美國小型和大型商業(yè)銀行的利潤效率來源及差異及引力波的實(shí)驗(yàn)探測(cè)給我們的啟示

本科畢業(yè)論文外文翻譯外文題目：ProfitefficiencysourcesanddifferencesamongsmallandLargeU.Scommercialbanks出處：Journalofeconomicandfinance(2021):289-299作者：AigbeAkhigbeandJamesMcNulty原文：IntroductionScaleeconomiesinbankinghavelongbeenofinteresttofinancialeconomists,andthisinteresthasbeenheightenedinrecentyearsbytwodevelopments.Thefirstisincreasedconcernaboutthesurvivabilityofsmallcommunitybanksinaneraofbankconsolidation.ThisthemewasthesubjectofaMarch2021conferenceattheFederalReserveBankofChicagoandformedthebasisforaspecialMarch2021issueoftheJournalofFinancialServicesResearch.Theseconddevelopmentisrecentacademicresearchsuggestingthatsmallbanksmayhavebothaninformationadvantageoverlargebanks,asinNakamura(1993),Mester,Nakamura,andRenault(2021),andCarterandMcNulty(2021),andanincentivetousethisinformationadvantageinthelendingprocess.Bergeretal.(2021)provideevidenceonthesecondpoint.Theysuggestthatsmallbanksmayhaveacomparativeadvantageindevelopingandusingthe“soft”informationoftenassociatedwithsmallbusinesslending.PROFEFFisaneconometricfinancialperformancemeasurethatindicateshowactualfinancialperformancecomparestoatheoreticalbest-practicefrontier.Consideringdifferencesin,andsourcesof,profitefficiency(PROFEFF)bybanksizegroupscanhelpshedlightontheissueofwhichbanksusetheircapitalmoreefficiently(providedprofitsarenormalizedbyequity,whichistheapproachwetakeinthispaper).RelevantLiteratureandEstimationIssuesMoststudiesdoneinthe1980sandearly1990ssuggestthatscaleeconomiesareslightornonexistentbeyondassetsizesof$50to$100million.SomeearlyexamplesareBenston,Hanweck,andHumphrey(1982),Gilligan,Smirlock,andMarshall(1984),Clark(1984),Nelson(1985),andBerger,Hanweck,andHumphrey(1987).Using1984data,BergerandHumphrey(1991)findthateconomiesofscaleatthefirmlevelareexhaustedbeyond$200millioninassetsize.Sincethisinfluentialstudy,whichfoundthatgainsfromreducingcostinefficienciesdominategainsfromrealizingscaleeconomies,thefocusofmoststudieshasshiftedtoinefficienciesandhenceawayfromoptimumsize.However,usingcostefficiency,BergerandMester(2021)concludethatscaleeconomiesareexhaustedwellbefore$10billioninassetsize.Sincethesestudiesestimatecosteconomies,theycannotdirectlyaddressthepossibilitythatrevenuesmaybemorethanproportionatelyhigherforlargerbanks.However,anotherrelatedtrendinthisliteraturehasbeenincreasedrecognitionthatprofitefficiencyisamoreappropriatetechniquetouseinevaluatingbankperformancethancostefficiencysincePROFEFFincorporatesbothrevenuesandcosts.RecentprofitefficiencystudiesincludeAltunbas,Evans,andMolyneux(2021),AkhigbeandMcNulty(2021),BergerandMester(2021,2021),DeYoungandHasan(2021),andDeYoungandNolle(1996),amongothers.OtherrecentstudiesofU.S.bankingefficiencyincludeBarr,Kilgo,Siems,andStiroh(2021),Zimmel(2021),BergerandDeYoung(2021),andWheelockandWalker(2021,2021).Thekeynotepaperattheabove-mentionedconference,byDeYoung,Hunter,andUdell(2021),arguesthatsmallbanksandlargebankshaveadifferentfocusandadifferentbusinessmodel—personalizedserviceandcustomizedfinancialservices(e.g.,smallbusinessloans)inthecaseofsmallbanksandefficientdistributionofrelativelyuniformtypesoffinancialservices(e.g.,creditcardsandhomeequityloans)inthecaseoflargebanks.Thebusinessmodelofthesmallbankrequiresrelativelyhighcost,whilelargerbankscankeepcostlow.Underthislineofreasoning,bothtypesofbanksshouldhavearoletoplayinthefuturefinancialservicesmarketplace.Nonetheless,differencesinPROFEFFareimportantbecauseultimatelysmallandlargebankscompeteforcapital.Forexample,thedecisionofasmallerbanktojoinornottojoinalargebankingorganizationthroughamergerisultimatelyasubjectivedecisionabouthowitscapitalcanbebestemployed.Giventheseconsiderations,twoimportantquestionsraisedbyBergerandMester(2021)mustbeconsideredbeforeweproceed.Thefirstistheappropriatevariable—assetsorequity—touseinnormalizingprofitsincomputingthePROFEFFmeasure.Thesecondistheuseofonefrontierorseveralfrontiersincomparingbanksofdifferentsizes.BecausePROFEFF,whennormalizedbyequity,measureshowwellabankutilizesitsfinancialcapital,wechoosetousethismeasure.Someearlierstudiescomparinglargeandsmallbanks,suchasAkhigbeandMcNulty(2021),useassetsandfindsmallbankshavehigherPROFEFF.Useofequitycanbeexpectedtoproducetheoppositeresultsincelargebanksusemoreleveragethansmallbanks.Inotherwords,thePROFEFFmeasurethatweuseisclosertoreturnonequity,whichshouldshowgreaterPROFEFFforlargebanks.Normalizingbyassetsislikelytoproducetheoppositeresult.SincewewanttoconsiderthesourcesofthedifferencesinPROFEFF,weusethreedifferentfrontiersforsmall,medium,andlargebanks.Thisisconsistentwiththeassumptionthattheirfocus,andtheirbasicbusinessmodel,isdifferent.ThisprocedureallowsthePROFEFFmeasurestohavemaximumflexibility—smallbankPROFEFFanditsfrontierarenotconstrainedoraffectedinanywaybytheactivitiesandbalance-sheetstructureoflargebanks,andviceversa.Thus,whenwelookatthedeterminantsofPROFEFFforthethreegroups,iftheyaredifferent,thiswillreflectrealdifferences,andiftheyarethesame,itwillnotbebecausethesamefrontierwasimposedonallbanks.Werecognizethealternativeargumentthat,incomparingtheperformanceofdifferentbanks,onenormallywantstousethesametest,nottwoorthreedifferenttests.(Wemadethisargumentourselvesinanearlierpaper.)ProfitEfficiencyTrendsforVariousBankSizeGroupsPROFEFFhasdeclinedsharplyinrecentyearsforsmallbanks,from0.778in1995to0.702in2021.Weconsiderthehypothesisthatthisdeclinemayreflectanincreasingnumberofdenovobanksinthesmallbankcategory.FDICdataindicatethatbetween1992and1994only74newbanksperyearwerechartered,whichnodoubtreflectsthedepressedstateofthebankingindustryatthattime.Incontrast,inthesixyearperiodfrom1995to2021,therewereanaverageof175newbankchartersperyear.Manyofthesebanksremainsmallforanumberofyearsafterbeingchartered.DeYoungandHasan(2021)showthatdenovobanksaremuchlessprofitefficientthanolder,similarlysizedbanks.InTable1thepercentofbanksintheunder$100milliondollarcategorythataredenovos(ageunder10years)hasincreasedfrom11.4percentto13.5percent.Moreover,DeYoungandHasan(2021)showthatthefirstthreeyearsofoperationsshowparticularlylowPROFEFFfornewbanks.Thegreaterdispersionofthedataforsmallbanksinrecentyearsalsosupportsthisexplanation.Thus,thehypothesisthatatleastpartofthedeclineinsmallbankPROFEFFbetween1995and2021reflectstheperformanceofthedenovobanksinthesampleappearsreasonable.Incontrasttothesmallbanks,PROFEFFisrelativelystableformedium-sizeandlargebankswhentrendsinbothmedianandmeanvaluesaretakenintoaccount.Forexample,meanPROFEFFformediumsizebanksremainsabove0.81throughouttheperiodandlargebankPROFEFFremainsabove0.84.Nonetheless,somedeclineisevidentintheestimates,whichprobablyreflectsinpartthefactthatbanksinallsizegroupsareusinglessleveragebecauseofpressuresfromregulatorstoincreasetheamountofequitycapitalontheirbalancesheet.ResultsoftheRegressionAnalysisoftheCorrelatesofProfitEfficiencyAsnoted,weconsiderdifferencesinthesignificanceofthecorrelatesamongthesizegroupsasanindicationthatbanksofdifferentsizeshavedifferentwaysofachievinghighprofitability.Theequity/assetsratio(EQUITY)isnegative(asexpected)andsignificantatmediumandlargebanks.Thisindicatesthat,withinthesesizegroups,themoreprofit-efficientbanks,ceterisparibus,usemoreleverage(lessequity)thantheotherbanksinthesamesizegroup.Ageispositiveandsignificantforsmallandmedium-sizebanksbutnotforlargeones.Thiswouldbeconsistentwiththenotionthattheestablishmentofastrongcreditcultureisanimportantelementinsmallandmedium-sizebankprofitability.Overlappinggenerationsofloanofficers(eachgenerationtrainingthenextintheartofmakingloansinthelocalcommunity)andrelationshipdevelopmentareimportantelementsindevelopingsuchaculture.Successfulimplementationofthesestrategieswouldrequirethatthebankbeinexistenceforaconsiderableperiodoftime.Thisisthe“l(fā)earningbydoing”discussedbyBergerandMester(2021)andmentionedabove.Themarketplacenonperformingloanratio(MKTNPL)issignificantwiththeexpectednegativesignforsmallandmedium-sizedbanksbutisactuallypositiveforlargebanks.Thisratioisnotparticularlyrelevantforlargerbankssinceitonlyconsidersnonperformingloansinthecountywherethehomeofficeofthebankislocated;mostlargebankshaveofficesandloansinmorethanonecounty.Membershipinamultibankholdingcompany(MBHC)isnegativeandsignificantforsmallandmedium-sizebanksbutnotforlargeones.Apparentlythemostsuccessfulsmallandmediumsizedbanksareindependent.Italsosuggeststhatlargebanksthataremembersofholdingcompaniesarelesslikelytobeaffectedbydevelopmentsattheholdingcompanylevelthanarethesmallerandmedium-sizedholdingcompanymembers.Therelativenonperformingloanratio(RELNPL)issignificantandnegativebutonlyformedium-sizebanks.Differencesinfeerevenue(FEEREV)areanimportantsourceofdifferencesinprofitabilityatsmallandmedium-sizebanks(notetheveryhighsignificancelevels)butnotatlargerones.Themostlikelyexplanationforthisisthatvirtuallyalllargebanksdependonfeerevenueratherthanthatfeerevenueisunimportantforthesebanks.[SeeTable1.]Theyeardummyvariablesarealsosignificantforsmallandmedium-sizebanksonly.Thissuggeststhatlargerbankshavemoreconsistentprofitabilityovertimethantheotherbanks.Competitiveconditionsmatterbutonlyforthetwosmallersizegroups.DifferencesinPROFEFFamongsmallbanksarepositivelyrelatedtotheHHI.Inotherwords,ceterisparibus,PROFEFFishigherinmoreconcentratedmarkets,whichisexactlywhatwewouldexpect.Thesamerelationshipholdsformedium-sizebanksbutnotforlargeones.BergerandMester(2021)andAkhigbeandMcNulty(2021)alsofindapositiverelationshipbetweenPROFEFFandtheHHI.Inaddition,mostofthecoefficientsoftheothercorrelatesareconsistentwiththefindingsofAkhigbeandMcNulty(2021).Thefactthatbanksofdifferentsizeattainhigh(orlow)profitefficiencythroughdifferentmeansisconsistentwiththeabove-mentionedrecentanalysisofDeYoung,Hunter,andUdell(2021)thatsuggeststhatbanksofdifferentsizeshavedifferentbusinessmodels.SummaryandConclusionsWeexaminethedifferencesinprofitefficiencyatsmall(under$100millioninassets),mediumsize($100millionto$1billion)andlarge(morethan$1billion)banksfortheperiod1995to2021,andwealsoexaminethesourcesofthesedifferences.SincewecalculatePROFEFFnormalizedbyequity,itisnotsurprisingthatlargebanksrankhighest.However,thedifferencesarequitelarge.Fortheperiodasawhole,averagePROFEFFis0.752forthesmallbanks,0.823forthemedium-sizebanks,and0.856forthelargebanks.Inotherwords,thedifferencebetweensmallandlargeismorethan10basispoints,whichiseconomically(andstatistically)quitesignificant.SmallbankscanattainhighPROFEFFbybeingolder,byoperatinginmarketswithlowdefaultrates,bybeingindependentofaholdingcompany,bygeneratinghighfeeincome,byoperatinginaconcentratedmarket,andbyhavingmoreoftheirassetsinloansasopposedtosecurities.LargebanksthathavehighPROFEFFdosoprimarilybyusingmoreleveragesincenoneoftheothervariablesaresignificant.DeYoung,Hunter,andUdell(2021)arguethatdifferenttypesofbankshavedifferentbusinessmodels.Thebusinessmodelofthesmallbankiscustomizedandpersonalizedservicebutathighcost,whilelargerbanksaimtodeliverrelativelyuniformfinancialservicestolargegroupsofcustomersatlowercost.Ouranalysisisconsistentwiththisnotionthatdifferenttypesofbanksattainhighprofitabilityindifferentways.譯文：美國小型和大型商業(yè)銀行的利潤效率來源及差異簡介金融經(jīng)濟(jì)學(xué)家一直對(duì)銀行的規(guī)模經(jīng)濟(jì)很感興趣，近幾年，由于兩次發(fā)展而對(duì)銀行規(guī)模經(jīng)濟(jì)的這個(gè)興趣進(jìn)一步的加深。首先是增加對(duì)銀行合并時(shí)代的小型社區(qū)銀行的關(guān)注。這個(gè)主題是在2021年3月的一個(gè)美國芝加哥聯(lián)邦儲(chǔ)蓄銀行會(huì)議的主題，形成了一個(gè)2021年3月的特殊的金融服務(wù)研究雜志的基礎(chǔ)。第二個(gè)發(fā)展是最近的學(xué)術(shù)研究，表明了小銀行可能比大銀行更有信息的優(yōu)勢(shì)（1993），同在中村，美斯特，中村，雷諾（2021），卡特和麥克納爾蒂（2021年），鼓勵(lì)使用貸款過程中的這種信息優(yōu)勢(shì)。柏格等（2021）提供了第二點(diǎn)證據(jù)，他們認(rèn)為，小型銀行在發(fā)展和利用“軟”信息時(shí)可能具有的一個(gè)比較優(yōu)勢(shì)往往與小企業(yè)貸款相關(guān)。利潤效率是指示如何比較實(shí)際財(cái)務(wù)業(yè)績和最佳實(shí)踐前沿理論的計(jì)量財(cái)務(wù)績效的衡量?？紤]到差異以及來源，銀行規(guī)模組的盈利效率可以幫助解決銀行更有效的使用他們的資本的這個(gè)問題（提供的利潤歸一股權(quán)，這是我們?cè)诒疚牟扇〉姆椒ǎＯ嚓P(guān)的文獻(xiàn)和估計(jì)問題在80年代和90年代初所做的大多數(shù)研究表明，資產(chǎn)規(guī)模在5000萬美元至1億美元的規(guī)模經(jīng)濟(jì)是輕微的或是不存在。利用1984年的數(shù)據(jù)，伯杰和漢弗萊（1991）發(fā)現(xiàn)資產(chǎn)規(guī)模在2億美元以上的規(guī)模經(jīng)濟(jì)在企業(yè)層面已經(jīng)枯竭。由于這個(gè)有影響力的研究，從而發(fā)現(xiàn)從降低成本的低效率的收益來主宰實(shí)現(xiàn)規(guī)模經(jīng)濟(jì)的收益。大多數(shù)研究的焦點(diǎn)已經(jīng)轉(zhuǎn)移到低效率，從而遠(yuǎn)離了最佳規(guī)模。但是，使用成本效益，伯杰和美斯特（2021）的結(jié)論是規(guī)模經(jīng)濟(jì)用盡之前的資產(chǎn)規(guī)模是100億美元。由于成本經(jīng)濟(jì)的估計(jì)研究，他們不能直接解決大型銀行可能有比例較高的收入問題的可能性。然而，這些文獻(xiàn)中的另一個(gè)相關(guān)趨勢(shì)已進(jìn)一步的認(rèn)識(shí)到，利潤效率使用在銀行業(yè)績?cè)u(píng)價(jià)中比成本效益更合適，因?yàn)槔麧櫺始劝杖胗职M(fèi)用。近期的利潤效率研究包括Altunbas,Evans,和Molyneux(2021),Akhigbe和McNulty(2021),Berger和Mester(2021,2021)DeYoung和Hasan(2021)和DeYoung和Nolle(1996)等。最近其他的美國銀行效率的研究包括了Barr，Kilgo，Siems和Stiroh（2021），Zimmel（2021），Berger和DeYoung（2021）和Wheelock和Walker（2021,2021）.DeYoung,Hunter和Udell（2021）在上述會(huì)議主題文件中認(rèn)為，小型銀行和大型銀行有著不同的重點(diǎn)和不同的商業(yè)模式——小銀行的情況是個(gè)性化服務(wù)和客制化的金融服務(wù)（例如，小企業(yè)貸款），而相對(duì)于大型銀行來說則是分布比較均勻類型的高效金融服務(wù)（例如，信用卡和房屋凈值貸款）。小型銀行的業(yè)務(wù)模式需要的成本相對(duì)較高，而大銀行可以保持低成本。根據(jù)這種推論，這兩種類型的銀行在未來金融服務(wù)市場(chǎng)上都有一個(gè)發(fā)揮的角色。然而，在利潤效率中的差異是很重要的，因?yàn)樽罱K小型銀行和大型銀行競爭的是資本。例如，一個(gè)較小的銀行決定通過合并加入或者不加入一個(gè)大型的銀行機(jī)構(gòu)，最終是關(guān)于它們的資本如何能最好使用的主觀決定。鑒于這些因素，由美斯特和伯杰（2021）提出的兩個(gè)重要問題在我們開始之前必須考慮。第一個(gè)是相應(yīng)的變量——資產(chǎn)或權(quán)益——使用正常化利潤計(jì)算利潤效率的措施。第二個(gè)則是利用一個(gè)或者幾個(gè)前沿領(lǐng)域比較不同規(guī)模的銀行。由于利潤效率，股權(quán)歸一時(shí)，一個(gè)銀行如何利用好它們的金融資本的措施，我們選擇使用這項(xiàng)措施。一些早期的研究利用資產(chǎn)比較大型和小型銀行的，例如Akhigbe和McNulty（2021），發(fā)現(xiàn)小銀行具有較高的利潤效率。利用股權(quán)可預(yù)期產(chǎn)生相反的結(jié)果，因?yàn)榇笮豌y行比小銀行有更好的杠桿作用。換句話說，我們使用的利潤效率的措施更接近凈資產(chǎn)收益率，這表現(xiàn)出大型銀行有更大的利潤效率。資產(chǎn)正?；赡墚a(chǎn)生相反的結(jié)果。由于我們要考慮利潤效率差異的來源，我們使用小型，中型和大型銀行的三個(gè)不同的領(lǐng)域。這與假設(shè)一致，它們的焦點(diǎn)，它們的基本經(jīng)營模式是不同的。這個(gè)程序允許利潤效率措施有最大的靈活性——小銀行的利潤效率不受大銀行的活動(dòng)和資產(chǎn)負(fù)債表結(jié)構(gòu)的任何約束或影響，反之亦然。因此，當(dāng)我們看到這三個(gè)群體的利潤效率的決定因素，如果它們是不同的，這將反應(yīng)真正的差別，如果它們是相同的，所有的銀行將不會(huì)因?yàn)橄嗤那把乇恢撇?。我們認(rèn)識(shí)到的另一類說法是，在比較不同銀行的業(yè)績時(shí)，人們通常想要使用相同的測(cè)試，而不是兩個(gè)或者三個(gè)不同的測(cè)試。（先前的文章中我們自己討論過這個(gè)論點(diǎn)）各種規(guī)模的團(tuán)體銀行的利潤效率趨勢(shì)近幾年來，小型銀行的利潤效率急劇下降，從1995年的0.778下降到2021年的0.702。我們認(rèn)為這種下降的假設(shè)可能反映了在小銀行類別中的從頭銀行數(shù)量的增加。聯(lián)邦存款保險(xiǎn)公司的數(shù)據(jù)表明，在1992年和1994年之間，每年只有74家特許的新銀行，這無疑反映了當(dāng)時(shí)銀行業(yè)的低迷狀態(tài)。與此相反，在從1995年至2021年的六年時(shí)間里，平均每年有175家特許成立的銀行。許多銀行在特許成立之后的很多年規(guī)模仍然很小。DeYoung和Hasan（2021）表明，從頭銀行的利潤效率比老的，相同規(guī)模的銀行的利潤效率少得多。表1中在一億美元以下的銀行類別的百分比中從頭銀行（未滿10年）已經(jīng)從百分之11.4上升到百分之13.5。此外，DeYoung和Hasan（2021）指出，新銀行前三年的經(jīng)營顯示出的利潤效率特別低。近幾年，數(shù)據(jù)更加分散的小銀行也支持這個(gè)解釋。因此，在1995年至2021年的小型銀行至少部分利潤效率下降的假設(shè)反映了從頭銀行在樣本中出現(xiàn)的合理性。與小型銀行相反，當(dāng)把中位數(shù)和均值的趨勢(shì)都考慮在內(nèi)時(shí)，中型銀行和大型銀行的利潤效率相對(duì)穩(wěn)定。舉例來說，意味著在整個(gè)期間內(nèi)中型銀行的利潤效率高于0.81而大型銀行的利潤效率仍高于0.84。然而，在估計(jì)中有所下降是顯而易見的，這可能在某種程度上反映了一個(gè)事實(shí)，銀行在所有規(guī)模團(tuán)體中較少使用杠桿是因?yàn)閬碜员O(jiān)管機(jī)構(gòu)的壓力增加了他們的資產(chǎn)負(fù)債的資本金額。利潤效率的回歸的相關(guān)性分析結(jié)果如前所訴，我們考慮相關(guān)的意義之間差異的大小作為一組相關(guān)指示，不同規(guī)模的銀行有不同的方式來實(shí)現(xiàn)高盈利的能力。在中型和大型銀行中股本/資產(chǎn)的比率（股權(quán)）為負(fù)的（如預(yù)期），而且是顯著的。這表明了，在其他條件不變時(shí)，更多利潤，高效率的銀行在這些相同的大小團(tuán)體中比其他的銀行使用了更多的杠桿（較少的權(quán)益）。對(duì)于小型銀行來說年齡是積極的，重要的，但是對(duì)大型銀行而言不是。這是個(gè)一致的概念，一個(gè)強(qiáng)有力的信用文化的建立是中小銀行盈利的重要因素。信貸員的世代重疊（在當(dāng)?shù)厣鐓^(qū)，每一代的培訓(xùn)下發(fā)放貸款）和關(guān)系的發(fā)展，是建立這樣一種文化的重要元素。這些戰(zhàn)略的成功實(shí)施將要求銀行存在相當(dāng)長的時(shí)間。這就是美斯特（2021）討論的“從做里面學(xué)習(xí)”，如上所訴。中小銀行的不良市場(chǎng)貸款率（MKTNPL）是顯著的，與預(yù)期的一樣是負(fù)的，但是實(shí)際上對(duì)于大銀行來說是正的。這個(gè)比例對(duì)較大的銀行來說不是特別重要，因?yàn)樗鼉H考慮家庭辦公所在地縣級(jí)那里的銀行的不良貸款。多數(shù)的大銀行有一個(gè)以上的縣辦事處和貸款。對(duì)于中小銀行來說，會(huì)員在一家銷售控股公司（MBHC）是具有消極的意義和作用的，但對(duì)于大銀行來說不是。顯然，最成功的中小銀行是獨(dú)立的。它還表明了，大型銀行控股公司的成員不太可能受到控股公司發(fā)展水平的影響，而中小銀行控股公司的成員可能受到的影響較大。相對(duì)的不良貸款比例（RELNPL）是顯著的復(fù)數(shù)，但僅僅是對(duì)中型銀行而言。在中小銀行中，費(fèi)用收入的差異是盈利能力差異的一個(gè)重要來源（注意顯著性水平非常高），但是對(duì)于大型銀行來說不是。對(duì)此最可能的解釋是，幾乎所有大型銀行都依賴費(fèi)用收入，而不是說費(fèi)用收入對(duì)這些銀行不重要。(見附表1)年的虛擬變量也只對(duì)中小銀行具有重要的意義。這表明，隨著時(shí)間的推移大型銀行比其他的銀行具有更多持續(xù)的盈利能力。競爭條件很重要，但僅僅是對(duì)兩個(gè)較小的組織而言。小銀行之間的利潤效率的差異與赫芬達(dá)爾指數(shù)是正相關(guān)的。換句話說，在其他條件不變時(shí)，市場(chǎng)越集中，利潤效率就越高，而這也正是我們所期望的。與此有同樣關(guān)系的是中型銀行，大型銀行則不適合。BergerandMester(2021)andAkhigbeandMcNulty(2021)也發(fā)現(xiàn)了利潤效率與赫芬達(dá)爾指數(shù)之間的正相關(guān)的關(guān)系。此外，對(duì)其他大部分的相關(guān)系數(shù)的研究與AkhigbeandMcNulty(2021)的研究結(jié)果是一致的。事實(shí)上，不同規(guī)模的銀行要通過不同的方式實(shí)現(xiàn)高（或者低）的利潤效率是符合上述DeYoung,Hunter和Udell(2021)的分析的，不同規(guī)模的銀行要有不同的商業(yè)模式?？偨Y(jié)和結(jié)論我們研究了1995年至2021年期間的小型銀行（資產(chǎn)低于一億美元），中型銀行（一億美元至十億美元）和大型銀行（十億美元以上）之間利潤效率的差異，以及這些差異的來源。由于我們采用權(quán)益計(jì)算正?；睦麧櫺?，所以大銀行的排名最高也就不足為奇。但是，這些差異都相當(dāng)?shù)拇?。?duì)于整個(gè)的期間，小型銀行的平均利潤效率是0.752，大型銀行的平均利潤效率是0.823，而大型銀行的平均利潤效率0.856。換句話說，小型銀行與大型銀行的利潤效率差距超過了10個(gè)基點(diǎn)，這在經(jīng)濟(jì)上（和統(tǒng)計(jì)上）是相當(dāng)顯著的。小型銀行可以通過成長，通過低違約率的市場(chǎng)運(yùn)作，通過成為獨(dú)立的控股公司，通過產(chǎn)生高的費(fèi)用收入，通過在一個(gè)集中的市場(chǎng)中經(jīng)營和通過貸款來獲取更多自己的資產(chǎn)而不是有價(jià)證券來達(dá)到高的利潤效率。大型銀行主要是通過使用更多的杠桿來實(shí)現(xiàn)高的利潤效率，這是因?yàn)槠渌兞慷际菦]有意義的。DeYoung,Hunter和Udell(2021)指出了不同類型的銀行有著不同的商業(yè)模式。小型銀行的商業(yè)模式是客定制的和個(gè)性化的服務(wù)，但是成本高；而大型銀行的目標(biāo)則是對(duì)龐大的客戶群體在較低的成本下提供相對(duì)統(tǒng)一的金融服務(wù)。我們的分析與不同類型的銀行以不同的方式實(shí)現(xiàn)高盈利能力的這個(gè)概念是一致的。hinese

pharmaceutical

company,

jointlyannounced

the

kickoff

of

the

survey.In

about

one

month,

a

questionnaire

compiled

by

top

eye

care

medical

experts

in

China

willbe

distributed

through

multiple

online

partners,

including

H,

as

well

asthrough

offline

survey

events

held

in

universities,

middle

schools

and

primary

schools

acrossthe

country.A

report

will

be

released

based

on

the

survey

statistics

and

analysis,

and

most

importantly,guidelines

for

parents

and

youth

on

how

to

care

for

the

eyes

and

prevent

myopia

—

agrowing

problem

in

China's

digitized

society,

will

also

be

attached

on

the

report."Myopia

is

not

only

a

disease

that

makes

people

see

things

blurrily,

but

also

leads

to

severecomplications,

such

as

glaucoma

(increased

pressure

within

the

eyeball),

and

can

causeblindness,"

said

Zhou

Yuehua,

an

established

eye

care

specialist

with

Beijing

TongrenHospital."It

is

very

important

for

parents

and

children

to

know

about

the

risk

and

care

for

their

eyes."There

are

about

450

million

myopia

patients

in

China.

Among

Chinese

myopia

patients,30hinese

pharmaceutical

company,

jointlyannounced

the

kickoff

of

the

survey.In

about

one

month,

a

questionnaire

compiled

by

top

eye

care

medical

experts

in

China

willbe

distributed

through

multiple

online

partners,

including

H,

as

well

asthrough

offline

survey

events

held

in

universities,

middle

schools

and

primary

schools

acrossthe

country.A

report

will

be

released

based

on

the

survey

statistics

and

analysis,

and

most

importantly,guidelines

for

parents

and

youth

on

how

to

care

for

the

eyes

and

prevent

myopia

—

agrowing

problem

in

China's

digitized

society,

will

also

be

attached

on

the

report."Myopia

is

not

only

a

disease

that

makes

people

see

things

blurrily,

but

also

leads

to

severecomplications,

such

as

glaucoma

(increased

pressure

within

the

eyeball),

and

can

causeblindness,"

said

Zhou

Yuehua,

an

established

eye

care

specialist

with

Beijing

TongrenHospital."It

is

very

important

for

parents

and

children

to

know

about

the

risk

and

care

for

their

eyes."There

are

about

450

million

myopia

patients

in

China.

Among

Chinese

myopia

patients,30hinese

pharmaceutical

company,

jointlyannounced

the

kickoff

of

the

survey.In

about

one

month,

a

questionnaire

compiled

by

top

eye

care

medical

experts

in

China

willbe

distributed

through

multiple

online

partners,

including

H,

as

well

asthrough

offline

survey

events

held

in

universities,

middle

schools

and

primary

schools

acrossthe

country.A

report

will

be

released

based

on

the

survey

statistics

and

analysis,

and

most

importantly,guidelines

for

parents

and

youth

on

how

to

care

for

the

eyes

and

prevent

myopia

—

agrowing

problem

in

China's

digitized

society,

will

also

be

attached

on

the

report."Myopia

is

not

only

a

disease

that

makes

people

see

things

blurrily,

but

also

leads

to

severecomplications,

such

as

glaucoma

(increased

pressure

within

the

eyeball),

and

can

causeblindness,"

said

Zhou

Yuehua,

an

established

eye

care

specialist

with

Beijing

TongrenHospital."It

is

very

important

for

parents

and

children

to

know

about

the

risk

and

care

for

their

eyes."There

are

about

450

million

myopia

patients

in

China.

Among

Chinese

myopia

patients,30hinese

pharmaceutical

company,

jointlyannounced

the

kickoff

of

the

survey.In

about

one

month,

a

questionnaire

compiled

by

top

eye

care

medical

experts

in

China

willbe

distributed

through

multiple

online

partners,

including

H,

as

well

asthrough

offline

survey

events

held

in

universities,

middle

schools

and

primary

schools

acrossthe

country.A

report

will

be

released

based

on

the

survey

statistics

and

analysis,

and

most

importantly,guidelines

for

parents

and

youth

on

how

to

care

for

the

eyes

and

prevent

myopia

—

agrowing

problem

in

China's

digitized

society,

will

also

be

attached

on

the

report."Myopia

is

not

only

a

disease

that

makes

people

see

things

blurrily,

but

also

leads

to

severecomplications,

such

as

glaucoma

(increased

pressure

within

the

eyeball),

and

can

causeblindness,"

said

Zhou

Yuehua,

an

established

eye

care

specialist

with

Beijing

TongrenHospital."It

is

very

important

for

parents

and

children

to

know

about

the

risk

and

care

for

their

eyes."There

are

about

450

million

myopia

patients

in

China.

Among

Chinese

myopia

patients,30hinese

pharmaceutical

company,

jointlyannounced

the

kickoff

of

the

survey.In

about

one

month,

a

questionnaire

compiled

by

top

eye

care

medical

experts

in

China

willbe

distributed

through

multiple

online

partners,

including

H,

as

well

asthrough

offline

survey

events

held

in

universities,

middle

schools

and

primary

schools

acrossthe

country.A

report

will

be

released

based

on

the

survey

statistics

and

analysis,

and

most

importantly,guidelines

for

parents

and

youth

on

how

to

care

for

the

eyes

and

prevent

myopia

—

agrowing

problem

in

China's

digitized

society,

will

also

be

attached

on

the

report."Myopia

is

not

only

a

disease

that

makes

people

see

things

blurrily,

but

also

leads

to

severecomplications,

such

as

glaucoma

(increased

pressure

within

the

eyeball),

and

can

causeblindness,"

said

Zhou

Yuehua,

an

established

eye

care

specialist

with

Beijing

TongrenHospital."It

is

very

important

for

parents

and

children

to

know

about

the

risk

and

care

for

their

eyes."There

are

about

450

million

myopia

patients

in

China.

Among

Chinese

myopia

patients,30

a您好，為你提供優(yōu)秀的畢業(yè)論文參考資料，請(qǐng)您刪除以下內(nèi)容，O(∩_∩)O謝謝?。?！A

national

survey

was

recently

launched

to

evaluate

the

eye

health

of

Chinese

children

andteenagers.On

June

6,

China's

annual

National

Day

for

Eye

Care,

the

China

Youth

Development

ServiceCenter

and

Zhejiang

Medicine,

a

leading

listed

Chinese

pharmaceutical

company,

jointlyannounced

the

kickoff

of

the

survey.In

about

one

month,

a

questionnaire

compiled

by

top

eye

care

medical

experts

in

China

willbe

distributed

through

multiple

online

partners,

including

H,

as

well

asthrough

offline

survey

events

held

in

universities,

middle

schools

and

primary

schools

acrossthe

country.A

report

will

be

released

based

on

the

survey

statistics

and

analysis,

and

most

importantly,guidelines

for

parents

and

youth

on

how

to

care

for

the

eyes

and

prevent

myopia

—

agrowing

problem

in

China's

digitized

society,

will

also

be

attached

on

the

report."Myopia

is

not

only

a

disease

that

makes

people

see

things

blurrily,

but

also

leads

to

severecomplications,

such

as

glaucoma

(increased

pressure

within

the

eyeball),

and

can

causeblindness,"

said

Zhou

Yuehua,

an

established

eye

care

specialist

with

Beijing

TongrenHospital."It

is

very

important

for

parents

and

children

to

know

about

the

risk

and

care

for

their

eyes."There

are

about

450

million

myopia

patients

in

China.

Among

Chinese

myopia

patients,30million

are

severe

patients,

according

to

ZhouThe

prevalence

of

myopia

among

high

school

and

college

students

is

more

than

70

percent,and

the

situation

is

continuously

worsening,

he

added.Sun

Zhu,

director

with

the

China

Youth

Development

Service

Center,

said

long

hours

ofstudy,

lack

of

exercise,

especially

outdoor

activities,

and

attachment

to

electronic

screen

aresome

of

the

top

reasons

behind

the

widespread

myopia

problems,

and

the

increase

ofyounger

patients,

although

China

has

made

great

progress

in

improving

the

hardwarefacilities

and

lighting

conditions

in

schools.He

said

he

hopes

the

survey

will

alert

people

on

the

threatening

situation,

and

also

helpmedical

experts

to

better

guideline

parents

and

children's

behaviors

to

care

for

eyes,

basedon

the

timely

and

factual

statistics

the

survey

collected.A

series

of

follow-up

events

will

also

be

held

in

six

cities,

including

Jinan

in

Shandongprovince,

and

Changsha

in

Hunan

province,

to

educate

people

on

how

to

care

for

eyes

afterthe

survey

started.MoreandmoreChinesearejoggingtogetandstayfit.Mostjoggerswillrunalone,butsomewilljogwithfriendsorevencoaches.TheBeijingOlympicForestParkisoneofthemostpopularspots.Itispackedwithrunnersintheafternoon,usuallyafterwork,andatweekends.Joggingafterawholeday'sworkcanbeawaytounwind.ItistrueforHeWenjun,whoseworkplaceisrightneartheforestpark.Shediscoveredherathleticaptitudeattheageofseven,whenshebeganplayingtennis.Thensheturnedtojogging,andshehasperseveredwithitfor10years."Icometojogalmosteverydayafterwork,wheneverIhavetime.Ithinkjoggingisgoodformyhealth.Andforme,agirl,ithelpsmetoachievetoeternalgoal,tokeepslim,"Hesaid.Hesayssheprefersjoggingalone,soshecanfocusbetter.Shelovesjogging,evenduringBeijing'ssmoggydays."Ifthesmogissevere,I'llholdoffjoggingforawhile.ButifIreallywanttogetawayfromwork,I'llwearamask,orjustignorethesmogandgoonjogging,"shesaid.Forthosewhoarenotsoathletic,jogg

引力波的實(shí)驗(yàn)探測(cè)給我們的啟示摘要：引力理論的發(fā)展經(jīng)歷了數(shù)百年，從牛頓到愛因斯坦，從萬有引力定律到廣義相對(duì)論。在這過程中，科學(xué)家們引力波的預(yù)言質(zhì)疑不休、爭論不止。而引力波的實(shí)驗(yàn)探測(cè)無疑證明了一切。引力波的發(fā)現(xiàn)，彌補(bǔ)了愛因斯坦的廣義相對(duì)論的漏洞，也確定了他的理論的正確。這是人類史上出現(xiàn)的又一契機(jī)，它將為人類社會(huì)帶來重大變革?！捌莆濉笔侵袊鴤鹘y(tǒng)迎財(cái)神的日子。2016年的這一天，卻一個(gè)讓全世界物理學(xué)界沸騰的日子，甚至許多的物理學(xué)家為之痛哭流涕——被預(yù)言已經(jīng)百年的引力波，終于被探測(cè)到了。引力是什么？在今天人們所知道的物質(zhì)的四種基本相互作用中，引力作用為最弱。四種相互作用按作用強(qiáng)度比例順序是：強(qiáng)相互作用(1),電磁相互作用(10),弱相互作用(10),引力相互作用(10)。因此，在研究基本粒子的運(yùn)動(dòng)時(shí)，引力一般略去不計(jì)。但在天文學(xué)領(lǐng)域內(nèi)，由于涉及的對(duì)象的質(zhì)量極其巨大，引力就成為不僅支配著天體的運(yùn)動(dòng)，而且往往是天體的結(jié)構(gòu)和演化的決定因素。引力并不是一種所謂的“力”，而是一種屬性。牛頓在1687年出版的《自然哲學(xué)的數(shù)學(xué)原理》一書中首次提出萬有引力定律，基于此，他結(jié)識(shí)了彗星的運(yùn)動(dòng)