ContentslistsavailableatScienceDirect
Journal
of
Economic
Behavior
&
Organization
jo u r n al ho me p ag e :ww w . e l s e v i e r . c o m / l o c a t e / j e b o
Auditing,
disclosure,
and
verification
in
decentralized
decision
problems
夽
Luca
Anderlini
a,∗,
Dino
Gerardi
b,
Roger
Lagunoff
aaGeorgetownUniversity,USA bCollegioCarloAlberto,Italy
a
r
t
i
c
l
e
i
n
f
o
Articlehistory:
Received5February2016
Receivedinrevisedform30August2016 Accepted9September2016
Availableonline30September2016 JELclassification: C73 D63 D72 D74 H11 Keywords: Auditing Disclosure Agencybias Ideologicalbias
a
b
s
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Westudytherelativeperformanceofdisclosureandauditingindecentralizedinstitutions. Weconsidertheinformationtransmissionproblembetweentwodecisionmakerswhotake actionsinsequenceattwodecisiondates.Thefirstdecisionmakerhasprivateinformation aboutastateofnaturethatisrelevantforbothdecisions,andsendsamessagetothe second.Theseconddecisionmakercancommittoonlyobservethemessage(disclosure),or canretaintheoptiontoobservetheactionofthefirstdecisionmaker(auditing)or,atsome cost,toverifythestate.Inequilibrium,stateverificationwillneveroccurandthesecond decisionmakereffectivelychoosesbetweenauditinganddisclosure.
Whenthemisalignmentinpreferencesreflectsanagencybias–abiasinadecision maker’sownactionrelativetothatoftheother–thentheseconddecisionmakerchooses toauditinequilibrium.Whenthemisalignmentinpreferencesreflectsanideologicalbias –onedecisionmakerprefersallactionstobebiasedrelativetotheotherdecisionmaker –then,foralargeenoughmisalignment,theseconddecisionmakerchoosesdisclosurein equilibrium.Ourresultsindicatethattheabilitytocommittoforegotheaudithasvaluein thelattercase.
©2016ElsevierB.V.Allrightsreserved.
1. Introduction
Inanyongoingorganizationorsocietytherearetwoprimarywaysinwhichinformationisrevealed.Oneisdisclosure– transmissionofinformationbytheinformedpartiestouninformedreceivers.1Disclosureconsistsofallformsof
manufac-turedtransmissionincludingoralandwritten(files,archives,etc.)communication.Theactofdisclosinginformationmayor maynotbeobligatory.2Thekeyisthatitscontentcanbefreelychosenbytheinformedsender.
夽 Apreviousdraftwascirculatedunderthetitle:“DoActionsSpeakLouderthanWords?Auditing,Disclosure,andVerificationinOrganizations.”Wewish tothankTomGresik,anAssociateEditor,andtwoanonymousrefereesfortheirhelpfulcommentsandsuggestions.Wealsothankseminarparticipants atJohnsHopkins,NorthCarolina,PUC(Chile),HKUST,theIADB,UniversidadAlbertoHurtado,Vanderbilt,andtheMidwestTheoryMeetingsatIndiana University.AllthreeauthorsaregratefultotheNationalScienceFoundationforfinancialsupport(GrantSES-0617789).Someoftheworkwascarriedout whileLucaAnderliniwasvisitingEIEFinRome.Hegratefullyacknowledgestheirgeneroushospitality.
∗ Correspondingauthorat:GeorgetownUniversity,37thandOStreetsNW,Washington,DC20057,USA. E-mailaddress:luca@anderlini.net(L.Anderlini).
1Noticethatwhileweusethetermdisclosureassynonymouswithcheaptalk,ithasalsobeenusedintheliteratureasrevelationofinformationthatis verifiablebythereceiver.
2Recordkeepingrequirementsinfirmsfitthisdefinition.
http://dx.doi.org/10.1016/j.jebo.2016.09.002
Theotherformofrevelationisdiscretionaryauditing–theattemptbytheuninformedpartytoinvestigateorverifythe informationinsomefashion.AuditingmaytakeplaceundertheguiseofaformalprocessorinstitutionsuchastheGeneral AccountabilityOfficeintheU.S.government,oritmaytaketheformofaninformalmonitoringarrangementinacollective actionproblem.
Thispaperstudiestherelativeperformanceofdisclosureandauditingindecentralizeddecisionsettings.Inthesesettings, itisoftendecisionmakersthemselveswhomakechoicesaboutwhichofthetwoinformationchannelsisbest.
Infirms,forinstance,differentmanagersarepromotedtokeydecision-makingpostsovertime.Itisstandardpractice foracurrentmanagerialteamwithinside knowledgetoprovideadetailedprospectusofthecompany’soverallhealth periodically.Evenso,itspolicies,expenditures,andacquisitionsmayalsobeauditedtoprovidesomeexternalverification toshareholdersandsubsequentgenerationsofmanagers.
Politicalsystemsoperateinmuchthesameway.Rivalpoliticalpartiesvieforpowerovertime.Arulingpoliticalparty holdssomeinsideinformation(forinstance,knowledgeoftheeffectsofaparticularregulation)andisrequiredtodisclose whatitknowsorobserves.Arivalpartyeventuallyreachespowerandmustthenchoosetoeitheraccepttheoutgoingparty’s wordsorinsteadinvestigatetheoutgoingparty’spoliciesanddecisions.
Otherexamplesincludecommonpoolproblemsinwhichuserswithcurrentaccesstotheresourcemustdecideonthe bestmeanstoextractinformationaboutthestockfromearlierusers,andregulatoryenvironmentsinwhichregulatorsmust decideonhowstructurereportingrequirements.
Withtheseexamplesinmind,wepositatwo-periodpolicysettingmodelthatattemptstocapturesomeofthekeytrade offsinthechoiceoftransmissionmechanism.Weassumethatthepolicyateachdateischosenbyadistinctdecisionmaker. Disclosureisassumedtotaketheextremeformofcheaptalk,whileauditingtakestheextremeformofbeingabletodirectly observetheactionstakenbyothers.Inperiod1,theinitialdecisionmaker–DM1(the“sender”)–choosesanaction(a “policy”)andacheap-talkmessageafterprivatelyobservingtherealizationofanunderlyingstatevariablethataffectsthe preferencesofbothDMs.Inperiod2,theseconddecisionmaker–DM2(the“receiver”)–choosesapolicy.
ThechoicesofpossibleinformationchannelsopentoDM2areasfollows.Shecanchoosetocommittoonlyobserve DM1’smessagebeforeDM1takesanyactionorsendshismessage.Werefertothisasacommitmenttorelyondisclosure. ThedecisionbyDM2ofwhetherornottorelyondisclosureisobservedbyDM1whothenchooseshispolicy.IfDM2chooses nottocommit,sheretainstheoptiontoobserveDM1’saction,whichwerefertoasauditing,ordirectlyverifythestate– referredtosimplyasverification.Forsimplicity,auditingisassumedtobecostlessandstateverificationhasavanishing small(lexicographic)cost.3Onceperiod2arrives,DM2isinchargeoftheorganizationandheractionisthentaken.
Misalignedpreferencesbetweenthetwotemporallyseparatedagents(e.g.,twomanagerialteams,twopoliticalparties, ortworesourceusers)distortincentivesawayfromprofit-maximizing,orwelfaremaximizingpolicies.Theeffectofthis misalignmenthereisthatfulldisclosuredoesnotoccur.Inthissenseoursetupisrelatedtotheclassiccheaptalkenvironment inCrawfordandSobel(1982)(henceforth“CS”).TheirsenderisourDM1,whileDM2istheirreceiver.UnlikeintheCS environment,policydecisionsherearemadebybothplayersandthereceivermaychoosetoauditbeforetakingherown decision.
Weaskwhendisclosurewillbeused,andwheninsteadorganizationsrelyonauditing,orevenverification,inequilibrium. Theanswerisnuancedanddependsontheparticularcharacteristicsoftheorganization.
Ourfirstresult,Proposition1,showsthatDM2willneverchoosethedirectverificationoptioninequilibrium.Intuitively, ifDM1expectsthestatetobeverifieddirectly,hewouldchoosehismostpreferredfirstperiodpolicytailoredtothestate. Butbecausehispolicywouldfullyrevealthestate,theuninformedDM2wouldthenswitchtothelesscostlypolicyaudit. Thisisshowninanypurestrategyequilibrium,butwelaterverifythatitholdsgenerically(inthelevelofbias/misalignment) formixedstrategyequilibriaaswell.4
AsaresultofProposition1,DM2’seffectivechoiceisbetween“words”(disclosure)andthe“actions”(policyaudit)ofher predecessor,DM1.Thechoicebetweenwordsandactionsultimatelydependsonthewedgeinpreferencesbetweenthetwo parties.Werefertothismisalignmentasthe“bias”(followingCS)andexaminethefollowingtwocanonicalcases.
Inthecaseofideologicalbias,thefirstdecisionmakerDM1alwayspreferssystematicallyhigherpoliciesthanDM2, regardlessofwhichpartychoosesorwhichperiodthechoiceismade.Theideologicalbiasesarisenaturallyinpoliticswhere competitionbetweenideologicallydifferentiatedpartiestakesplace.
Ideologicalbiascontrastswiththecaseofagencybiaswherebytheactivedecisionmakerprefersahigher(orlower)policy thanhiscounterpart,thepassivestakeholder.ThismeansthatDM1(DM2)prefers,say,ahigheractioninperiod1(period2) thanDM2(DM1).Arguably,manyprivatefirmsconformtothiscasesincethefuturedecisionmaker(DM2)isoftenselected internallyfromexistingmanagement,andthepreviousmanagerholdsstockoptionsthatincentivizeshisfuturedecisions. Thesetwoformsofbiasgiverisetoquitedifferenttransmissionprotocols.Withagencybias,DM2willgenerallychoosea policyaudit.However,underlargeenoughideologicalbias,DM2willcommitinadvancetouseonlythedisclosedinformation. Inotherwords,wefindthatunderideologicalbias,theuninformedpartywillrelysolelyontheinformedparty’scheaptalk inequilibriumandthusforegoallsubsequentauditandstateverificationopportunities.
3 Theassumptionofcostlesspolicyauditsisshowntobewithoutlossofgenerality.Alltheresultsgothroughifauditscostsaresmall.Ourmainresult (Proposition3(i))goesthroughwitharbitraryauditingcosts.SeeSection5foradetaileddiscussion.
Togainsomeintuitionfortheseresults, weobservefirstthatequilibriainwhichDM2reliesonlyonmessageswill resemblethoseinstandardcheaptalkmodels(e.g.CS).Thatis,whileDM1can,inprinciple,reportfalseinformation,she choosesnottoinequilibrium.Instead,thesender’smessageispartially,butnotfully,informative.Thelackoffulldisclosure isofcoursebadforDM2.Incontrast,whenapolicyauditoccursinequilibrium,DM1chooseshisactiontakingintoaccount bothitsdirectpayoffeffect,drivenbythebias,anditssignalingvaluedrivenbyDM1’spreferencesoverDM2’sactioninthe secondperiod.
Whenthewedgebetweenpreferencestakestheformofanagencybias,thesetwoeffectsroughlyoffsetoneanother, therebymitigatingtheeffectofthesender’sbias.However,inthecaseofideologicalbias,thedirectpayoffeffectandthe signalingvaluereinforceoneanother;bothinduceactionsthataretoolargefortherecipient.Ifthereinforcedeffectofthe biasislargeenough,theauditbecomesundesirableforDM2whothenavoidsitinequilibrium.Infact,weshowthatforgoing theauditinganddirectverificationoptionsinfavorofdisclosureisnotjustpreferablefortherecipientunderideological bias,butitisParetoimprovingforallpartiesiftheideologicalbiasislargeenough.
AcriticalpartoftheargumentisthatDM2cancommitinadvancetoforegooratleastlimitthescopeofadiscretionary audit.Tosomeextent,thiscanbeviewedasasimplifyingassumptionsincethecommitmenttoforegoauditingisshownto bepreferredbybothdecisionmakersinmostcases.Thecommitmentbecomesinstitutionalizedwhenaconsensusexists amongallthepartiesexante.Standardcorporatepolicy,forinstance,placesauditingauthorityinthehandsofthefirm’s boardofdirectors,ratherthantheCEO.5 Governmentsmakeallowancesaswelltopreventpublicauditsforreasonsof
nationalsecurity.
Naturally,insomecasescommitmentisnotalwayspossible.Theresultsofthepaperinformthesecasesaswell:without commitment,discretionaryauditingwilloccurmakingallpartiesworseoffunderalargeenoughideologicalbias.Atthis pointthelossofwelfarerelativetothedisclosureregimemaywellbecomeapparenttotheparticipants,butitsimplyistoo latetoavoidit.
Inourviewthisisatleastpartofthereasonwhy“audits”inthepoliticalsphereareoftenviewedas“partisanwitch hunts”where“allactorsinvolvedinaccountabilityprocessesuseavarietyofstrategiestoarguetheircaseandapportion blame”(Boinetal.,2008).A“witchhunt”ofthistypecanbeusedtouncoverembarrassingfactsaboutone’spoliticalrival. Inthelanguageofthemodel,themorepreciseistheembarrassinginformation,theeasieritisfortheinvestigatingpartyto implementitsidealpolicychoice.
Indeed, the frequency of partisan investigations is an indication that institutional commitments to avoid audit-ing/investigatingaremoredifficultinpoliticalsystems.
“Partisaninvestigationshavehistoricallybeenapoxonbothhouses[intheU.S.Congress]–embarrassingthe inves-tigatorsasmuchastheinvestigatedandwoundingthemajorityparty.[...]Toooften,investigativehearingsturnout tobeflightsofvanityforacommittee’smemberstospeechifyandhumiliatewitnesses.”–Goldberg(2010)
Thedestructivenatureofsuchinvestigationssuggestsaparadox.Infirms(whereagencybiasisprevalent),commitmentto forgoauditingmaybepossiblethoughunnecessarysinceauditswillalwaysbechoseninequilibriumregardlessofwhether commitmentispossible.Inpolitical systems,auditsoftenassumetheformofapartisaninvestigation.Inthis casethe commitmenttoforgoauditingwouldbechoseniffeasibleandwouldinfactbepreferableforallpartiesifthebiasislarge enough.Unfortunately,commitmentsofthistypearenotusuallycodifiedinpoliticalsystemsandmaythusbeinfeasible.
Theremainderofthepaperisorganizedasfollows.Section2discussesrelatedliterature.Section3setsoutthemodel.In Section4wecharacterizeequilibriaunderbothideologicalbiasandagencybias.Section5examinestherobustnessofthe mainresults,includingtheextensiontomixedstrategies.Section6concludeswithabriefdiscussionoftheaccountability systemsfoundinfirms,polities,andinformalcollectiveactionscenarios.AllproofsarerelegatedtoanAppendixtothe paper.Aprefixof“A”inthenumberingofequationsandsoonindicatesthattherelevantitemcanbefoundinAppendix.
2. Relatedliterature
Weexaminetheequilibriumchoiceofdisclosure,auditing,ordirectverificationbytheuninformedagent.Withsome exceptions(discussedbelow)mostoftheliteratureexaminesoneofthesetransmissionmechanisms,butdonotavailall theoptionstothemodeledagents.
Thereisawellestablishedliteratureon(costly)stateverificationbeginningwithTownsend(1979)(seeBoltonand Dewatripont,2005forfurtherreferences).Bywayofcomparison,therelevantfeatureinourmodelisthatstateverification doesnotariseinequilibriumwhenauditinganddisclosureareavailable,evenwhenverificationcostsaresmall.
DisclosureisthemainfocusofthecheaptalkcommunicationliteraturebeginningwithCS.6Thepresentpapercontains
elementsofdynasticcheaptalkreminiscentofSpector(2000)andAnderlinietal.(2012)(AGL)whichexaminetheeffectsof biasamongmultipledecisionmakersandtheincentivestodisclosethecontentsofone’sobjectivesignals(viacheaptalk) toothersinthetemporalchain.Inthesepapers,cheaptalk(disclosure)wastheonlyoptionfortransmittinginformation; neitherauditingordirectverificationwereavailabletotheuninformedagents.
5See[13].
ConditionallyonDM2notcommittingtodisclosure,thepresentmodelisconnectedtothevastliteratureonsignaling startedbySpence(1973),sinceauditinginvolvestheverificationofpayoffrelevantdecisions.Amodelrelatedtooursin thesignalinggenrecomesfromCarrilloandMariotti(2000)who examineasingleagentproblemwithpresent-biased preferences.Giventhebias,theirmodelmaybere-interpretedasamultipleagentdecisionproblem–asinthepresent model.Theirfocusison“voluntaryignorance,”i.e.,when/whetheranagentchoosestostoplearning.Inasense,thepresent modelalsoconcernsvoluntaryignorance–inthiscasebythereceiverwhomightchoosetocommittodisclosureandhence notto“learn”fromthesender.DaughetyandReinganum(2010)focusonarelatedquestionfromasocialwelfareperspective. Theyexamineaplanner’schoiceofprotocolinapublicgoodsprovisionproblembetweenprivacyrightsofanindividualand thesocialbenefitofexposingfreeriders.Our“wordsversusactions”tradeoffsomewhatresemblestheir“privacyversus publicinformation”trade-offeventhoughthereisno(cheaptalk)communicationinthelatter.
Anumberofpapershavecomparedoutcomeswhendifferenttypesofobservationtechnologiesarevaried.Prat(2005)
comparesdifferentmodelsinwhichaprincipalcanobserveeithertheactiondirectlyorinsteadanoisysignal.Otherpapers haveexamineddifferenttypesofcommunicationprotocolsthatmaybechosenbythesender.Austen-SmithandBanks (2000)andKartik(2007)allowthesendertochooseamonganarrayofbothcostlessandcostlymessages,thelatterreferred toas“moneyburning.”Theirresultsdemonstratehowtheprecisionofcheaptalkincreaseswiththeadditionofthemoney burningoption.KaramychevandVisser(2011)goastepfurtheringivingafullcharacterizationoftheoptimalexante equilibriumforthesenderinthemodelwithbothcheaptalkandmoneyburning.Kartik(2009)incorporateslyingcosts intothecheaptalkmodeltherebyturningcheaptalkintocostlysignaling.Heshowsthatequilibriaexistexhibitingfull separationincertainregionsofthetypespace,somethingthatisnotpossibleinthestandardCSmodelwithacontinuum oftypes.
Ourpaperdiffersfromtheseinthatweexaminethesignalingvalueofpoliciesratherthanthatofpuremoneyburning. Inthissense,thepresentpaperismorerelatedtoDaughetyandReinganum(2008)whostudytheendogenouschoiceof protocolbyfirmsthatattempttorevealqualityoftheirproducts.Intheirmodel,afirmcandisclosequalitythroughdirect claims,oritcansignalqualitythroughitsproductchoices.
Themaindifferencebetweenthesepapersandoursisthatweplacethechoiceofcommunicationprotocolinthehandsof thereceiverratherthanthesenderoraplanner.Whileprotocoldecisionsbythesenderarequitenaturalinamarketsettings –firmsvisavisconsumers–studiedbyDaughetyandReinganum(2008)andAusten-SmithandBanks(2000)amongothers, wethinkitquitenaturalthatthereversewouldbelikelywithinfirmsandgovernmentswheredynasticconsiderationsplaya role.Inthesecases,theactorsfeartheirpoliciesmaybeundonebyfuturedecisionmakersiftheinformationwererevealed. Hencetheiractionswouldnotordinarilycometolightunlessanexplicitauditmakesitthecase.
3. Themodel
TherearetwoDecisionMakers–DM1andDM2.Thefirsthasdecisionauthorityattimet=1andthesecondattimet=2. TheactionschosenbythetwoDMsinthetwotimeperiodsaredenotedbya1 ∈Randa2 ∈Rrespectively.
3.1. Payoffs
Thesymbol ∈Rdenotesthevalueofastateofnaturethatisdrawnonceandforallfromastrictlypositivecontinuous densityfdefinedonthereallineR.Thestateisdrawnbeforeanythingelsetakesplace.
Thetwodecisionmakersaredifferentiatedbyabiasparameterb>0.Thisparameteristhesourceofthepreference misalignmentbetweenthetwoDMs.Hence,itisthekeydriverofallequilibriumdecisionsinthemodel.Weconsidertwo canonicalcases.
ThefirstwecallIdeologicalBias,withpreferencesofDM1andDM2,respectively,givenby
V1=−(a1−−b)2−(a2−−b)2, and V2=−(a1−)2−(a2−)2 (1)
Here,theidealpolicyofDM1ineachperiodt=1,2isat=+bwhereastheidealpolicyforDM2isat=.WerefertoDM1as
being“biased”inbothperiodssincehisidealpolicyis“distorted”upwardbyb.7
WetermthesecondcanonicalcaseAgencyBias,withpreferencesofDM1andDM2,respectively,givenby
V1=−(a1−−b)2−(a2−)2, and V2=−(a1−)2−(a2−−b)2 (2)
Underagencybias,thepreferencemisalignmentisdrivenbytherolethateachDMhasineachperiod:activepolicymaker orpassivestakeholder.EachactiveDMisbiasedfortheactionthatcorrespondstotheperiodinwhichheistheactivepolicy maker,andunbiasedwhenheisa“passivestakeholder.”Hence,DMtideallypreferspolicyat=+bineachperiodt=1,2,
whereasDM( /=t)ideallyprefersat=.Ourterminologyinthiscaseismotivatedbythefactthatagencyproblemsarise
fromthemisalignmentofpreferencesbetweensomeonewhoactuallycontrolsapayoff-relevantvariable(theagent,orthe
7 Ofcourse,the“bias”labelisrelative.Moreover,theactualdirectionofthepreferencemisalignment–DM1’sidealpointislargerthanDM2’s–is inessential.Wecouldallowforb<0.
activeDMineachperiodinourmodel)andapassivestakeholderwhoisaffectedbythechoicebuthasnodirectcontrol overit(theprincipal,or,inourmodel,DM2inperiod1andDM1inperiod2).
Ourterminologyisintendedtocaptureinherentincentiveconflictsinvariouscollectivedecisionsettings.Asastylized representation,ideologicalbiascanbefoundinpoliticalinstitutionsinwhichanoutgoingpoliticalpartyhassystematically differentpolicypreferencesthanitsnewlyelectedrival.Agencybiascanbefoundinfirmsinwhichamanager’spreferences aremisalignedwithhisorhersuccessororpredecessor,andDM2isselectedinternallyfromexistingmanagement.This newmanager,moreover,willhavepreferencesovertheuseofmanagerialperks(sayprivatejets),whileapastmanager whoholdsstockoptionsawardedduringhistenureasamanageronlyhaspreferencesformanagerialactionsthatinduce stock-appreciation.Theagencybiascasecanalsoapplytopoliticiansprovidedtheyareprimarilyoffice-motivatedrather thanideologicallydriven.Bothtypesbiascanbefoundininformalgroupsthatcoalescetosolvecollectionactionproblems.8
ThebiasesofthethetwoDMsinthetwoperiodsinthetwocanonicalcaseswehaveidentifiedarerepresented schemat-icallybelow.
(3) Notethatineithertheideologicalortheagencybiascase,asb→0theconflictbetweentheplayersvanishes.
3.2. Information,auditing,anddisclosure
Inthissubsection,weintroducetheformalauditingmodel.Thefocusisonhowthedegreeofconflict–asrepresented herebyb–distortstheincentivesofdecisionmakersateachdecisiondate.
Crucially,weassumethatneitherthestatenorthefirstperiodpolicyisautomaticallyobservedbyDM2.Specifically, thestateandthefirstperiodpolicya1areknownonlytoDM1,unlessDM2makesitapointtoverifythem.DM2therefore
assumespowerint=2knowingonlythatisrealizedfromacontinuousstrictlypositivedensityfdefinedonR.
Afterobservingandchoosinghispolicya1,theinformedagentDM1choosesamessagem∈Rthatcaninprinciplebe
usedtocommunicateor“disclose”somethingaboutthevalueofthestate.WerefertomessagemasDM1’sdisclosure statement.This,aswediscussedearlier,cantakeeitheroralorwrittenform.
Obviously,ifthedisclosurestatementfullyrevealedthestate,thenDM2wouldhavenoreasontoinvestigateor other-wiseexpendanyefforttoverifytheinformation.However,thebiascreatesamisalignmentinpreferencesoverthesecond periodpolicy.Hence,justasinthewellknowncheaptalkenvironments,themessagebyDM1willneverbefullyinformative. Knowingthisinadvance,theuninformedDM2hasachoicebeforeanypoliciesordisclosurestatementsareundertaken. ShecanchoosetorelyexclusivelyonDM1’smessageandtherebyforgoanyattempttoverifytheinformation.Alternatively, shecanholdopentheoptiontoseekadditionalinformationlateronafterthepoliciesanddisclosureoccurred.
Formally,welet∈{0,1}denotethe“commitment”choiceofDM2.Thechoice=1denotesthecommitmentbyDM2 toforgobothapolicyauditandstateverificationandhencetorelyonmalone,while=0denotes“keepingonesoptions open.”Choosing=0,DM2choosestoexercisediscretionaryauthorityatalaterdateoverwhatinformationshewillseek.
Iftheuninformedagentoptsfordiscretionaryauthority(=0),shesubsequentlyhasthreechoices,i.e.,threemethods ofobtaininginformationafterDM1’sdecisions.DM2can(i)stillchoosenottoaudit,andthereforerelyonlyonthemessage (wedenotethischoicebyNAfor“noaudit”),(ii)undertakeacostlessaudittoverifythepolicychoicea1ofDM1(wedenote
thischoicebyPA,for“policyaudit”),or(iii)undertakeacostlyaudittoverifythestatedirectly(wedenotethischoicebySV, for“stateverification”).Tosimplify,weassumethatbothSVandPAare“perfect”inthesensethatSVfullyrevealsthestate ,whilePAfullyrevealsthefirstperiodpolicychoicea1.Weletthechoiceacrossthesethreepossibilitiesbedenotedbyd
sothat
d∈{NA,PA,SV} (4)
Otherthingsequal,DM2wouldsurely(weaklyatleast)preferStateVerificationoveraPolicyAuditsincethestate,not theprioraction,isrelevanttoherpolicychoiceinperiod2.Ontheotherhand,theactofverifyingthestatedirectlymay bedifficultorcostlyinmanycommonsituations.Moreover,thefirstperiodpolicy,whilehavingnodirecteffectonthe
8Oneexamplesuggestedtousbyarefereeconcernsacommonpoolproblemwithanunknownresourcestock.Initialusersofthestock(e.g.,fisherman) observeinformationaboutthestock(thefishingthatdaywasgood)whichcanbecommunicatedormonitored(audited)bysubsequentresourceusers. Agencybiasariseswhenthe“catch”isapurelyprivategood,whereasideologicalbiasariseswhentheusershavedifferentpreferenceintensitiesovera “sharedcatch.”
secondperiodpayoff,maynonethelesshavesignalingvalueforthedecisionmakers.Inotherwords,sinceaffectsDM1’s preferencesoverhischoiceofa1,itisclearthataPolicyAuditcanrevealinformationabout.
Ofcourse,ifSVismuchmorecostlythanPA,thenitisnotaviableoption.TocapturetheideathatSVisonlymarginally morecostlythanSV,weassumethatPolicyAuditsarecostlesswhileStateVerificationcarriesalexicographiccost.9The
assumptionofzerocostforPAiswithoutlossofgeneralityasitpertainstoourmainresult.Specifically,themainresulthere refersthesurprisingoutcomethatDM2maycommittodisclosureandthusforegoPAandSV.AddingacosttoPAtherefore onlyreinforcesthisresult.Moreover,ifthePAcostissufficientlysmall,allourresultsgothrough.10
Thetimingisdepictedschematicallybelow.
3.3. Equilibrium
Weleta1=˛1(,)denotethechoiceofpolicybyDM1givenhisobservationofandDM2’schoiceof.Similarly,we
letm=(,)denoteDM1’schoiceofmessagem.Wealsodenotebyz(,d)theactualobservedoutcomecorrespondingto thetransmissionchoicesanddbyDM2.Accordingtothemodel,z(1,d)=mforalld(i.e.,DM2choosestocommittoview onlymessages),z(0,d)=mwhend=NA,z(0,d)=whend=SV,andz(0,d)=a1whend=PA.Finally,leta2=˛2(z(,d))denote
DM2’schoiceofpolicygivenherobservationz(,d).
WeevaluatekeypropertiesofthePerfectBayesianEquilibria(PBE)ofthegame.FornowwerestrictattentiontoPBEin purestrategies,definedformallybelow.Asidefromthesimplificationthisaffords,weshowinSection5thatmixedstrategy PBEarenon-genericinthebiasparameterb.Moreoverinthose(non-generic)caseswheremixedPBEmayexist,onecan constructapurestrategyPBEthatispayoffequivalentforDM2.
Inthedefinitionbelow,wewillrefertoaPBEissimplyan“equilibrium.”
Definition1. Equilibrium:Anequilibriumisa5-tuple(˛1,,,d,˛2)suchthat
(1)DM1choosesthepair(˛1,)optimallygivenherobservationofandandDM2’s(correctlyanticipated)choiceofd
and˛2.
(2)DM2choosesthetriple(,d,˛2)optimally.Inparticular,anddarechosengivenherbeliefsaboutandhercorrect
anticipationofDM1’schoiceof˛1and.DM2’schoiceof˛2issimilarlyoptimal,reflectingherupdatedbeliefsafter
observingz(,d).
(3)DM2’supdatedbeliefssatisfyBayes’Rulewhereverpossible.
Wefirstestablishabaselinepartialcharacterizationofequilibriathatwillbehelpfulforsubsequentresults.
Proposition1. Fullrevelationwithoutcommitment:Consideranyequilibriumineithertheideologicalortheagencybiasmodel. SupposethatintheequilibriumDM2chooses=0.Thatis,DM2doesnotcommittoobservingonlymessagemandinsteadretains theoptiontoconductapolicyauditorverifythestateatalaterstage.Then
(i)DM1’schoiceofa1=˛1(0,)isfullyrevealingofthestate.
(ii)DM1’smessagestrategy(0,·)inthecontinuationgamefollowing=0coincideswithsomePBEstrategyintheCScheap talkgame.
(iii)DM2choosesapolicyauditsothatd=PAandz(0,PA)=˛1(0,).
(iv)DM2choosesheroptimalsecondperiodactiona2=˛2(z(0,PA))=˛2(˛1(0,))=.
OnesignificantimplicationofProposition1isthatinaworldwherethecommitmenttoforgopolicyauditingandstate verificationisnotpossible,theuninformedagentwouldalwayschoosetoundertakeapolicyaudit.Shewouldneverrelyon messagesalone,andshewouldneverchoosetoverifythestatedirectly.
Intheinterestofbrevity,weomitafullformalproofforProposition1.Theargumentisstandardandwhatfollowsisa sketchofthestepsinvolved.
9 Thatis,PAiscostlesstoimplementbyDM2,andDM2choosesSVifandonlyifthepayoffafterobservingthestateisstrictlylargerthanthepayoffafter observingDM1’saction.
Assumethatinsomeequilibrium,=0.WhenDM2choosesditisnotpossiblethatshewillsetd=NAandonlyobserve m.Inthiscase,giventhata1issunk,themodelwouldboildowntoaversionoftheCSworld,andthemessagewouldnotbe
fullyrevealingofthestate.HenceDM2coulddeviatetosettingd=SV,observe,andhenceattainahigherpayoff.
CoulditthenbethatDM2setsd=SVinequilibrium?InthiscaseDM1wouldanticipatethathischoiceofa1playsno
(informational)roleinDM2’schoiceofa2.HenceDM1wouldsimplychooseanactionthatmaximizeshis=1payoff,and
hencehischoiceofa1wouldbefullyrevealingofthestate.ButsincebothSVandPAwouldinducefullyrevealingactionsby
DM1andarethusequallyinformative,thepolicyauditPAispreferabletoDM2asthecheaperoption.Hence,DM2would thendeviatetochoosingPA.
ThisinturnmeansthatonlypossibilityisthatDM2choosesPAwhengiventhechance.Coulditbethatthisisthecase andDM1’schoiceofa1isnotfullyrevealingof?Ifthiswerethecase,giventhatlexicographiccostofchoosingSV,DM2
wouldthengainbydeviatingtochoosingSV.Thiswouldgivehermoreinformationandhenceallowhertoimproveher payoff.Hence,weconcludethatinanyequilibriumif=0ischosenthend=PAisalsochosenbyDM2,andfurthermorethat thechoiceofa1onDM1’spartmustbefullyrevealingofthestate.
FromProposition1,theonlycandidatesforequilibriumareeitherforDM2toeitherrelyonthe“words”(thecaseof=1) orthe“actions”(thecaseof=0andd=PA)ofDM1.NoticethatwhileSVwillneverbechoseninequilibrium,itsavailability iscrucialtotheargument.Withoutit,d=NAcouldbechosenbyDM2and,consequently,thepolicyofDM1neednotbefully revealing.
4. Whendoactionsspeaklouderthanwords?
4.1. Ideologicalbias
Webeginwiththecaseofideologicalbias.InthiscaseDM1andDM2differintheirobjectivesinthesamewayacrossthe twoperiods.ForanygivenDM1’sidealpolicyislargerthanthatofDM2.Asweremarkedbefore,thistypeofmisalignment onpreferencesisastylizedrepresentationofpoliticalcompetitionbetweentwopartiesthatholdpowerinsequencebut haveapre-setdifferenceofopinionregardingthedesirablevaluesofagivenpolicyvariable.
FromProposition1weknowthatinthecontinuationofthegamefollowing=0(nocommitment),DM2choosesd=PA andDM1’schoiceofa1mustbefullyrevealingofthestate.Giventhatincheaptalkmodelswithacontinuumofstates(à
laCS)fullyinformativeequilibriaaregenerallyruledout,thepicturethatemergesfromProposition1seemstosaythatin equilibriumweshouldnotobserveDM2actuallycommittoonlyobservingthecheaptalkmessagem.
Yet,thisintuitionturnsouttobefalseinarobustsetofenvironments.ThemainresulttellsusthatwithIdeologicalBias andfor“largeenough”valuesofb,everyequilibriumwillhavethepropertythatDM2commitstoobservethemessages. ThegistoftheargumentreliesonfindingupperandlowerboundsforDM2’spayofffollowingachoiceof=0and=1 respectively.Thisisthereasonwefirststateapreliminarycharacterizationofequilibria,whichsharpenstheconclusionof
Proposition1inthecaseofIdeologicalBias.
Proposition2. Linearpareto-dominantequilibrium:ConsidertheIdeologicalBiascase.IfthereisanyequilibriuminwhichDM2 chooses=0,thenthereisanequilibriumasfollows.
(i)DM2chooses=0.
(ii)DM1’schoiceofpolicyisgivenby˛1(0,)=+2b.
(iii) ThepayoffsassociatedwiththisequilibriumPareto-dominatethoseofallotherequilibriainwhichDM2chooses=0. Forlackofabetterterm,wewillrefertotheequilibriumdescribedinthePropositionasthelinearequilibriumunder IdeologicalBias.Wearenowreadytostateourfirstmainresult.
Proposition3. Sometimeswordsdospeaklouderthanactions:ConsidertheIdeologicalBiascase.Thenthereexistsa ¯b>0such that
(i)Ifb> ¯b,theninanyequilibriumDM2selects=1.Inotherwords,inallequilibriaDM2commitstoobservingmonlyand forgoestheoptiontoconductapolicyauditortoverifythestateatalaterstage.
(ii)Ifb≤ ¯b,thenthereexistsanequilibriuminwhichDM2selects=0,subsequentlychoosestoauditDM1’spolicy(selectsd=PA) andDM1playsaccordingtothelinearequilibriumofProposition2,thussettinga1=˛1(0,)=+2b.
Obviously,thestrongerandmoresurprisingclaiminProposition3ispartiwhichappliestoeveryequilibriumofthe gamewhenb> ¯b.Thus,withalargeenoughideologicalbiasDM2commitstoobserveonlym.Wordsspeaklouderthan actions.
Weemphasizethatthecommitmentoptiontoforegoadiscretionaryauditappearsinmanyenvironments,including nationalsecurityissuesandstandardcorporatepractices.ThePropositionprovidesonerationaleforwhytheoptionwillbe exercised.WelatershowthattheresultholdsupevenifthecommitmentbyDM2requiredtheconsentofDM1.Forbias largeenough,bothpartieswouldprefertoavoidtheaudit(seeSection5).
ThefullProposition3isinAppendix.Tounderstandtheresult,however,wefinditusefultofirstdeveloptheintuition forparti.Later,wecommentonpartii.
Sinceweareinthecaseofideologicalbias,foranygivenlevelof,DM1’sidealactionsare+bbothinperiod=1and =2.TheseconddecisionmakerDM2favorsactionsequaltoinbothperiods.
Asthe“receiver”ofinformation,DM2choosestoset=1ifbislargeenough.Insodoing,DM2commitstoobserve messagemonly.NotethatDM2losesvaluableinformationsince,justasinCS,misnotfullyinformativeof.Infactthe degreeofinformativenessofmdecreasesasthesizeofbincreases.
AftertheDM2chooses=1,DM1effectivelychoosesa1 “insecret.”HenceDM1willsimplyseta1=+b.Therefore,
regardlessofthefirstperiodpayoffofDM2is−b2(see(1)).DM2thenchoosesa
2afterobservingm,andhence(using(1)
again)hersecondperiodexpectedpayoffcontingentonmis−Var(|m).11
IfDM2weretoset=0instead,weknowfromProposition1thatitwillsubsequentlychoosetosetd=PA,andhence observea1directly.Thekeytoseeingthat,forlargeenoughb,thiswillbeworsethansetting=1,istonotethatafterDM2
sets=0,DM1knowsthata1willbeauditedbyDM2inthesecondperiod(againweobservethefactthatSVisavailable
anddominatesNAiscriticaltothisargument,eventhoughSVisneverchoseninequilibrium).ByProposition1,DM2will havefullinformationaboutonceitobservesa1.ThereforeDM2setsa2=,andthisgivesDM2asecondperiodpayoffof0.
KnowingthatDM2willusetheinformationyieldedbythePolicyAudittoseta2=willinduceDM1to“over-compensate”
duetothemarginaleffectofitsfirstperiodactiononDM2’saction.DM1thereforesetsavalueofa1thatisabove+b.In
fact,weknowfromProposition2thatinthebestcaseforDM2(and,forthatmatter,forDM1aswell),a1willbesettoequal
+2b.Hencethefirst-periodpayofftoDM2isnowworsethantheonewecalculatedfollowing=1sinceitis−4b2.12Since,
aswenotedabove,thesecondperiodpayofftoDM2iszero,thismeansthatitsoverallexpectedpayoffaftersetting=0is atbest−4b2.
Tosumup,DM2’sexpectedpayoffaftersetting=1isboundedbelowby−b2−Var(),whileaftersetting=0itis
boundedaboveby−4b2.Sincethedistributionofisgiven,itisthenclearthatwhenbissufficientlylargeDM2mustprefer
toset=1andthusforgoanyPolicyAuditorStateVerificationandrelyonlyonthecheaptalkmessagemsentbyofDM1. Wordsdospeaklouderthanactionsinthiscase.Infact,itisnothardtoextendtheargumentusedtoproveProposition3to showthatifbissufficientlylarge,thenDM2’scommitmenttoobserveonlymisbeneficialtobothplayers.
ThestatementinPart(ii)ofProposition3isnotassharpasonewouldideallylikebecauseoftheunderlyingmultiplicity ofcontinuationequilibriafollowingboth=0and=1inthecasewherebissmall.
TheequilibriumidentifiedinPart(ii)ofProposition3issupported(seeAppendixforthedetailsoftheargument)by choosingababblingequilibriumcontinuationfollowinga choiceof=1andthelinear(Pareto-dominant)equilibrium identifiedinProposition2followingachoiceof=0.
InthemodelweanalyzeitisDM2whochooseswhetherthegamecontinueswithanoptiontoperformPolicyAudit orStateVerificationortoshutdowntheseoptionsandcommittoobservingmonly.Itisthereforelegitimatetoaskwhat happensif,inthespiritofforwardinductionarguments,13werestrictattentionto“continuationequilibria”thatgivethe
bestpossiblepayofftoDM2bothafterachoiceof=0andafterachoiceof=1(thelatterisnotababblingequilibrium).
Definition2. Forwardinductionproofequilibrium:Consideranequilibrium ofthegeneralgame.We defineaforward inductionproofequilibrium(henceforthaFIPE)asaPBEsuchthatthereisnootherPBEwhichyieldsalargercontinuation payofftoDM2followingeitherofitscommitmentactions,either=0or=1.
Inotherwords,aPBEisaFIPEifitmaximizes,amongallPBE’s,DM2’scontinuationpayofffollowinghercommitment decision.Inthespiritofforwardinduction,DM2indicatesherintentionsaboutwhichactionshe’lltakefromherinitial commitmentdecision.Off-pathbeliefsofDM1acceptstheseintentionsandactsaccordingly.
Beforestatingtheresult,werequireonemoreassumption.
Assumption1. Constantdensity:Thestrictlypositivecontinuousdensityffromwhichisdrawnisconstantonsome non-degenerateinterval[, ¯].
Proposition4. ConsidertheIdeologicalBiascaseandletAssumption1hold.Thenthereexistsab>0suchthatforanyb≤b themodelhasauniqueFIPEinwhichDM2sets=0,andsubsequentlychoosesd=PA.
Clearly,b< ¯bwhere ¯bistheboundinProposition3.So,withtherefinementandasmallenoughideologicalbias,apolicy auditmustoccur.Combiningthisresultwithpart(i)ofthepreviousproposition,weobtainasharpcharacterizationofthe chosenvehicleforinformationtransmissionwhenideologicalbiasiseithersufficientlylargeorsufficientlysmall.
11 TheactualvalueofVar(|m)dependsontheentiremessagefunction(·|0)chosenbyDM1inequilibrium. 12 SinceweknowfromProposition1thata
1isfullyrevealingofthestate,wecanwritetheincentive-compatibilityconstraintforDM1asbalancingthe marginal“tangible”payofffroma1(asitentersdirectlyDM1’sfirstperiodpayoff)anditsmarginaleffectonthebeliefsofDM2aboutandhenceona2. Thisgivesrisetoasimpledifferentialequation(see(.5)inAppendix)whichunderpinsthelinearequilibriumofProposition2.
13 Forreasonsofspaceandeaseofreading,westayclearofdetailsabouthowexistingforwardinductionrefinementsspecificallyapplytoourmodel. Instead,werefertheinterestedreadertothecontributionsbyvanDamme(1989),andmorerecentlybyGovindanandWilson(2009),andMan(2012).
4.2. Agencybias
Ourmodelbehavesquitedifferentlywhenthemis-alignmentinpreferencesbetweenDM1andDM2takestheformof AgencyBias.Recall(see(3))thatinthiscaseDM1favorsahigherlevelofa1thanDM2does,andsimilarly,DM2favorsa
higherlevelofa2thanDM1does.Themanagerwhoisactiveinanyperiod,foranygiven(theexternalmarketfactors
affectingthefirm),favorsahigherlevelofmanagerialperksthanintheperiodinwhichsheisnottheactivemanagerbut holds,say,stockinthefirm.
JustasinthecaseofIdeologicalBias,fromProposition1weknowthatonlytwoalternativesareviableinequilibrium. EitherDM2choosestocommittoobservingonlymandthusforgoesanypossibilitytoauditDM1’spolicyortoverifythestate (DM2sets=1),orshedoesnotcommitinsuchaway(DM2sets=0)andsubsequentlychoosestoobservea1(d=PA).
Recallalsothat,justasinthecaseofIdeologicalBias,Proposition1furthercharacterizesthissecondpossibilitytellingus thatinthiscaseDM1’schoiceofa1mustbefullyrevealingofthestate.
WefirststateourmainresultforthecaseofAgencyBiasandthenelaborateonitsmeaningandtheintuitionbehindit.
Proposition5. Underagencybiasactionsspeaklouderthanwords:ConsiderthecaseofAgencyBias.Then,foranylevelofb, thereisauniqueForwardInduction-Proofequilibrium(FIPE)inwhich
(i)DM2chooses=0therebynotcommittingtoobservingmaloneandretainstheoptiontocarryoutaPolicyAuditorState Verification.
(ii)DM2choosesapolicyauditsothatd=PAandz(0,PA))=˛1(0,).
(iii) DM2enjoyshergloballyoptimalpayoffof0.
NotethatcombiningProposition5withProposition1weknowthatintheequilibriumsingledoutbyProposition5,DM2 proceedstosetd=PAandsotoauditDM1’spolicyandobservea1directly,thusgainingfullknowledgeoftheactualvalue
of.
JustasinthecaseofProposition3,theremaybeamultiplicityofPBE.However,FIPErulesoutanycontinuationother thantheoneinwhich(a)thefullyrevealing(linear)equilibriumisplayedfollowingthechoiceof=0,and(b)thebestCS equilibrium(fromDM2’spointofview)isplayedfollowingthechoiceof=1.Facedwiththesetwocontinuations,DM2 willchoose=0intheagencybiasmodel.
Theintuitionfortheresultcanbeunderstoodbyjuxtaposingtheagencybiasmodelwiththeideologicalbiasmodel.In bothmodels,theactionofthefirstdecisionmaker,DM1,playstworoles.Firstly,ithas“tangible”valueforbothDM1and DM2sinceitentersdirectlytheirpayoffs.Secondly,ithasasignalingrolesinceitpotentiallyrevealstheactualvalueofto DM2–infact,byProposition1,itactuallydoesrevealitinanyequilibriuminwhich=0.Inbothmodels,themarginaleffect (viasignaling)ofDM1’sactiononDM2’sactionwillbeweightedbyDM1togetherwiththetangiblevalueofheractionasit entersherfirstperiodpayoff.
Unliketheideologicalbiasmodel,underagencybiasDM1wouldliketodistortDM2’sactiondownwardratherthan upward.Inordertodothisviasignaling,hisownactionshouldbelessdistortedthanwouldbeoptimalfromapurely tangiblepayoffpointofview.Thatistosay,thesignalingvalueofDM1’sactionworksinoppositiontoitstangiblevalue. Thisisquitedifferentthantheideologicalbiascasewheretangiblevalueandsignalingvaluearereinforcing–bothmotivate DM1todistorthisactionupward.
UnderagencybiasthetwoopposingforceseffectivelycanceloutmakingDM1’schoiceequaltotheonethatisthe overallfavoriteofDM2,namelya1=.14HenceDM2endsupenjoyingheroveralloptimalpayoffunderaPolicyAuditthatis
anticipatedbyDM1.Henceshechoosesnottocommittoobservingmonlywhengiventhechance.Actionsdoindeedspeak louderthanwordsintheAgencyBiascase.
5. Robustness
Anumberofextensionsor“robustnesschecks”areworthdiscussing.Weintroducewhatwebelievearethemostcritical onesandanalyzeeachinturn.
Mixedstrategies.Theanalysisthusfarfocussedexclusivelyonpurestrategies.Wegiveabriefargumentdemonstrating themainresultsextendtothemixedstrategycase,althoughwedonotgiveaprecisecharacterizationofallmixedequilibria ofthemodel.
ConsiderfirstProposition1,theprecursortosubsequentresults.SupposeweareatthestageinwhichDM2didnotalready committodisclosureandmustnowchoosebetweenPA(auditing),NA(messages),andSV(stateverification)followingDM1’s choices.
IsthereanequilibriuminwhichDM2mixesatthisstage?NoticeattheoutsetthatDM2mustassignzeroprobabilityto NA.IfDM2assignspositiveprobabilitytoNA,thenDM1’smessageisnotfullyinformative(asshowninCS).Inthatcase, DM2strictlyprefersSVtoNAsincetheverificationcostissmallerthanitsbenefits.NoticealsothatDM2willnotrandomize
14ThedifferentialequationembodyingDM1’sIncentiveCompatibilityconstraint(see(.17)inAppendix)nowyieldsa
betweenPAandSV.IfDM1’sactionisfullyrevealing,thenDM2strictlyprefersPA.Iftheactionisnotfullyrevealingthen DM2strictlyprefersSV.Hence,inequilibriumDM2choosesPA.
WillDM2actuallybewillingtorandomizeatthecommitmentstage?Infact,thiscanhappenonlyifDM2isindifferent betweenPAandNA.Intheideologicalbiascasewithblarge,babblingisstrictlybetterforhimthanthefullyrevealing continuation.15Similarly,witheitheragencybias,orideologicalbiaswithbsmall,thefullyrevealingcontinuationisstrictly
betterthananyother.
Inshort,indifferencebyDM2isnon-generic.Moreover,iftheredoesexistanequilibriuminwhichDM2mixes,thereis apurestrategyequilibriumthatispayoffequivalent.
Auditingcosts.Themodelassumesthatauditingcostsarezero.Considerwhathappenswhenweallowforpositive auditingcostsinthemodel.Theresultsholdupifauditingcostsareintroduced,providedtheyaresmallenough.Thekey observationisthat,aslongasstateverificationismarginallycostlierthanthepolicyaudit,thelatterwillalwaysinduce fullyrevealingactionsbyDM1.Inthatcase,thepolicyauditwillalwaysbethebetteroption.Consequently,Proposition1, thegatewaytothesubsequentresults,continuestohold.Moreover,ifthePAcostissmallenough,thenitwillstillbethe preferredoptionoverdisclosureinthosecaseswherePAwaschoseninthemodelwithzeroauditingcosts.16
Noticethatifmixedstrategiesareintroducedinthemodelwithpositiveauditingcosts,theywillbenongenericforthe samereasonsoutlinedabove.Notealsothatif=1ischosenunderzeroPAcosts,thenitwillbechosenwhensuchcosts arepositive.Themoresubtlecaseiswhen=0andd=PA.SincethefullyrevealingcontinuationunderPAisstrictlybetter thananyotherwhenauditingcostsarezero,itwillbesowhencostsarelowenoughtopreservethestrictinequality.17
Discounting.Inadynamicmodel,itisnaturaltoaskwhathappensiftheplayersdiscountthefuture,sothatinourcase thesecondperiodpayoffsothatitismultipliedbyafactorı∈(0,1).Thegistofourresultssurvivesintactthediscounting ofsecondperiodpayoffsbyDM1andDM2.
Propositions2and3continuetoholdwiththeonlyamendmentthatthelinearequilibriumisnow˛1(0,)=+(1+ı)b.
Thethresholds ¯b andb< ¯b needtoberecalculatedforthediscountingcase,buttheirexistenceremainsexactlyasstatedin
Propositions3and4.Proposition5partialsocontinuestohold.
InshorttheoverallpictureframedbyPropositions3–5continuestoholdwhendiscountingisallowed.Wordsspeak louderthanactionsinthecaseofIdeologicalBiasandblarge,whileactionsspeaklouderthanwordswhenbissmalland weareintheIdeologicalBiascase,orforanyvalueofbwhenweareinthecaseofAgencyBias.
Theabilitytocommit.Weremarkedearlierthatcommitmentstoforegoauditsarecommonpracticeinfirms.Toa morelimitedextent,theyalsoexistinpolities–particularlyinareasofnationalsecurity.Onecouldtakeissuewiththefact that,unlikeourmodelwhereDM2makesthecommitment,thesecommitmentsareinstitutionalinnature.Theyareoften agreeduponeitherbynon-partisancommittees(e.g.,thefirm’sBoardofDirectors),orunanimousagreementbytheparties themselves.Ourresultscanbeextendedtoaccommodatethispossibility.
ConsideranextrastepinthemodelwherebyaproposedcommitmenttoforegoauditingbyDM2requirestheapproval ofDM1–aParetocriterionofsortsthatdetermineswhetherthecommitmenttousedisclosureistaken.Nowconsider twoinstitutions(formally,twodistinctgames).Inonegame,theonewe’veanalyzedsofar,thereexistsadecisionnodein whichDM2cancommittousedisclosure.Intheothergame,nosuchcommitmentoptionisavailable.Thatis,withoutthe commitmentoption,DM2mustsimultaneouslychoosebetweenallthreeoptions-disclosure,auditing,directverification afterDM1’saction.
Intheideologybiasmodelwiththecommitmentoption,whenbiasbislarge,Proposition3showsthatDM2prefers tocommittodisclosure.ButthisisalsotrueforDM1.Inotherwords,forblargebothdecisionmakersprefertomakethe commitment.Toseewhy,observethatunderauditing,DM1’stotalpayoffis−2b2.Underdisclosure,theworstcanhappento
DM1isbabblingandDM1’slowerboundinthiscaseis−Var()−b2.Thusforblarge,disclosure–thecommitmenttoavoid
auditing–Paretodominatestheoptiontoaudit.Inthissense,thetwoagentspreferaninstitutioninwhichacommitment optionexiststoavoiddiscretionaryaudits.
Bycontrast,whenbissmall,thenbothpartiespreferauditing.Inthiscasethepresenceorabsenceofthecommitment optioninthemodeldoesnotaffecttheoutcome.Thepartiesarethereforeindifferentaboutwhichofthetwogames,i.e., whichinstitutionalenvironment,theyarein.
Nowconsidertheagencybiasmodelwiththecommitmentoption.Here,whenthebiasbissmall,thenbothpartieswould preferauditing.AgainthereisaclearParetorankingbutthepresenceorabsenceofthecommitmentoptioninthemodel doesnotaffecttheoutcome.Thepartiesareonceagainindifferentaboutwhichofthetwogames,i.e.,whichinstitutional environment,theyarein.
Forthesakeofcompleteness,weobservethatwhenbislargeintheagencybiasmodel,DM2andDM1haveopposing preferencesonthecommitmentdecision.ByProposition4,thedecisioninthehandsofDM2resultsinauditing.18
15 WeemphasizethatDM1’schoicedependsontheoutcomeofDM2’smixedstrategy,notonthemixedstrategyitself.Forthisreason,DM1doesnotmix, andsoneitherdoesDM2exceptonanongenericsetofb.
16 Roughly,wecanboundthepayoffofthemostinformativecheaptalkequilibriumoftheCScheaptalkgame.SincetheactionbyDM1inthePA continuationisfullyrevealing,itwillbestrictlypreferrediftheauditingcostisverysmall.
17 TheremayofcoursebeanauditingcosttocreateanindifferencebetweenPAandNA,butthiscasewouldbenon-generic.
Hence,exceptforthislastcase,bothplayerswouldprefer,atleastweakly,tobeinaninstitution(agame)inwhichthe commitmentoption–theoptiontoforegodiscretionaryauditing–isavailable.
Quadraticlosspayoffs.Throughout,wehaveworkedwithpreferencesrepresentedbytime-separablequadratic-loss functions.SinceCS,quadraticpreferenceshavebeenthecanonicalbenchmarkcasethroughouttheliteratureon cheap-talk.Acrossthisfield,quadraticpreferencesalsohavetheprivilegedpositionofguaranteeingtractability,yieldingexplicit solutionsinmanycases.Theyplayessentiallythesameroleinourmodel.
Itislegitimatetoaskhowcrucialtheirroleisinthequalitativeflavoroftheresultsweobtainhere.Wedonotdemonstrate ageneralresultinthepaper,however,thenatureoftheresultsindicatethatthesepreferencesarenot“knife-edged.”
AsimplewaytoseethisistoobservethatDM2’stransmissionchoicesarediscreteandgenericallyherbestresponsesin equilibriumarestrict.Thismeansthattheargumentsshouldgothroughunchangedinawelldefinedcontinuousparametric neighborhoodofthequadraticpreferences.Totakeoneexample,supposeWi=Vi+(1−)UiwhereViisthequadraticpayoff
specifiedbeforeandUiisasmoothfunctionofactions,stateandbiasandstrictlyconcaveintheaction.Fortheresultto
extend,onewouldshowthattheresultsremainintactforWiifiscloseenoughtoone.19Westronglyconjecturethisis
thecase,butdonotproveitformally.
6. Auditsandpartisaninvestigations
Thispaperhasemphasizedtheimportanceofendogenouschoiceoftransmissionprotocolindecentralizeddecisions problems.Therearemanysuchproblemsinwhichtheinterestsofrelevantdecisionmakersdonotcoincide.Wefocuson twocleavages–ideologicalandagency–thatdifferentiateauthorityfiguresatdifferentdecisiondates.
Theresultssuggestthatthecommitmenttoasystemofdisclosureismorevaluablewhenthecleavagebetweendecision makersisideological.Wearguedthat,broadlyspeaking,theIdeologicalBiascasefitsbetterthepoliticaleconomyscenarioin whichtwopartiessuccessivelyholdpower,whiletheagencycaseisarguablybettersuitedtorepresentprivateorganizations inwhichtwodecisionmakersarechoseninternallytoheadtheoperationsinsuccession.20
This,inourview,talliessignificantlywiththefactthatAuditingdoesinfactprevailinthecaseoffirms.Audits(internal andexternal)arealmostalwaysthoughtofas“goodmanagementpractices”inthecaseofthefirms,21whereasauditsinthe
politicalsphereareoftenviewedas“partisanwitchhunts.”Whenanewpoliticalpartyoccupiespowerithaswidepowers torenegeonpreviouspromises,ifnecessarybychangingthelaw.Onenotableexceptionisintheareaofnationalsecurity. Institutionalcommitmentstoavoidpublicauditsofsensitivesecurityexistandareusuallyagreeduponbyallparties.
Itisworthemphasizingthatdecisionproblemsofthisnaturealsoariseinmoreamorphoussettings.22Whetherthe
institutionisformalorinformal,wepointoutthatiflegal/institutionalcommitmentsarefeasible,thenbothdecisionmakers atleastweaklyprefertheminallcases,agencyorideologicalbias,largeorsmallb,exceptunderagencybiaswhenbislarge. Finally,theresultsindicatethatwhensuchcommitmentisnotpossibletheoutcomewillinfactbeanAuditoftheactions ofthepreviouspartybythenewholderofpower.Atthispointthelossofwelfarerelativetothedisclosureregimemaywell becomeapparenttotheparticipants,butitsimplyistoolatetoavoidit.Afutureexplorationintowhen,how,andwhysuch commitmentsarepossibleinsomeenvironmentsandnotinotherswouldbewellworththeeffort.
Appendix.
ProofofofProposition2. Consider theIdeologicalBiascase,andassumethatthereisanequilibriumwith=0.By
Proposition1thenthereisanequilibriumwith=0,d=PAand˛1(0,)fullyrevealingof.Letthisequilibriumbedenoted
by(˛∗1,∗,∗,d∗,˛∗2).Foreveryvalueof,DM1’spolicychoicea1=˛∗1(0,)mustsolve
max
a1
−(a1−−b)2−[˛∗2(a1)−−b]2
Assuming˛∗2isdifferentiable,23wecanwritethefirstorderconditionas
˛∗1(0,)−−b+[˛∗2(˛∗1(0,))−−b]˛∗2(˛∗1(0,))=0
Since˛∗1(0,)isfullyrevealingandDM2’soptimala2isequaltoforanygiven,wemusthavethat˛∗2[˛∗1(0,)]=
˛∗1 −1[˛∗1(0,)]=.FromtheInverseFunctionTheorem,wethenknowthat˛∗2[˛∗1(0,)]=1/˛∗1(0,).
19Theexactcutoffsinbwouldobviouslybedifferent.
20Theserepresentationsare,ofcourse,approximate.Forinstance,office-motivatedpoliticians–asopposedtotheideology-drivenoneswehaveinmind here–mayfitbetterthecaseofAgencyBias.
21SeeArter(2000). 22Seefootnote8.
23Forthisstepoftheargumentofcourseitissufficienttoverifyex-postthatfunctionwefindisindeeddifferentiable.Intheproofofpartiii)belowthis isnotaviableoption.However,sinceweknowfromProposition1thatwearedealingwithfullyrevealingequilibriaitiseasytoseethatDM1’sdecision mustbecontinuousandstrictlymonotoneinandhencedifferentiablealmosteverywhere.Thisissufficientforourpurposesbelow,thoughthedetails areomittedforthesakeofbrevity.
Hence,thefirstorderconditionimpliesthatthefollowingdifferentialequationmustbesatisfied
[˛∗1(0,)−−b]˛∗1(0,)−b=0 (.5)
Noticethat˛∗1(0,)=+2bisonesolutiontothisdifferentialequation(and,pointbypoint,satisfiestherequiredsecond ordercondition).
ThissufficestoprovepartiiofProposition2.Forfuturereference,atthispointwenoticethat˛∗1(0,)=+2banda2=
foreveryimplyanequilibriumpayoffforDM2of−4b2.
ToshowpartsiandiiiofProposition2,usingpartiofProposition1,itissufficienttoshowthatthepayoffsassociatedwith thelinearequilibriuminwhich=0and˛∗1(0,)=+2bPareto-dominatethoseofanyotherfullyrevealingequilibrium inwhichDM2sets=0.
Consideragainthedifferentialequationin(.5),whichweknowanyfullyrevealingequilibriumtobeconsideredhere mustsatisfy(almosteverywhere).
Define
g
=˛1(0,)−−b (.6)andnotice
g()=˛∗1(0,)−1 (.7)
Hence,wecanrewrite(.5)as
g
1+g=b (.8)
Theng*()=bisonesolutionto(.8),givingrisetothelinearequilibriumstrategy˛∗
1(0,)=+2bthatweidentifiedabove.
In general, however, there are infinitely many solutions to (.8), corresponding to infinitely many fully revealing equilibria.24
Oncewehaveagthatsolves(.8),foranygiventhepayoffstothedecisionmakersinthecorrespondingequilibrium, canberespectivelywrittenas
V1=−g()2−b2 and V2=−[b+g()]2
Moreover,observethat,wheneverg()>0,bothpayoffsaredecreasinging().
Therestoftheproofconsistsofshowingthatifgisasolutiontothedifferentialequationin(.8)andg /= g*,theng()≥b
forevery.Thiswillsufficetoshowthatinanyotherequilibriumtobeconsideredthepayoffstobothdecisionmakersare lowerthanthoseonthelinearequilibrium,asrequired.
Consideragainthedifferentialequationin(.8).Beginbynotingthatdirectlyfromthedifferentialequationitselfweknow thatitisimpossiblethatg()=0forany.Hence,sincegiscontinuousanddifferentiablealmosteverywhere,ifg(ˆ)is positive(negative)forsome ˆtheng()mustbepositive(negative)forall ∈R.
Now,bywayofcontradiction,considerasolution ˜g to(.8)suchthatforsome ˆ wehave ˜g(ˆ)<b.Weneedtodistinguish betweentwocases–first ˜g(ˆ)>0,andthen ˜g(ˆ)<0.
Considerthecaseof ˜g(ˆ)>0first.Sincebyourcontradictionhypothesis ˜g(ˆ)<b,directlyfrom(.8)wegetthat ˜g()< ˜g()<bforallpairs{,}satisfying<and< ˆ.
Restrictingattentiontoanappropriatesubsequenceifnecessary,wethenhavethat lim
→−∞˜g
()=0.Since ˜g()<bforall
< ˆ,thisimpliesthatforsomesufficientlysmall ¯ itmustbethat
˜g( ¯)[1+ ˜g( ¯)]<b (.9)
whichdirectlyimpliesthat ˜gcannotbeasolutionto(.8).
Wenowturntothesecondcase–so,assume ˜g(ˆ)<0.Similarlytowhatwearguedinthepreviouscase,thisimplies that ˜g()< ˜g()<0forallpairs{,}satisfying<and< ˆ.
Justasinthepreviouscase,andagainrestrictingattentiontoanappropriatesubsequenceifnecessary,wethenhavethat lim
→−∞˜g
()=0.Since ˜g()<0forall< ˆ,thisimpliesthatforsomesufficientlysmall ¯itmustbethat
˜g( ¯)[1+ ˜g( ¯)]≤0 (.10)
whichdirectlyimpliesthat ˜g cannotbeasolutionto(.8).
24 Anothersolutionis,forexample, ˆg()=b[W (e1−/b)+1]whereWistheso-calledLambertWfunctionwhichisimplicitlydefinedby=W
eW(). Thefunction ˆgsatisfies ˆg (0)=2b(whichcanbeinterpretedastheinitialcondition).Thefunction ˆgthereforegivesrisetoanotherfullyrevealingequilibrium inwhichtheinformedDM’spolicyis˛ˆ1(,0)= ˆg()++b.Itisalsoeasytocheckthatthereareinfinitelymanyothersolutionsgtothedifferentialequation in(.8).Suppose ¯gisasolutionto(.8).Fixanddefine ˜gbyletting ˜g()= ¯g(+)forevery.Then ˜gisalsoasolution.LemmaA.1. ConsiderthecaseofIdeologicalBias.SupposethatDM2sets=1andDM2chooses˛1andoptimally.Thenby
choosinga2(m)=E()foreverym,DM2achievesanoverallexpectedpayoffof−b2−Var().25
Proof. GiventhatDM2chooses=1,DM1’schoiceofa1willnotbeobservedbyDM2.Hence,from(1)itisevidentthatit
isoptimalforDM1toseta1=+bforevery ∈R.HenceDM2’sfirstperiodexecutedpayoffis−b2.Againdirectlyfrom(1),
ignoringmandsettinga2=E(),itisclearthatDM2canachieveasecond-periodexpectedpayoffofVar().
LemmaA.2. ConsiderthecaseofIdeologicalBias.InanyequilibriuminwhichDM2sets=0heroverallexpectedpayoffis boundedaboveby−4b2.
Proof. FromProposition1weknowthatsuchequilibriummustentailachoiceofd=PA,andmustbefullyrevealing.Hence DM2willbeabletoinferfromobservinga1.Therefore,from(1),DM2willchoosea2=forevery,andhenceachievea
secondperiodexpectedpayoffof0.This,ofcourse,isDM2’sgloballyoptimalexpectedpayoffinthesecondperiod. FromProposition2weknowthatDM2’soverallpayoffcannotbeabovetheonesheobtainsinthelinearequilibriumin whichDM1setsa1=+2bforevery ∈R.ThisgivesDM2afirstperiodexpectedpayoffof−4b2.
ProofofofProposition3. Let ¯b=
Var()/3.Notethatthistriviallyimpliesthatforeveryb> ¯bwemusthavethat −4b2<−b2−Var(),andforeveryb≤ ¯b wehavethat−4b2≥−b2−Var().Weprovepartifirst.Suppose,bywayofcontradiction,thatb> ¯bandthatthereexistsanequilibriuminwhichDM2 chooses=0.ByLemmaA.2,insuchaputativeequilibriumDM2’spayoffisboundedaboveby−4b2.ByLemmaA.1,by
deviatingandsetting=1,DM2willachieveapayoffthatisboundedbelowby−b2−Var().Thisisevidentlyaprofitable
deviationfromtheputativeequilibriumandhencetheproofofpartiisnowcomplete.
Nowfortheproofofpartii.Letanyb≤ ¯b begiven,andconstructanequilibriumasfollows.DM2chooses=0,and followingthischoice,on-path,thelinearequilibriumofProposition2isplayed.IfDM2deviatesandsets=1,ababbling equilibriumisplayedinwhichDM1choosesafixed ¯m regardlessofandDM2choosesa1=E().DM2’spayoffintheproposed
equilibriumis−4b2.Ifinsteadhedeviatesandsets=0hispayoffis−b2−Var().Sinceb≤ ¯b thisisnotaprofitabledeviation
andhencetheproofofpartiiisnowcomplete.
PreliminaryresultsfortheproofofProposition4.BeforeproceedingwiththeproofofProposition4,weletϕdenote theprobabilitythat ∈[, ¯]asrequiredbyDefinition1.
DefinitionA.1. Boundedpartitional:Ancontinuationequilibriumofthegamefollowing=1isboundedpartitionalifand onlyifDM1’sstrategypartitionsthesetofpossible(namelyR)intodisjointintervals(overwhichthemessagedoesnot change),andthelengthofsuchintervalsisboundedawayfromzero.
LemmaA.3. Foranyb>0,allcontinuationequilibriaofthegamefollowing=0areboundedpartitional.
Proof. ThisisastraightforwardadaptationofargumentsinCS(tothecaseof ∈Rratherthanaboundedinterval),and thedetailsareomitted.
LemmaA.4. SupposethatAssumption 1holds.Letadecreasingsequenceofstrictlypositivebiasparameters{bk}∞k=0 with
lim
k→∞bk=0begiven.
Consideranysequenceofassociatedcontinuationequilibriaofthegamefollowing=1,andletV2k∗ bethesequenceofassociated payoffsforDM2.
AssumethatthatforeveryktheequilibriumstrategyofDM1partitions[, ¯]intoatmosttwosets(atmosttwodistinct messagesaresentinequilibriumasrangesover[, ¯]).
Then,thereexistsa ¯ksuchthatforeveryk≥ ¯k,wehavethatV2k∗ <−4b2 k.
Proof. Letabbegiven.ConsiderastrategyforDM1thatentailssendingeitheroneortwomessagesasrangesover[, ¯]. Supposeonlyonemessageissent,say ˆm.Conditionalon ∈[, ¯],DM2’spayoffisthenboundedaboveby−Var(| ∈[, ¯]). Supposenextthatonlytwomessagearesent,say ˆm and ˆˆm.ThenthepayofftoDM2isboundedaboveby−Var(| ∈ [, ¯]andm= ˆm)−Var(|∈[, ¯]andm= ˆˆm).Notethattheseboundsdonotdependonb,butonlyonthedistributionof .Letthebestpossibleboundbedenotedby− (with >0).ThenifDM1onlysendsoneortwomessagesasrangesover [, ¯]thesecondperiodpayofftoDM2isboundedaboveby− ϕ.ThisisbecauseDM2’spayoffconditionalon∈/[, ¯]isat most0.Sinceinanycontinuationequilibriumofthegamefollowing=1,DM1obviouslychoosesa1=+b,DM2’spayoff
inanysuchequilibriumis−b2.Hence,wecanconcludethatifDM1onlysendsoneortwomessagesasrangesover[, ¯]
inanycontinuationequilibriumofthegamefollowing=1,theoverallpayofftoDM2isboundedaboveby−b2− ϕ.
Since− ϕ doesnotdependonb,forbsufficientlysmallitisevidentthat −b2− ϕ<−4b2.Theclaimthen follows
immediately.
ProofofofProposition4. Bywayofcontradictionassumethatthereexistsadecreasingsequenceofbiasparameters {bk}∞k=0withklim→∞bk=0,suchthatforeachbkinthesequencethemodelhasaFIPEinwhichDM2actuallychooses=1.
NoticefirstthatbyPropositions1and2weknowthatinanyFIPEtheplayers’strategiesconditionalon=0giveriseto thelinearequilibriumofProposition2andhenceyieldapayoffofV2k∗ =−4b2
ktoDM2.
ByLemmaA.4,itmustbethat,contingenton=1,foreverykinthesequence(discardtheinitialelementsifnecessary) DM1’sstrategyinvolvessendingatleastthreedifferentmessagesasrangesover[, ¯].
OurnextendeavoristocomputeanupperboundtoDM2’spayoffcontingenton=0–orequivalentlyinthecontinuation equilibriumofthegamefollowing=1.
Foranygivenbk,considerthepartitionofthesetofpossible(namelyR)inducedbyDM1’sstrategy(seeLemmaA.3).
Considertheleft-mostcellofsuchpartitionsuchthatitsupperboundisnosmallerthan.Letsuchboundbedenotedbydk.
Considernexttheright-mostcellofsuchpartitionsuchthatitslowerboundisnolargerthan ¯.Letsuchboundbedenoted by ¯dk.Withoutlossofgenerality(bytakingsubsequencesifnecessary)weassumethatbothsequences{dk}∞k=0and{¯dk}
∞ k=0
convergeask→∞.
Noticenextthatitmustbethecasethat lim
k→∞( ¯dk−dk)=>0 (.11)
Thisissimplybecauseotherwisewecouldobtainacontradictionusingthesameargument(inthelimit)asintheproof ofLemmaA.4.Letkbetheprobabilitythat ∈[dk, ¯dk]and lim
k→∞k=.NotethatbyAssumption1itmustbethat=
ϕ/( ¯−)andhence>0.
Noticethatatthispointweknowthatcontingenton ∈[dk, ¯dk],thecontinuationequilibriumofthegamefollowing
=1isexactlythemodelinCSinthespecialcaseofauniformdensity.26
LetU(dk, ¯dk,b
k)beDM2’ssecondperiodpayoffunderthemostinformative(theonethatgivesDM2thehighestpayoff),
contingenton ∈[dk, ¯dk].Overall,DM2’sequilibriumpayoffinthecontinuationequilibriumofthegamefollowing=1is
thenboundedaboveby −b2
k+kU(dk, ¯dk;bk) (.12)
ThisissimplybecauseDM2’sfirstperiodpayoffinanyequilibriumofthecontinuationequilibriumofthegamefollowing =1is−b2
kandwhenever∈/[dk, ¯dk]DM2’ssecondperiodpayoffobviouslycannotexceed0.
Ourcontradictionhypothesisand(.12)implythatthereexistsn∈Nsuchthatforeveryk≥n, −b2 k+ 2U(dk, ¯dk,bk)≥−4b 2 k (.13) whichimplies U(dk, ¯dk;bk)≥−6b 2 k (.14)
DirectlyfromCSintheconstantdensitycase27wegetthat
U(dk, ¯dk,bk)=−Akb2k−Bk (.15)
forsomepositiveAkandBk.AlsodirectlyfromCS,thereexistsm∈Nsuchthatforeveryk≥mwehavethatAk>6/.Hence,
fork≥max{n,m}itmustbethat U(dk, ¯dk,bk)=−Akb2k−Bk<−
6b2 k
(.16)
whichcontradictsinequality(.14)andhenceconcludestheproof
WecontinuewithapreliminaryresultthatwillbeusedtoproveProposition5.
LemmaA.5. ConsidertheAgencyBiascase.IfthereisanyequilibriuminwhichDM2chooses=0,thenthereisanequilibrium asfollows.
(i)DM2chooses=0.
(ii)DM1’schoiceofpolicyisgivenby˛1(0,)=.
(iii)ThepayoffsassociatedwiththisequilibriumPareto-dominatethoseofallotherequilibriainwhichDM2chooses=0. WewillrefertothisasthelinearequilibriumunderAgencyBias.
26 CSconsiderexplicitlythecaseofauniformlydistributedover[0,1].Anappropriatescalefactorneedstobefactoredintoconformtothe(sub-)model wehavehere.