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Dynamic Inte r pretation of Emerging Systemic Risks. Kathleen W eiss Hanl e y 1 and Ge r ard Hoberg 2 1 Lehigh Uni v ersity 2 Uni v ersity of Southe r n Cali f o r nia MFM Con f erence March 2017. Special Thanks: National Science F oundation.
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DynamicInterpretationof EmergingSystemicRisks KathleenWeiss Hanley1andGerardHoberg2 1Lehigh University 2University of Southern California MFMConference March2017 Dynamic Emerging Systemic Risks
SpecialThanks:NationalScienceFoundation This project wasmadefeasible throughNSFgrant #1449578 Grantwas funded through CIFRAM program.A specialcall for projects that might benefit the Office of Financial Research(OFR). We still know little aboutcrises build, or how to predict and preemptthem.Hugeramifications if progresscanbemade. Dynamic Emerging Systemic Risks
SpecialThanks:metaHeuristica Analytics madepossible usingmetaHeuristica Software Dynamic Emerging Systemic Risks
HypothesizedInformationalEnvironment Suppose3 states of the world: Non-crisis periods.No informationproduction predicted. Transition periods (wepropose):Some info production. Crisis periods.Extensive information production. 1 2 3 CentralPremise:Informationproducers in transition period will tradeand their actionsmightbedetectable. Implication:Interpretable earlywarningsystempossible. Dynamic Emerging Systemic Risks
TheoreticalMotivation Detecting informationaboutbanks is challenging. Efficient debtcontracting “requires that noagent finds it profitable to produce costly informationabout the bank’s loans.”[Dang,Gorton, Holstrom,andOrdonez (2016)] Reasons:Costly information,loan size incentives ... Implication:Optimalbankopacity.Expectnosignal in normaltimes. Implication:Evenintransitionperiods,expect weaksignal. Need strongpowertoovercomenoise.Usebigdata. Dynamic Emerging Systemic Risks
Propertiesofidealpredictivesystemicriskmodel Automatedand free of researcher bias. Interpretable without ambiguity. Can detect risks dynamically that did not appear in earlier periods. Permits flexibility to delvedeeper into topics of interest. Detects risk factors well in advance of panics. Ourapproachmakes significant headwayon all 5dimensions. Dynamic Emerging Systemic Risks
Methods:SeePaperforDetails RESULT:A firm-yearpaneldatabase with 18thematicscoresfor eachobservation. Dynamic Emerging Systemic Risks
MostNovelInnovation:SemanticVectorAnalysis LDAalone is popularbut difficult to interpret.Yet it can pickup “systemic” content. AsecondstageSVAmodel solves the interpretability problem. SeeMikolov, Chen,Corrado, andDean(2013)and Mikolov, Sutskever, Chen,Corrado, andDean (2013). We arenotaware ofotherfinancepapers using thistechnology. Dynamic Emerging Systemic Risks
Semanticthemes Important: Selectedthemesmust bepresent in verbal LDAfactor analysis (i.e., havea strong verbal factor structure in risk disclosures).Ensures only systematically relevant risks make the list. Dynamic Emerging Systemic Risks
ExamplesofSemanticVectors Mortgage Risk Capital Requirements Dynamic Emerging Systemic Risks
ResultofComputationalLinguistics:Largebank-year paneldatabase Note:Thisdatabase is used to construct a network of bank pairwise commonexposures. Dynamic Emerging Systemic Risks
StockReturnCovarianceMatrixisStochastic Question:Canweuse big data to examinewhenperturbation is likely systemicrisk? Dynamic Emerging Systemic Risks
DoesRiskFactorNetworkExplainCovarianceMatrix Network? Note:RHS network indicates, verbal factor byverbal factor, do banks i and j disclose the samerisks with similar intensity? Note:Verbal factors identified usingLDA,and specifically from bankrisks.Hence only systemically important risks are “eligible” to bepart of network. Dynamic Emerging Systemic Risks
Ouremergingriskmodelbasedonpairwise covariance Run regression onceperquarter.Oneobservation is a bank-pair (iandj). Dependentvariable is returncovariance of iandj measuredusing daily returns. Independentvariable of interest is semantictheme of pair defined as the productSi,j=SiSj Xare control variables including pairwise products:size, age, call report data, and industry. Covariancei,j,t=α0+γXi,j,t+εi,j,t, (1) Covariancei,j,t=α0+β1Si,j,t,1+β2Si,j,t,2+β3Si,j,t,3+...+βTSi,j,t,18 (2) +γXi,j,t+εi,j,t, Dynamic Emerging Systemic Risks
Ouremergingriskmodel II Covariancei,j,t=α0+β1Si,j,t,1+β2Si,j,t,2+β3Si,j,t,3+...+βTSi,j,t,18 (3) +γXi,j,t+εi,j,t, Goal:decompose the R2of this model into parts related to (A) accountingvariables, and (B) textual risk disclosures. WhenR2attributed to risk factors increases, ared flag IS RAISED. Dynamically interpret themesfor channelsdriving increased R2. Dynamic Emerging Systemic Risks
DataSources Weconsiderbanksas identified by firmshaving SICcodes from 6000 to 6199.Weexclude all other firms. CRSP (stock returns), Compustat(accountingvariables). FDICFailures andAssistanceTransactions List.We also consider VIX data. Call Reports for bank-specific accounting data. metaHeuristica is used to extract risk factor discussions from bank10-Ksfrom1997 to 2014. We require the firm to haveamachinereadable 10-K, with somenon-emptydiscussion of risk factors, to be included. Dynamic Emerging Systemic Risks
AggregateSystemicRiskSignal OurMain Result:t-statistics of R2due to textual factors 14 12 10 8 6 4 2 0 19980119990120000120010120020120030120040120050120060120070120080120090120100120110120120120130120140 -2 t-statistic Dynamic Emerging Systemic Risks
Summaryof2008MajorRisks(t-stats) Dynamic Emerging Systemic Risks
Drill-downextendedmodel Thesesemanticthemeswerechosenfor moredepthon marketable securities theme Dynamic Emerging Systemic Risks
Summaryof2015MajorRisks(t-stats) Dynamic Emerging Systemic Risks
Extenddatato4Q2016«NEW» Dynamic Emerging Systemic Risks
Extenddatato4Q2016«NEW»II Dynamic Emerging Systemic Risks
CrossSection:Individualbankexposuretoemergingrisk DefineEmergingRiskExposure:averagequarterly predicted covariancebankihas with all other banksjusing the main covariancemodel in Equation(3) Doesemergingrisk exposure predict: Bank’s quarterly stock return from 9/2008 to 3/2009 and 12/2015 to 2/2016 Dummy variable indicating whether the givenbankfailed in 3 years after Lehmanbankruptcy Dynamic Emerging Systemic Risks
Predictingpost-2008crisisreturns(9/2008-12/2012) Dynamic Emerging Systemic Risks
Predictingcurrentperiodreturns(12/2015-2/2016) Dynamic Emerging Systemic Risks
Predictingbankfailures Dynamic Emerging Systemic Risks
Conclusions • Weproposeadynamicmodel of emergingsystemicrisks basedoncomputational linguistic analysis of • financialfirmdisclosuresandreturncovariances. • Benefits of model: • Provides little or no signal in “normal times”. • Provides aggregate measure of trading on systemic risks. When systemic risk is building, produces interpretable information about specific channels. • Model is dynamicand reveals risks researcher might be unaware of.Yet SVA also allows researcher to drill down. • Suggestsinterpretable early warningsystemis possible. • AlsosuggestsSEC’srisk factor disclosure program is valuable (not apriori clear fromexisting work). Dynamic Emerging Systemic Risks