionifthereisanincomeshortageandconsumptionist o happen.Jappelli,Pischke,andSouleles(1998)provethathouseholdswithcreditcardsarebetterequippedtoconsumethanthosewithoutbankcards.TherealityisthatAmericanshavegrown comfortablewithconsumercreditasawayto smoothincomeover thelastfewdecades(Durkin,2000)
rationingissaidtohappenwhenpeoplewouldliketoborrowmoreataquotedinterestrateb u tcreditorspreventthemfromdoingso.6Intheirstudies,thoseauthorsanalyzethatbanksm a y rejectsomedebtorsbecauseofthetwocomponentsofasymmetricinformation.Thefirstcomponent–
a d v e r s e selection–
happenswhengoodb o r r ow e r s mightn o t t a k e th e l o a n ast h e y findinterestratetoohighwhileriskyborrowerscaneasilyaccepttotaketheloanatallcost.Thehighinterestratewillraisetheaverageriskofborrowers,possibly decreasingthelenders'profits.Thesecondcomponent–moralhazard–
occursaftertheloanhasbeengiven.Borrowersmightchangetheirbehaviors,i.e.toinvestinriskierprojectsbecausetheyarenotdealingw i t h t h e i r o w n funds.Ifs u c h r i s k y i n v e s t m e n t doesn o t payo f f , l e n d e r s cannot
5 In
mostothermarkets,suchasituationwillsimplyleadtoapriceincrease,whichmakesdemandequatesupply.
Trang 256 Another
notionofcreditrationingis,forexample,Bester(1985,p.850):"Creditrationingissaidtooccurwhen someborrowersreceivea
loanandothersdonot,althoughthelatterwouldacceptevenhigherinterestpaymentso r anincreaseinthecollateral."
Trang 26recovert h e f u n d s A s rationallenderscannotc o n t r o l allt h e behaviorso f t h e borrowersdirectly,theywillformulatethecontracttermsinamannerthatinducestheborrowerstotakeactionsforthe sakeof thelenders,aswellastoappeallow-riskborrowers.
Despiteinterestratea c t i n g asa s c r e e n i n g device f o r distinguishinggoodr i s k s frombadrisks,itisnotthe onlycontracttermthatisimportant.AccordingtoStiglitzandWeiss(1981),thecollateralamountdoesaffecttheborrowerintermsofbothbehaviorandd i s t r i b u t i o n Theoreticalliteratures h o w s t h r e e m a i n reasonsexplainingwhycollateralrequirementsarecommonlyquotedinloancontracts.Firstofall,collateralisrequiredbecausetherei s n o c e r t a i n t y t h a t
a borrower'sfuturei n c o m e w i l l b e asexpected.Ifanenforceableclaimagainstone'sfuturewealthandincomecouldbeissuedthentherewouldben o m o t i v a t i o n f o r hisorherbanktodemandsomekinds
ofassetsasaguarantee(Plaut,1985).Therefore,thebankwillresorttocollateraltoreduceloanlossincaseofdefault.Thisreasoni s intuitiveandindependentofasymmetricinformationbetweenthecreditor andthedebtor.Secondly,collateralmayreduceadverseselectionproblemastheborrowerownsbetterinformationthanthebankbeforeitslendingdecision.Suchprivateinformationcanresultincreditr a t i o n i n g s i n c e t h e banki s u n a b l e t o sett h e l o a n p r i c e a c c o r d i n g t o
i t s customer'sq u a l i t y (Stiglitz&Weiss,1981).Actingasasignalingdevice,collateralcanconveyborrower'svaluableinformationt o t h e lender,w h o w i l l t h e n screendebtorsbyofferingth
e
alternativebetweenalow-pricesecuredloanandahigh-priceunsecuredone.Ahigh-qualityborrowertendst o c h o o s e collateralt o signalh i s o r herq u a l i t y andt h u s securesa lowerinterestratef o r t h e l o a n (Bester,1985).Finally,collateralc a n helpt o reducemoralh a z a r d problemsoncet h e m o n e y h a s beendisbursed,byd e t e r r i n g t h e borrower'sm o t i v a t i o n s t
o i n v e s t t h e fundinriskierprojectsorto makelessefforttobringthefinancedprojecttosuccess(Boot,Thakor,&Udell,1991).Usingcollateral,indeed,thebankisabletoalignitsdebtor'sinterestwith its ownsincethedebtorwillendureagreaterloss ifhisdefaultshould happen
2.4 Reviewsofempiricalstudies
2.4.1 Defaultpredictorsinmarketsforcreditcardsandinstantloans
Manyo f t h e p r e v i o u s empiricalstudieso n r e t a i l credit,e s p e c i a l l y c o n s u m e rcreditmarket,focusonmost traditionall oa ns whichdifferfroml oa ns f o r credit cardsandinstantl o a n s inthe following keyrespects.W i t h traditionalloans, loan amountsarepredeterminedandpaymentschedulesarefixed;whileincreditcardandinstantloanmarket,theactualloanamou
Trang 27ntsareatt h e clientele'sdiscretionaftera f i x e d creditl i n e i s m a d e available.Debtrepaymentf
o r t r a d i t i o n a l l o a n s i s oftenpaidi n installments,whereasa creditc a r d h o l d e r
Trang 28flexiblypaysbackhisdebtintermsofarequiredmonthlyrepaymentasacertainpercentageo f theoutstandingbalance.Finally,contrarytomanytraditionalloans,creditcardandinstantl o a n customersmaybegrantedw i t h a s m a l l e r amountoff u n d s w i t h o u t a n y s t r i c t requirementsoncollateral.
JacobsonandRoszbach(2003)d o researcho n c r e d i t
-s c o r i n g i n whichtheyrecommenda probitapproacht o e v a l u a t e p o r t f o l i o creditr i -s k Int h e i r study,t h e d a t a i s collectedfromnotonlyapprovedloansbutalsorejectedapplicantsaswell.Inthisway,theyj u s t i f y thattheirmodelsdonotsufferfromtheso-calledsample-selectionbiaswhichc o m m o n l y existsintheliterature.Thedatasetconsistsof13,338loanapplicantsfromamainl e n d i n g institutioninSwedenfromSeptember1994toAugust1995.Atfirst,57variablesareobservedbutonly16arecultivated.Thereasonwhymostofthevariablesareignoredisthatt h o s e variableshavelittleexplanatorypowerortheyarebetterexplainedbyothervariables.T h e empiricalevidencerevealsthatage,marital status,changeinyearlyincomeandcollateral-
freecreditamountaresignificantlyinfluentialinthedefault.Surprisingly,loansizes h o w s nosignificantimpactonthedefaultandhigherincometurnsouttoconnectwithhigherdefaultrisk
Agarwal,Chomsisengphet,andLiu(2011)e m p l o y anothert e c h n i q u e t o s t u d y t h
e influenceo f
individual-social-capitalr o l e o n i n d i v i d u a l defaultandbankruptcyo u t c o m e s T h e y useamonthlysetofpaneldatacoveringatleast170,000cardholdersintheU.S.fromJ a n u a r y 1997toJune2000andconductthestudywithCoxproportionalhazardmodel.Withobservationsofallborrowers'defaultandbankruptcyfilingstatus,theycouldfindthosethataffectt h e defaultarefinancialdistressfactors(e.g.r i s k i n e s s , income,debt,spendingandwealth),economicconditionsandlegalenvironmentaswellassocio-
demographiccharacteristics(e.g.age,statusofmarriageandhomeownership).Aftercontrollingforfinancialdistressfactors,economicconditionsandlegalenvironment,the resultsrevealthatcardholdersaremorelikelytodefaultiftheymigratefromtheplaceofbirth.Regardingage,t h e riskrisesbutthenfallsandgroupsthathavethesmallestbankruptcyriskaretheyoungest( 3 0 yearsoldoryounger)andtheoldest(60orolder).Anotherfindingisthatborrowerswhoaremarriedandownahousearerespectively17%and24%lessprobabletofallintoarrears,and25%
and32%lessinclined tofile for bankruptcy
DifferentfromtheabovestudiesAutio,Wilska,Kaartinen,andLähteenmaa(2009)don o t a
p p l y anyregressiont o researcht h e p o s s i b i l i t y ofdefaultb u t theyanalyzet h e demographicbehaviorsoftakenloans.Theycarryoutacomprehensiveinvestigationontheu s e ofinstantloansinFinlandinthecontextoffinancialcrisis.Thesampledataconsistedof
Trang 291,610respondentsamong1,951youngadultsfilling outquestionnaireswhichinclude demographicprofilesasgender,age,income,householdstructure,occupationandemploymentstatus.Theintervieweesarealsodemandedtorevealwhichkindoftheircredit:s m a l l loans,studentloans,creditcardsormortgages.Basedonthecollecteddata,theresearchersexaminethepeople'sattitudestowardsborrowing.Theresultsuncoverthatyoungpeopleoftheages18to23usesmallinstantloansmorethanthe24-to-29-year-
oldones.Ont h e otherhand,thelattergrouphasmoreuseofconsumercreditastheyhavehigheroccupationalstatusandincome.Genderdoesnotappeartoaffectthenumberofloanstaken,b u t income,occupationalstatus andhouseholdstructuredo
2.4.2 Defaultpredictorsinmarketsforautomobiles,mortgagesandrealpropert
yconstruction
Asautomobiles7arethemostcommonconsumptiongoodsthatAmericansoftenpurchaseo n credit,Agarwal,A m b r o s e , andChomsisengphet(2008)s h o w t h e i r interesti n investigatingt h
e performanceo f automobilel o a n s i n termso f defaultr i s k andp r e p a y m e n t risk.8T h em a t u r i
t i e s a r e f o u r andf i v e yearsa n d t h e l o a n performancei s observedf r o m J a n u a r y 1 9
9 8 t o March2 0 0 3 i n a largefinancialinstitutioni n t h e NortheasternU S T h e y conductacompeting-
riskmodelwithadatasetof20,466directpersonalloans9f o rpurchaseso f newandusedautomobiles.Theirmainfindingsareasfollows.Itismorelikelytodefaulto n aloanforausedcarwhereasthereishigherlikelihoodofprepaymentonaloanforanewcar.Surprisingly,a c u s t o m e r w i t h lowercreditscoreshasl o w e r p r o b a b i l i t y ofdefaultb u t higherlikelihoodo f prepayment.A s expected,a r i s e i n t h e loan-to-
valueratioraisest h e p r o b a b i l i t y o f defaulta n d decreasest h e likelihoodo f prepayment.Incomehasa p o s i t i v e impacto n t h e p r e p a y m e n t w h i l e unemploymenthasa n e g a t
i v e effecto n t h e l o a n performance.Paradoxically,adecreaseinthebasicratewillincreaseboththeprobabilityofdefaultandprepayment.Andmostinterestingly,borrowersformostluxuriouscarsinclineto
repaytheloansinadvancewhilethosewhoborrowtofinancemosteconomicalcarstendtoperformtheloanswell
Concerningmortgages,PeterandPeter(2011)u s e i n c o m e ando t h e r t w e l v e factorsw i
t h 3 , 4 3 1 WesternAustralianhouseholdsto estimate thelikelihoodofloandefault.Theyaim
7 Automobiles
meancarsandlighttrucks.Besidesautomobiles,othertermssuchasautos,carsandvehiclescanb e used interchangeable.
Trang 308 Prepayment
riskoccurswhenautopurchaserspayofftheloansearly,whichreducesorviolatesthecreditors'f l o w ofinterestpayments.
9 Agarwal
etal.(2008,p.18)Agarwaletal.makeitclearthat"directloansareissueddirectlytotheborrower,
andindirectloansareissuedthroughthedealer."Inthelattercase,financialinstitutionshaveagreementswitha u t o
m o b i l e dealershipstograntloansatfixedinterestrates.
Trang 31toformt h e relationshipbetweenh o m e o w n e r s ' r i s k defaultandt h e i r characteristicsw i t h a logisticregression.Thestatisticsimplythatonaverage93%ofthehouseholdsarepunctual.T h e regressionresultsrevealt h a t i n c o m e i s a h i g h l y predictivevariable,i e loweri n c o m e levelisoneofthemainfactorsthatsendthemortgagorstodefault.Another notablycriticalfactorisloan-to-valueratiowhichmeansthelikelihoodofdefaultwouldincreasewithhigherloan-to-
valueratio.Onemorefindingisthatinallprobabilitythedefaultwouldbehigherift h e heado
f t h e f a m i l y i s l e s s educated,youngeranddivorcedi n comparisonw i t h o t h e r households.Theageoftheheadofhouseholdsisalsoagoodindicatorwhichsignalsthattheperformanceofmortgagerepaymentstendstobenegativelyimpactedbyyoungerhouseholds
Otherindicators,forinstance,employmentstatus,migrantstatusandmacroeconomicfactor10shownosignificance.Thedevelopedmodelisprovedtobeausefultoolthatbenefitsprivatelenders,p o l i c y m a k e r s andgovernmentinassessingt h e defaultriskanddevelopingt h e appropriatestrategiestominimizethem
Asthereh a v e b e e n m a n y studieso n p r e d i c t i n g defaulti n t h e d e v e l o p e d countries,KočendaandVojtek(2011)carryoutaresearchinaEuropeanemergingmarket.TheygainaccesstoadatasetofaCzechbankwhichspecializesingrantingpersonalloansofsmallandm e d i u
m
sizeinthefieldofrealestatereconstructionandpurchase.Thedatacontainssocio-demographiccharacteristicsaswellasotherinformationon3,043individualswhogotloansbetween1999and2006.TheirmodelsaretestedwithlogisticregressionandCART11analysis
afterinformationvaluesofvariablecategoriesarecalculated.Theresultisthatsixoutof21variablescanhaveabilityt o discriminatebetweengoodandbadclients.Theya r e alsovariablesthathavehighinformationvalues.Itisnoticeablethatbothapproachescanproducesimilarefficiencyanddetectthesamefinancialfactorsandsocio-
demographicfactorsasthek e y predictorso f l o a n performance.Clientsw i t h higheramounto f
o w n resourcesreflecta d i s t i n c t l y lower defaultprobability.Largerl o a n s arerecognizeda
sr i s k i e r debts.Loansf o r p r o p e r t y renovationtendtoexposetomore
riskthatthoseforrealestatepurchases.Likeotherstudies'finding,higheducatedcustomerscanbemucheasierinrepayingtheirdebts.Clientsw i t h longerrelationshipw i t h t h e bankarel e s s r i s
k y t h a n t h o s e w i t h shortertime.A l s o , marriedclientsshowsignsofmoresafetytograntloanscomparedtothosewithnospouse.T h e twoauthorsalsomanagetobuildawell-
performedmodelexcludingthemostsignificantfactor–
client'sow n resources.Bythisway,t h e y re- confirmed t h e p r e d i c t i v e poweroft h e demographicvariables
Trang 332.4.3 Defaultpredictorsinmarketsforindividualloans
Someauthorsdonotnarrowdowntheirexperimentstoaspecificloanpurposeliketheaforementionedliteratureb u t incorporateallp u r p o s e s i n t o t h e samem o d e l Forinstance,ÖzdemirandBoran( 2 0 0 4 ) e m p l o y a l o g i s t i c b i n a r y regressiont o evaluatet h e relationshipbetweenconsumerloans'defaultriskandtheirdemographicandfinancialvariables.Theyuset h e datasetof500customer recordsmostly involvingindividualsupportloans, homeloansandcarloansprovidedbyanIstanbulprivatebankfrom1999to2001.Interestingly,theyfindn o notablerelationshipbetweendemographicvariablessuchassex,ageandoccupationsectorandthedefaultrisk.Theonlydemographicvariablethatimpactsonthecreditperformanceisresidentialstatus.Meanwhile,thefinancialvariables such asinterestrateandmaturity havea b i l i t y topredicttheoutcomes.Thelongerdurationorthehigherinterestrate,themoreriskf o r customersn o t p a y i n g b
a c k t h e i r debtsi n t i m e ÖzdemirandBoranconcludefinancialvariablesh a v e m o r e significanteffectso n t h e customers'performancet h a n demographicvariablesd o T h e f i n d i n g s u g
g e s t s t h a t b a n k e r s s h o u l d p u t appropriatefocuso n financialvariablesto
minimizedefaultrisk
InVietnam,Vuong,Dao,Nguyen,Tran,andLe(2006)becomethefirsttoexplorethel i n k betweenl o a n performanceandborrowercharacteristics.1 6 featureso f customersaretakeni n t o consideration;m o s t o f t h e m aresocial-
demographicalvariables.T h e dataseti s obtainedfromT e c h c o m b a n k ,12whichcovers1 , 7 2 7
i n d i v i d u a l customerrecordsi n c l u d i n g 1 , 3 7 4
goodloansand353non-performingloans.Withlogisticregression,theirmodelproducesahighlypredictiveaccuracyof99%.Theauthorsthenofferaclassificationsystem
ofC S M basedo n t h e o u t c o m e o f performanceprobability.Forexample,goodcustomersclassi
2005periodcoveringawidevarietyofloanpurposesfrombusinessloans,mortgagesandhomeloa
Trang 34ns,mobile assetfinancingtogeneralcredit( l i v i n g e x p e n s e s o r consumptionw i t h o u t collateral)andcreditc a r d facilities.T h e y
12 Techcombank
stockBank,whichwasestablishedonS e p t e m b e r 27th,1993andtheHeadOfficeisinHanoi.
Trang 35standsforVietnamTechnologicalandCommercialJoint-initiallyrelyontheloanofficer'sexpertknowledgetoname22pertinentvariables.Afterthat,t h e forwardstepwisem e t h o d h e l p s t h e m choose1 6 o u t o f t h e first2 2 i n t h e m o d e l W i t h logisticregressionagain,theydevelopaflexiblemethodthatisconstructedfromthestandardsoftransactionallending,yetrelationshiplendingisalsoleftroom
for.Theyfindthatregion,residentialstatus,maritalstatus,collateraltypeandeducationarenoteffectivepredictors.Them o s t importantvariablesaret i m e w i t h bank,bankaccountfollowedbygender,loannumberandduration.TheirCSMissuggestedtoberegularlyu p d a t e d toresponsetoeconomicchanges
s n o t sufficient,butt h e covariancerisk13o rt h e defaultbetas h o u l d bealsotakenintoaccount.Intheirstudy,MustoandSoulelesaccessarichandunique
sourceofcreditdatafromExperian,oneoftheleadingU.S.creditbureaus.Thepaneldatasetcontains1 0 0 , 0 0 0 r a n d o m sampleso f m o n t h l y customersbetweenMarch1 9 9 7 andMarch2 0 0 3 Therearedifferentcategoriesofgrantedloans,suchascreditcards,automobileloans,mortgages,etc.Themajorresultrevealsthatthereissignificantheterogeneityamongcustomersinthedefaultbeta.Highcovariance-riskconsumerstendtogetlowcreditscores,
i.e.highdefaultlikelihood.Thereisapositivecorrelationbetweenthesumofmoneyreceivedbyborrowersandtheircreditscoresandanegativecorrelationbetweenthefundlenttothemandt h e covariancer i s k Thosew h o e x p o s e t o highcovariancer i s k i n c l u d e t h e young,t h e single,h o m e renters,l o w e r - i n c o m e c o n s u m e r s , andr e s i d e n t s i n regionsw i t h lowerh e a l t h -
insurancecoveragebut ahigherdivorcerate
2.5 Chaptersummary
2.5.1 Empiricalliteraturesummary
Thefollowingtablesummarizesandcomparesthecommonvariablesusedinpreviousempiricalliteraturet o p r e d i c t creditd e f a u l t T h e t a b l e mayn o t expresse x a c t l y t h e s a m evariablesemployedbyt h e authorsb u t i t meanst o reviewt h e m o s t s i g n i f i c a n t ones.T h evariablesa r e dividedintot w o groups:
Trang 36( 1 ) Borrowercharacteristicsand( 2 ) L o a n characteristics.Itisnoteworthythatdividingandn
amingsuchcharacteristicscanvary
13 See
Lusardi's(2006)commentonhowtocalculatethecovariancerisk.
Trang 37betweenauthors.Forinstance,ÖzdemirandBoran(2004)nameDemographiccharacteristicsv s Financialcharacteristics,KočendaandVojtek (2011)sortSocio-
demographicvariablesfromBank-clientrelationshipvariables,VanGooletal.
(2012)useBorrowercharacteristicsandL o a n characteristics.O n t h e contrary,s o m e authorsd
o n o t groupt h e variablesatall(Jacobson&Roszbach,2003;Vuongetal.,2006;Dinh&Kleimeier,2007).Inthisstudy,webaseonVanGooletal (2012)to classifythevariablesintoborrowerandloancharacteristics
Dinh&Kl eimeier( 2
Trang 38Maturity/Loanduration ** **
regression 13,338loan
Logitr eg r
e s s i o n 500
Logitr e g r
e s s i o n 1,727retail
Logitr e g r e
s s i o n 56,037retail
Sweden
consumer loansin Istanbul
loansfrom Techcombank, Vietnam
loansin
V i et n a m
Trang 39Borrowercharacteristics
Agarwal,Ambro se&Chomsiseng phet(2008) Autioetal.,(2009)
Kočenda&
V o j t e k (2011)
Peter
&Peter(
2011)
Agarwal,Chomsi sengphet
Questionnaire
&Descriptive statistics 1,610
Logitregre ssion,CA
R T 3,043real
Logitregre ssion 1,303
Coxproportio nalhazardmo del 170,793
Samplesize autoloansin
Northeastern U.S.
young adultsin Finland
estateloansi nCzech
homebuyers inWestern Australia
cardholders inU.S.
Trang 40N.Smeansnotsignificant;
*,** and***meansignificancelevelat10%,5%and1%respectively;