탅쾢늻뛔돆ꆢ막좨훆뛈낲업폫짏쫐웳튵맽뛈춶 엋쏴 뷰퇒 ꎨ커몺듳톧뺭볃랢햹퇐뺿훐탄ꆢ커몺듳톧뷰죚쾵 430072ꎩ 쓚 죝 쳡 튪 놾컄듓탅쾢늻뛔돆뗄뷇뛈돶랢ꎬ뷡뫏컒맺짏쫐웳튵쿖폐뗄막좨훆뛈낲업ꎬ퓋폃튻룶냼몬폐탅쾢늻뛔돆뫍쿖폐막좨훆뛈낲업쿂뗄막뚫쒿뇪닮틬뗈틲쯘퓚쓚뗄웳튵막좨죚춶뻶닟쒣탍ꎬ럖컶쇋컒맺짏쫐웳튵막좨죚욫뫃쿂맽뛈춶뗄탎돉믺훆ꆣ럖컶뗄뷡맻뇭쏷ꎬ벴쪹늻뾼싇탅쾢늻뛔돆틲쯘ꎬ컒맺짏쫐웳튵춬막늻춬좨ꆢ쇷춨막뇈샽욫뗍뗄막좨훆뛈낲업튲믡떼훂막좨죚쿂뗄맽뛈춶탐캪랢짺ꎻ퓚춬쪱뾼싇탅쾢늻뛔돆뫍컒맺짏쫐웳튵쳘쫢막좨훆뛈낲업뗄쟩뿶쿂ꎬ폫뷶뾼싇탅쾢늻뛔돆틲쯘뗄돉쫬횤좯쫐뎡짏춬막춬좨웳튵막좨죚쿂뗄춶탐캪쿠뇈ꎬ컒맺짏쫐웳튵막좨죚쿂맽뛈춶랢짺뗄뿉쓜탔튪듳뗃뛠ꆣ?†?맘볼듊ꎺ탅쾢늻뛔돆†?막좨훆뛈낲업†?막뚫쒿뇪닮틬†맽뛈춶??Information Asymmetries, Equity Structure Design and The Overinvestment of Listed Enterprises Pan Min &Jin Yan (Center for Economic Development Research, Faculty of Finance, Wuhan University) Abstract This paper analyses the overinvestment problems of China’s listed enterprises that have the preference of equity financing, using a equity financingꆪinvesting model based on information asymmetries and divergences of shareholders’ objectives from their special equity structure design. We show that, even if information is symmetrical, equity financing of China’s listed enterprises may cause overinvestment due to their special equity structure; and with asymmetric information and the special equity structure, the possibility of overinvestment of China’s listed enterprises is larger than those of enterprises which have asymmetric information problems only in equity financing. Keywords: information asymmetry; equity structure design; overinvestment; divergence of shareholder’s objective
ퟷ헟볲뷩 엋쏴ꎬ1966쓪짺ꎬ쓐ꎬ뫾놱뛵훝죋ꎬ죕놾짱뮧듳톧뺭볃톧늩쪿ꎬ쿖죎커몺듳톧짌톧풺뷰죚쾵뢱뷌쫚ꎬ커몺듳톧뺭볃랢햹퇐뺿훐탄볦횰퇐뺿풱ꆣ훷튪퇐뺿쇬폲캪뷰죚뺭볃톧ꆢ믵뇒틸탐톧ꆢ웳튵뷰죚폫릫쮾훎샭틔벰죕놾뺭볃폫뷰죚뗈ꆣ 뷰퇒ꎬ1974쓪짺ꎬ벪쇖죋ꎬ커몺듳톧뷰죚쾵뷰죚톧쮶쪿짺ꆣ퇐뺿랽쿲ꎺ뷰죚뺭볃톧ꆣ 1
탅쾢늻뛔돆ꆢ막좨훆뛈낲업폫짏쫐웳튵맽뛈춶 엋쏴 뷰퇒 ꎨ커몺듳톧뺭볃랢햹퇐뺿훐탄ꆢ커몺듳톧뷰죚쾵 430072ꎩ 쓚죝쳡튪ꎺ놾컄듓탅쾢늻뛔돆뗄뷇뛈돶랢ꎬ뷡뫏컒맺짏쫐웳튵쿖폐뗄막좨훆뛈낲업ꎬ퓋폃튻룶냼몬폐탅쾢늻뛔돆뫍쿖폐막좨훆뛈낲업쿂뗄막뚫쒿뇪닮틬뗈틲쯘퓚쓚뗄웳튵막좨죚춶뻶닟쒣탍ꎬ럖컶쇋컒맺짏쫐웳튵막좨죚욫뫃쿂맽뛈춶뗄탎돉믺훆ꆣ럖컶뗄뷡맻뇭쏷ꎬ벴쪹늻뾼싇탅쾢늻뛔돆틲쯘ꎬ컒맺짏쫐웳튵춬막늻춬좨ꆢ쇷춨막뇈샽욫뗍뗄막좨훆뛈낲업튲믡떼훂막좨죚쿂뗄맽뛈춶탐캪랢짺ꎻ퓚춬쪱뾼싇탅쾢늻뛔돆뫍컒맺짏쫐웳튵쳘쫢막좨훆뛈낲업뗄쟩뿶쿂ꎬ폫뷶뾼싇탅쾢늻뛔돆틲쯘뗄돉쫬횤좯쫐뎡짏춬막춬좨웳튵막좨죚쿂뗄춶탐캪쿠뇈ꎬ컒맺짏쫐웳튵막좨죚쿂맽뛈춶랢짺뗄뿉쓜탔튪듳뗃뛠ꆣ??맘볼듊ꎺ탅쾢늻뛔돆†?막좨훆뛈낲업†?막뚫쒿뇪닮틬†맽뛈춶?? 튻ꆢ컊쳢뗄쳡돶 뛠쓪살ꎬ컒맺짏쫐웳튵췢늿뷰죚뫍죚뷰엤훃랽쏦뗄쿔훸쳘헷쫇웳튵뗄막좨죚욫뫃뫍막좨죚뷰엤훃킧싊뗄뗍쿂ꆣ훚뛠뗄톧헟듓샭싛뫍쪵횤솽룶랽쏦럖컶뫍첽쳖쇋컒맺짏쫐웳튵뗄막좨죚욫뫃컊쳢ꆣ뛸뛔폚막좨죚욫뫃쿂뗄웳튵죚뷰엤훃킧싊뗍쿂컊쳢ꎬ쿖폐뗄퇐뺿퓲쿔뗃늻ퟣꆣ 듓쿖듺웳튵뷰죚샭싛뗄뷇뛈살뾴ꎬ웳튵뗄죚탐캪톡퓱믡펰쿬웳튵뗄춶뻶닟ꎬ웳튵춶뻶닟킧싊뮯폫럱폖믡횱뷓펰쿬죚뷰뗄엤훃킧싊ꎬ웳튵늻춬죚랽쪽톡퓱뿉쓜떼훂뗄럇킧싊춶뻶닟탐캪훷튪폐맽뛈춶ꎨoverinvestmentꎩ뫍춶늻ퟣꎨunderinvestmentꎩꆣ뻍컒맺짏쫐웳튵뛸퇔ꎬ뺡맜ꎬ뷼벸쓪컒맺짏쫐웳튵퓚막좨죚뷰뗄쪹폃랽쏦듦퓚ퟅ폃막좨죚뷰뎥뮹틸탐듻뿮ꆢ듦럅틸탐믱좡샻쾢ꆢ캯췐뷰죚믺릹춶뗈춶늻ퟣ탐캪ꎨ컄뫪ꎬ1999ꎩꎬ떫쫇ꎬ듓짏쫐웳튵뛠쓪막좨죚뷰춶뗄쪵볊쟩뿶살뾴ꎬ짏쫐웳튵막좨죚뷰뗄쪹폃룼뛠뗘뇭쿖캪웳튵샻폃막좨죚뷰춶폚룷훖킧틦늢럇샭쿫뗄탂춶쿮쒿ꎬ틔삩듳웳튵춶맦쒣ꎬ짵훁붫뷰춶죫떽튻킩웳튵풭놾늢늻쫬쾤ꆢ폫웳튵훷펪튵랶캧컞맘뗄쇬폲ꆣ듓춶뻶닟킧싊뮯뗄뷇뛈살뾴ꎬ헢샠춶탐캪뻹쫴폚맽뛈춶탐캪ꆣ춬쪱ꎬ평폚컒맺짏쫐웳튵듳뛠쫇평풭맺폐웳튵뺭맽막럝훆룄퓬뛸돉ꎬ퓚춶탐캪짏늢쎻폐췪좫냚췑풭맺폐웳튵샻폃맺폐틸탐뷰뷸탐춶삩헅뗄ꆰ춶벢뿊횢ꆱ탐캪뗄펰쿬ꎬ퓚춶뷰살풴평맺폐틸탐뷰뇤캪막좨죚뷰뫳ꎬ듳뛠쫽웳튵죔퇘쾮풭맺폐웳튵뗄춶탐캪쒣쪽ꎬ뷸탐듳맦쒣뗄맽뛈춶삩헅탐캪ꆣ틲듋ꎬ컒맺짏쫐웳튵막좨죚뷰엤훃킧싊뗍쿂뗄훷튪풭틲벰웤뇭쿖탎쪽퓚폚웳튵듦퓚웕뇩뗄맽뛈춶 2
탐캪ꆣ 컊쳢쫇막좨죚욫뫃쿂뗄컒맺짏쫐웳튵캪뫎쓜릻뷸탐웕뇩뗄맽뛈춶탐캪ꎬ컒맺짏쫐웳튵랢짺웕뇩뗄맽뛈춶탐캪뗄쓚퓚탎돉믺훆쫇쪲쎴ꆣ뛔헢튻컊쳢뗄럖컶뫍첽쳖ꎬ헽쫇놾컄뗄쒿뗄쯹퓚ꆣ 뛾ꆢ쿠맘퇐뺿벰놾컄뗄럖컶쫓뷇 뛔폚맽뛈춶뗄탎돉믺훆ꎬ쿖듺웳튵뷰죚샭싛훐뗄캯췐듺샭샭싛뫍탅쾢뺭볃톧샭싛듓늻춬뗄뷇뛈룸폨쇋럖컶뫍쮵쏷ꆣ퓚캯췐듺샭샭싛랽쏦ꎬ햲즭뫍싳뿋쇖ꎨJensen and Meckling,1976ꎩ퓚럖컶웳튵막좨죚뗄듺샭돉놾쪱횸돶ꎬ떱웳튵뗄막좨죚쪹웳튵뺭펪맜샭헟쯹돖폐뗄웳튵막좨뇈샽뇤뗃뫜킡쪱ꎬ뺭펪맜샭헟폐뿉쓜듓웤ퟔ짭뗄샻틦돶랢ꎬ퓚웳튵춶뻶닟쪱ꎬ톡퓱폐샻폚ퟔ벺뛸늢럇폐틦폚막뚫뗄춶쿮쒿삩듳뗈맽뛈춶뻶닟탐캪ꎬ떼훂웳튵맽뛈춶랢짺ꆣ햲즭(Jensenꎬ1986)룼뷸튻늽횸돶ꎬ떱웳튵듦퓚ퟅ듳솿뗄쿐폠쿖뷰쫕틦쇷솿ꎨfree cash flowꎩ쪱ꎬ웳튵뗄뺭펪맜샭헟폐뿉쓜붫웳튵뗄쿐폠쿖뷰춶폚쓜릻룸웤듸살럇뷰잮쫕틦뗄웳튵춶맦쒣삩듳뗄쿮쒿짏ꎬ듓뛸떼훂웳튵맽뛈춶탐캪뗄랢짺ꆣ퓚탅쾢뺭볃톧샭싛랽쏦ꎬ쎷튮쮹(Myers,1984)ꆢ쎷튮쮹뫍싳뷜삭럲(Myers and Majluf, 1984)죏캪ꎬ퓚웳튵췢늿춶헟뫍쓚늿뺭펪맜샭헟횮볤듦퓚ퟅ폐맘웳튵쿖폐닺볛횵믲웳튵춶쿮쒿뗄풤웚쿖뷰쇷쫕틦랽쏦뗄탅쾢늻뛔돆쪱ꎬ웳튵캪쪵쪩춶쿮쒿쯹랢탐뗄죚횤좯폐뿉쓜퓚놾쫐뎡짏놻춶헟룟맀믲뗍맀ꎬ웳튵죚횤좯뗄룟맀믲뗍맀믡떼훂웳튵춶뻶닟훐뗄맽뛈춶믲춶늻ퟣ탐캪뗄랢짺ꆣ삭쓉퇇쓏ꎨNarayananꎬ1988ꎩꆢ뫕틲뿋뛻뫍퓳웦쓉ꎨHeinkel and Zechnerꎬ1990ꎩ뗈죏캪ꎬ떱웳튵죚맽돌훐뗄탅쾢늻뛔돆뷶뷶횻쿞폚탂춶쿮쒿뗄풤웚쿖뷰쇷쫕틦쪱ꎬ폐뿉쓜믡랢짺맽뛈춶뗄탐캪ꆣ튲뻍쫇쮵ꎬ늿럖뺻쿖횵캪뢺뗄쿮쒿뿉쓜믡놻쪵쪩ꆣ풭틲퓚폚ꎬ떱탂쿮쒿쫇럱놻쪵쪩ퟷ캪캨튻뿉맛닢뗄탅뫅쪱ꎬ폃쿮쒿뗄뺻쿖횵붫웳튵췪좫쟸뇰뾪살쫇늻뿉쓜뗄ꆣ횤좯쫐뎡뻹뫢훐냼몬쇋탭뛠뻟폐늻춬뗄틔욽뻹볛횵뚨볛랢탐횤좯뗄뺻쿖횵쿮쒿ꆣ쿮쒿뺻쿖횵뗍뗄웳튵붫듓룟맀좨틦횤좯돶쫛훐믱샻ꎬ웤믱샻뿉쓜믡뎬맽뢺뺻쿖횵쿮쒿뗄쯰쪧ꆣ틲듋ꎬ듦퓚튻룶뢺뗄뺻쿖횵춶뻶닟뗣ꎨcut-off levelꎩꎬ쯹폐룟폚룃뺻쿖횵뗄쿮쒿뚼믡놻쪵쪩ꆣ 맺쓚톧헟폐맘컒맺짏쫐웳튵막좨죚욫뫃쿂맽뛈춶탎돉풭틲뗄럖컶훷튪벯훐퓚솽룶랽쏦ꆣ컄뫪ꎨ1999ꎩꆢ헔쫘맺뫍췵퇗퇗ꎨ1999ꎩ뗈믹폚캯췐듺샭샭싛뗄럖컶뿲볜ꎬ춨맽뛔컒맺짏쫐웳튵막좨죚훐뗄캯췐듺샭맘쾵뗄럖컶ꎬ죏캪퓚컒맺짏쫐웳튵쿖폐훎샭뷡릹뮷뺳쿂ꎬ좱랦폐킧볠뚽뫍풼쫸뗄웳튵뺭펪맜샭헟ힷ쟳ퟔ짭샻틦ퟮ듳뮯뫍돉놾ퟮ킡뮯ꎬ쫇떼훂컒맺짏쫐웳튵막좨죚뷰엤훃킧싊뗍쿂뗄룹놾풭틲ꎻ풬맺솼뗈ꎨ1999ꎩ춨맽뛔짏쫐웳튵막좨죚돉놾뗄쪵횤럖컶ꎬ죏캪막좨죚돉놾뗄ꆰ죭풼쫸ꆱ쪹짏쫐웳튵뗄죚돉놾뫜뗍ꎬ틲뛸뛔춶쿮쒿움볛쪱ꎬ헛쿖싊뗄튪쟳튲뫜뗍ꎬ웳튵폐컞쿞뗄뚯솦춨맽막좨죚뷸탐듳맦쒣뗄맽뛈춶ꆣ 컒쏇죏캪ꎬ컒맺횤좯쫐뎡쫇튻룶짐뒦폚랢햹훐뗄횤좯쫐뎡ꎬ쫐뎡짏춶헟폫 3
막좨죚웳튵횮볤퓚웳튵춶쿮쒿풤웚쫕틦랽쏦뗄탅쾢늻뛔돆컊쳢풶짵폚랢듯맺볒돉쫬뗄횤좯쫐뎡ꎬ짏쫐웳튵탩놨춶쿮쒿풤웚쫕틦ꆢ룼룄쒼막쮵쏷쫩뗄쟩뿶쪱폐랢짺ꆣ퓚컒맺짏쫐웳튵막좨죚맽돌훐ꎬ췢늿훐킡춶헟폫웳튵쓚늿뺭펪맜샭헟퓚폐맘웳튵닺볛횵뫍웳튵춶쿮쒿풤웚쫕틦랽쏦뗄탅쾢늻뛔돆쫇웕뇩듦퓚뗄ꆣ틲듋ꎬ퓋폃탅쾢뺭볃톧뗄샭싛뷢쫍컒맺짏쫐웳튵맽뛈춶탐캪랢짺뗄믺훆쫇뿉쓜뗄ꆣ떫쫇ꎬ탅쾢뺭볃톧샭싛훐폐맘웳튵맽뛈춶랢짺믺훆뗄샭싛럖컶쫇붨솢퓚웳튵쯹폐막욱릫뾪랢탐ꆢퟔ평붻틗ꆢ춬막춬좨뗄막좨훆뛈믹뒡횮짏뗄ꆣ뛸컒맺짏쫐웳튵막좨훆뛈낲업뗄쿔훸쳘헷쫇맺폐막ꆢ램죋막럇ퟔ평쇷춨뫍룶죋막ퟔ평쇷춨뗄춬막늻춬좨ꆣ쿔좻ꎬ퓚헢훖쟩뿶쿂ꎬ퓋폃탅쾢뺭볃톧뗄웳튵죚샭싛럖컶컒맺짏쫐웳튵맽뛈춶탐캪뗄탎돉믺훆쪱ꎬ뇘탫돤럖뾼싇웤쳘쫢뗄막좨훆뛈낲업ꆣ 컒맺짏쫐웳튵맺폐막ꆢ램죋막뫍룶죋막춬막늻춬좨뗄쳘쫢막좨훆뛈낲업떼훂쇋솽룶쏷쿔뗄뷡맻ꎺ웤튻ꎬ햼웳튵좫늿막좨뇈샽뷏뗍뗄룶죋막뗄쇷춨ꎬ쪹뗃뛠쓪살컒맺막욱쫐뎡짏막욱뗄릩룸쿠뛔폚탨쟳뛸퇔쏷쿔맽짙ꎬ웳튵막욱뗄욽뻹쫐펯싊욫룟ꎬ막욱볛룱쏷쿔욫샫웳튵뗄막욱춶볛횵ꎻ웤뛾ꎬ늻춬막좨쯹폐헟뗄탐캪쒿뇪쏷쿔듦퓚ퟅ쏷쿔닮틬ꆣ룶죋막막뚫춶뗄훷튪쒿뗄퓚폚믱좡막욱쇷춨죃뗄놾샻뗃ꎨcapital gainꎩ쫕틦ꎬ웤탐캪쒿뇪캪웳튵막욱쫐횵뗄ퟮ듳뮯ꎻ맺폐막막뚫평폚웤막좨컞램퓚횤좯쫐뎡쇷춨죃ꎬ웤탐캪쒿뇪캪맺폐막쯹듺뇭뗄닺ꡄ맺폐닺뗄퓶횵ퟮ듳뮯ꆣ 컒쏇랢쿖ꎬ벴쪹늻뾼싇탅쾢늻뛔돆틲쯘ꎬ컒맺짏쫐웳튵쿖폐막좨훆뛈낲업쿂뗄웳튵막욱볛룱맽룟욫샫웳튵닺볛횵ꆢ늻춬막뚫뗄쒿뇪닮틬뗈튲믡떼훂웳튵막좨죚쿂맽뛈춶탐캪뗄랢짺ꎻ퓚춬쪱뾼싇탅쾢늻뛔돆뫍컒맺짏쫐웳튵쳘쫢막좨훆뛈낲업뗄쟩뿶쿂ꎬ폫뷶뾼싇탅쾢늻뛔돆틲쯘뗄춬막춬좨웳튵막좨죚쿂뗄춶탐캪쿠뇈ꎬ컒맺짏쫐웳튵막좨죚쿂맽뛈춶랢짺뗄뿉쓜탔튪듳뗃뛠ꆣ웤뷡맻쫇컒맺웳튵막좨죚욫뫃쿂뗄맽뛈춶탐캪뗄랢짺믡룼캪웕뇩뫍뿉쓜ꆣ 틲듋ꎬ놾컄듓탅쾢늻뛔돆뗄뷇뛈돶랢ꎬ뷡뫏컒맺짏쫐웳튵쿖폐뗄막좨훆뛈낲업ꎬ퓋폃튻룶냼몬폐탅쾢늻뛔돆뫍쿖폐막좨훆뛈낲업쿂뗄막뚫쒿뇪닮틬뗈틲쯘퓚쓚뗄웳튵막좨죚춶뻶닟쒣탍ꎬ럖컶컒맺짏쫐웳튵막좨죚욫뫃쿂맽뛈춶탐캪웕뇩랢짺뗄탎돉믺훆ꎬ틔쮵쏷컒맺짏쫐웳튵막좨죚뷰엤훃킧싊뗍쿂뗄돉틲ꆣ 놾컄틔쿂뗄뷡릹낲업캪ꎺ뗚죽뷚붨솢튻룶탅쾢늻뛔돆쿂뗄웳튵막좨죚쒣탍ꎬ럖컶탅쾢늻뛔돆쟩뿶쿂ꎬ웳튵춶뻶닟훐맽뛈춶랢짺뗄뿉쓜탔컊쳢ꎻ뗚쯄뷚럖컶컒맺짏쫐웳튵쿖폐막좨훆뛈낲업쿂ꎨ늻뾼싇탅쾢늻뛔돆틲쯘ꎩꎬ웳튵막좨죚춶뻶닟뫍맽뛈춶랢짺뗄뿉쓜탔컊쳢ꎻ뗚컥뷚쫇탅쾢늻뛔돆뫍쿖폐막좨훆뛈낲업쿂웳튵막좨죚춶뻶닟뫍맽뛈춶랢짺뗄뿉쓜탔럖컶ꎻ뗚쇹뷚쫇놾컄럖컶뗄뷡싛ꆣ 죽ꆢ 탅쾢늻뛔돆쿂뗄웳튵막좨죚폫맽뛈춶 1ꎮ탅쾢늻뛔돆쿂웳튵막좨죚뗄믹놾쒣탍 4
볙짨횤좯쫐뎡짏폐N룶짏쫐웳튵ꎬ쎿튻룶웳튵뚼펵폐튻룶춶뛮캪I뗄춶쿮쒿ꆣ쯹폐웳튵뻹춨맽퓶랢탂막뗄랽쪽돯벯춶쿮쒿뗄뷰ꆣ퓶랢탂막뫳ꎬ탂막막뚫쯹돖막럝햼웳튵ퟜ막놾뗄뇈샽캪aꆣi웳튵쿖폐닺뗄막욱쫐뎡볛횵캪Si(iꎽ1,2,ꆭ,N)ꎬSi캪횤좯쫐뎡뺭볃훷쳥횮볤뗄릲춬횪쪶ꆣi웳튵춶쿮쒿뗄풤웚쫕틦뺻쿖횵캪Viꎨiꎽ1,2,ꆭ,Nꎩꆣ 웳튵뗄쓚늿뺭펪맜샭헟펵폐웳튵춶쿮쒿쪵쪩폫럱뗄뻶닟좨ꎬ떫쫇ꎬ웳튵뺭펪맜샭헟뗄샻틦쒿뇪폫쿖폐막뚫(샏막뚫)뗄샻틦쒿뇪튻훂ꆣ쿖폐막뚫뗄쒿뇪캪웳튵막욱쫐뎡볛횵뗄ퟮ듳뮯ꆣ 퓚웳튵춶쿮쒿뗄풤웚쫕틦뺻쿖횵랽쏦ꎬ췢늿춶헟폫웳튵뗄쓚늿뺭펪맜샭헟횮볤듦퓚ퟅ탅쾢늻뛔돆ꆣ웳튵뗄쓚늿뺭펪맜샭헟좷쟐뗘횪뗀웤춶쿮쒿뗄풤웚쫕틦뺻쿖횵ꎻ췢늿춶헟횪뗀웳튵쿖폐닺뗄막욱쫐뎡볛횵ꎬ뛸뛔쎿튻웳튵춶쿮쒿뗄풤웚쫕틦뺻쿖횵좴늻쟥돾ꎬ횻펵폐튻룶맘폚쎿튻웳튵춶쿮쒿풤웚쫕틦뺻쿖횵럖늼뗄훷맛룅싊ꆣPi캪췢늿춶헟뛔i웳튵춶쿮쒿풤웚쫕틦뺻쿖횵뗄훷맛룅싊ꆣ퓚헢훖쟩뿶쿂ꎬ췢늿춶헟뛔쯹폐웳튵춶쿮쒿뗄풤웚쫕틦뺻쿖횵내웤펵폐뗄훷맛룅싊럖늼뷸탐에뛏ꎬ벴췢늿춶헟에뛏뗄쯹폐웳튵춶쿮쒿뗄욽뻹풤웚쫕틦뺻쿖횵V캪 VꎽN∑PV (1) iiiꎽꎱ 듋쪱ꎬ퓚횤좯쫐뎡짏ꎬ쯹폐뗄웳튵뚼뿉틔룹뻝췢늿춶헟움볛뗄웳튵춶쿮쒿뗄풤웚쫕틦뺻쿖횵V살좷뚨웤막욱랢탐볛룱ꎬ랢탐막욱ꎬ돯벯춶쿮쒿뷰ꆣ 2ꎮ탅쾢늻뛔돆쿂막좨죚웳튵뗄춶뻶닟폫맽뛈춶 퓚짏쫶쒣탍볙뚨쿂ꎬ듓쿖폐막뚫샻틦돶랢뗄웳튵뺭펪맜샭헟쪵쪩춶쿮쒿뗄쳵볾캪 (1ꎭa)(SiꎫViꎫI)ꎾSi (2) 헢샯ꎬaꎽIꆡꎬaꎾ0ꎬ벴탂막막뚫퓚춶쿮쒿쪵쪩뫳웳튵닺ퟜ횵훐뗄S+I+Vi럖엤뇈싊ꆣ(2)쪽캪쿖폐막뚫쪵쪩춶쿮쒿쯹믱뗃뗄뺻쫕틦캪헽뗄쳵볾ꆣ뛔(2)쪽뷸탐뇤뮻헻샭ꎬ뿉뗃떽죧쿂뺭펪맜샭헟쪵쪩춶쿮쒿뗄쳵볾 ViꎾꎭaꎱꎭVꆡꆡ (3) a 컒쏇돆(3)쪽뗄폒뇟캪웳튵춶뻶닟뗄뻶닟뗣ꎨcut-off levelꎩꆣ 퓚(3)쪽훐ꎬ틑횪aꎾ0ꎬ횻튪Vꎾ0ꎬ웳튵뗄춶뻶닟뗣ꎭaꎱVꆡꎼ0ꎬ듋쪱ꎬ쿂−a쇐늻뗈쪽췪좫폐뿉쓜돉솢 a 0ꎾViꎾꎭꎱꎭVꆡꆡ (4) a 5
a(4)쪽뇭쏷ꎬ떱i웳튵춶쿮쒿뗄풤웚쫕틦뺻쿖횵Viꇊ(ꎭVꆡ,ꆡ0)쪱ꎬ웳튵뗄1−a뺭펪맜샭헟믡쪵쪩춶쿮쒿ꎬ맽뛈춶뗄쿖쿳랢짺ꆣ 쯄ꆢ컒맺막좨훆뛈낲업쿂뗄웳튵막좨죚폫맽뛈춶 1ꎮ컒맺짏쫐웳튵막좨훆뛈낲업벰웤펰쿬?컒맺짏쫐웳튵막좨훆뛈낲업뗄쳘뗣쫇막좨뷡릹뗄죋캪럖룮ꎬ쟒춬막늻춬좨ꆣ평폚컒맺랢햹횤좯쫐뎡뗄돵훔쫇췆뚯맺폐웳튵룄룯ꎬ짏쫐웳튵훷튪쫇평맺폐웳튵룄훆뛸돉ꎬ쯹틔ꎬ붫짏쫐릫쮾뗄막좨내웤돖폐헟뗄늻춬럖캪맺볒막ꆢ램죋막뫍룶죋막ꆣ늢쟒ꎬ캪쇋좷놣맺폐막뗄뿘막뗘캻ꎬ맦뚨맺폐막뫍램죋막늻쓜ퟔ평쇷춨ꎬ쫐뎡짏횻폐ㄯ?ퟳ폒뗄룶죋막뿉틔ퟔ평쇷춨ꎨ볻뇭?ꎩꆣ??뇭ㄠ짏붻쯹뫍짮붻쯹쫐뎡쇷춨맦쒣뫍막좨뷡릹?†††††††††††?ꎨ뷘횹㈰〱쓪㜠퓂㌱죕ꎩ†††?떥캻ꎺ틚풪ꎨ막ꎩ?††?막욱쫐횵†쇷춨쫐횵†뇈샽⠥⤠ퟜ막놾†쇷춨막놾†뇈샽⠥⤠†떱퓂욽뻹쫐펯싊?짏몣†ㄹ㠲㌠††㜱㘲†††㌷⸸㔠†ㄶ㐶††‶㌰†††″㠮㈷†††‴㘮㤹?짮?†㈷㔱㠠††㤱〹†††㌳⸱††㈳〲††‷㘵†††″㌮㈳†††‴㤮〲?뫏볆†㐶㐴ㄠ†‱㘲㜱†††㌵⸰㌠†㌸㐸††ㄳ㤵†††″㔮㌳†††??†힢ꎺㄮ짏쫶쫽뻝냼삨?막뫍?막ꎻ?㈮욽뻹쫐펯싊쫇틔랢탐ퟜ막놾볆쯣뗄ꆣ?쇏살풴ꎺꆶ횤좯쫐뎡떼놨?ꆷ㈰〱쓪?퓂뫅ꎬ짮?횤좯붻틗쯹ꆣ??컒맺짏쫐웳튵뗄헢훖막좨훆뛈낲업뛔횤좯쫐뎡뗄막욱볛룱ꆢ웳튵막뚫탐캪쒿뇪틔벰웳튵뗄쓚늿뺭펪맜샭뗈랽쏦뻹닺짺쇋짮뿌뗄펰쿬ꆣ?퓚횤좯쫐뎡막욱볛룱랽쏦ꎬ평폚햼짏쫐웳튵막좨뻸듳늿럖뇈샽뗄맺폐막뫍램죋막늻쓜ퟔ평쇷춨ꎬ쫐뎡짏횻폐짙솿뗄룶죋막쇷춨ꎬ퓚컒맺막욱쫐뎡돉솢뗄돵웚ꎬ쫐뎡뗄릩룸맦쒣뻍놻죋캪쯵킡ꎬ떼훂쫐뎡막욱볛룱늻뛏짏헇ꎬ펪퓬쇋튻룶막쫐ꆰ잮ꆱ뗄쫐뎡킧펦ꎬ컼틽짧믡뷰풴풴늻뛏뗘쇷죫막욱쫐뎡ꆣ막욱쫐뎡뗄릩쟳늻욽뫢쪹웳튵막욱뗄욽뻹쫐펯싊욫룟ꎬ막욱볛룱쏷쿔룟폚웤춶볛횵ꆣ?쇭튻랽쏦ꎬ늻춬샠뇰막좨뗄쇷춨탔늻춬ꎬ떼훂쇋막뚫춶탐캪쒿뇪뗄럖뮯ꎬ늻춬막뚫쯹ힷ쟳뗄샻틦쒿뇪돊쿖돶쏷쿔닮틬ꆣ평폚룶죋막막좨뗄뿉쇷춨탔ꆢ막쫐랢햹돵웚막욱쫐뎡뗄ꆰ잮ꆱ킧펦ꆢ룶죋막막좨뇈샽맽킡틔벰룶죋막막뚫놾짭뛔웳튵뺭펪맜샭볠뚽랽쏦뗄ꆰ듮뇣뎵ꆱ탐캪뗈랽쏦뗄풭틲ꎬ컒맺횤좯쫐뎡짏ꎬ룶죋막막뚫춶뗄쒿뇪쏷쿔뗘뇭쿖캪ힷ쟳웳튵막욱쫐뎡볛룱뗄ퟮ듳뮯ꎬ틔웚춨맽퓚쫐뎡짏죃막좨ꎬퟮ듳쿞뛈뗘믱뗃막욱춶뗄놾샻뗃쫕틦ꎻ맺폐막뫍램죋막늻쓜퓚쫐뎡짏ퟔ평쇷춨ꎬ웤막욱뗄쫐뎡볛횵뛔웤막뚫쎻폐쪵볊틢틥ꆣ폖틲캪컒맺막쫐뗄춶믺탔뷏잿ꎬ막욱쫐볛늻쓜헦쪵랴펳웳튵닺뗄볛횵ꎬ틲듋늻쓜ퟷ캪움볛맺폐 6
닺뺭펪뗄뾼뫋횸뇪ꆣ퓙헟ꎬ듓컒맺막럝훆룄룯뗄돵훔살뾴ꎬ맺폐막뫍램죋막막뚫뗄훷튪쒿뗄쫇쾣췻춨맽막럝훆룄룯쪵쿖맺폐닺틔벰웳튵램죋닺뗄놣횵뫍퓶횵ꆣ퓚막럝훆웳튵훐ꎬ맺폐닺놣횵퓶횵훷튪뇭쿖캪웳튵뺻닺뫍뺻닺쫕틦뗄퓶볓ꆣ뛸쟒ꎬ뷼벸쓪퓚횤좯쫐뎡짏쯹랢짺뗄맺폐막뫍램죋막뗄킭틩죃ꎬ웤킭틩죃볛룱튲쫇틔뺻닺캪믹뒡훆뚨뗄ꆣ틲듋ꎬ맺폐막뫍램죋막막뚫ힷ쟳뗄쒿뇪쫇웳튵뺻닺볛횵뗄ퟮ듳뮯ꆣ?샭싛짏ꎬ짏쫐웳튵뺭펪맜샭헟뗄뺭펪쒿뇪펦럾듓좫쳥막뚫샻틦뗄ퟮ듳뮯ꆣ떫쫇ꎬ퓚웳튵룷샠막뚫쯹ힷ쟳뗄쒿뇪늻튻훂뗄쟩뿶쿂ꎬ웳튵뺭펪쒿뇪뗄좷뚨좡뻶폚룷샠막뚫뛔짏쫐웳튵쪣폠뿘훆좨뗄쪵쿖ꆣ튻냣뛸퇔ꎬ퓚막럝훆웳튵훐ꎬ막뚫훷튪춨맽솽훖춾뺶살쪵쪩뛔웳튵뗄뿘훆좨ꎺ튻쫇쓚늿뿘훆ꎨ楮瑥牮慬潮瑲潬ꎩꎻ뛾쫇램죋뿘훆쫐뎡ꎨ浡牫整潲潲灯牡瑥潮瑲潬ꎩꆣ쓚늿뿘훆쫇막뚫틔웤돖폐막욱뗄춶욱좨ꎬ춨맽춶욱톡뻙릫쮾뚭쫂믡ꎬ평뚭쫂믡톡퓱웳튵뗄뺭펪맜샭헟ꎬ붫웳튵죕뎣뺭펪뗄뻶뚨맜샭좨캯췐룸뺭펪맜샭헟살쪵쿖뗄ꆣ쓚늿뿘훆뗄폐킧탔좡뻶폚죽룶랽쏦뗄틲쯘ꎺꋙ웳튵막럝쯹폐뗄벯훐돌뛈ꎻꋚ막뚫뗄탔훊ꎬ벴막뚫쫇럱펵폐뷏잿뗄볠뚽쓜솦ꎻꋛ막뚫춶욱좨쿞뗄잿죵ꆣ램죋뿘훆쫐뎡쫇춨맽막좨뗄ퟔ평쇷뚯살쪵쿖짏쫐릫쮾뿘막좨뗄틆ꆢ릫쮾볤뗄볦늢뫍쫕릺ꎬ틔듯떽웳튵킧싊뺭펪뗄쒿뗄ꆣ램죋뿘훆쫐뎡폐킧퓋ퟷ뗄잰쳡쫇ꎺꋙ웳튵쯹폐막욱릫뾪랢탐ꎬ쟒막좨돖폐헟럖즢ꎻꋚ웳튵쯹폐막욱뻹뿉퓚쫐뎡짏ퟔ평쇷춨ꎨ엋쏴ꎬ㈰〱ꎩꆣ?퓚컒맺횤좯쫐뎡짏ꎬ평폚맺폐막뫍램죋막늢럇릫뾪랢탐ꎬ튲늻쓜퓚쫐뎡짏ퟔ평쇷춨ꎬ늢쟒막볛늻랴펳릫쮾뗄춶볛횵ꎬ틲뛸좱랦막뚫췢늿뿘훆뗄램죋뿘훆쫐뎡폐킧퓋ퟷ뗄믹뒡ꆣ뛸퓚막뚫뗄쓚늿뿘훆랽쏦ꎬ뺡맜짏쫐웳튵뗄쓚늿훎샭랽쏦죔듦퓚튻뚨뗄좱쿝ꎬ떫쫇ꎬ컒맺짏쫐웳튵뛠쫽평맺볒믲헟맺폐춶떥캻뿘막ꎬ맺폐막뫍램죋막막뚫뗄돖막뇈샽듳듳뎬맽룶죋막막뚫뗄돖막뇈샽ꎬ막좨벯훐뛈뫜룟ꎬ맺폐막막뚫믹놾짏ퟳ폒ퟅ짏쫐릫쮾맜샭닣뗄죎쏼뫍훘듳춶뻶닟ꆣ뛸쟒ꎬ뛔짏쫐웳튵뗄돩퇹뗷닩튲뇭쏷ꎺ컒맺짏쫐릫쮾뗄훐룟닣맜샭죋풱믹놾짏살풴폚놻룄퓬뗄맺폐웳튵ꎬ쟒폐㘵?뗄뚭쫂뎤볦죎ퟜ뺭샭ꎨ쳯횾쇺뗈ꎬㄹ㤸ꎩꆣ퓚헢훖쟩뿶쿂ꎬ컒맺짏쫐웳튵쓚늿뺭펪헟뗄뺭펪쒿뇪쳥쿖뗄펦쫇ퟷ캪뿘막막뚫뗄맺폐막막뚫뗄샻틦쒿뇪ꎬ벴쪵쿖웳튵뺻닺볛횵뗄ퟮ듳뮯ꆣ????막뚫쒿뇪닮틬쿂뗄웳튵막좨죚폫춶뻶닟?룹뻝짏쏦뗄럖컶ꎬ컒쏇뿉틔붨솢튻룶컒맺짏쫐웳튵막좨훆뛈낲업쿂뗄웳튵막욱죚뫍춶뻶닟쒣탍ꆣ컒쏇볌탸퇘폃뗚죽뷚탅쾢늻뛔돆쒣탍훐뗄믹놾볙짨ꆣ쯹늻춬뗄쫇ꎬ퓚헢샯ꎬ컒쏇퓝늻뾼싇췢늿춶헟폫웳튵쓚늿뺭펪맜샭헟횮볤퓚웳튵춶쿮쒿풤웚쫕틦뺻쿖횵랽쏦뗄탅쾢늻뛔돆컊쳢ꎬ벴웳튵춶쿮쒿뗄풤웚쫕틦뺻쿖횵?i쫇쫐뎡뗄릲춬횪쪶ꆣ춬쪱뫏샭뗘늹돤틔쿂볙짨ꎺ?ꋙ짏쫐웳튵뗄막뚫평튻룶돖폐햼웳튵뛠쫽막좨뇈샽뗄맺폐막믲램죋막뗄뿘막막뚫틔벰훚뛠뗄돖폐룶죋막막좨뗄훐킡막뚫릹돉ꆣ맺폐막뫍램죋막늻쓜ퟔ평쇷춨죃ꎬ웤돖폐헟뗄탐캪쒿뇪캪ힷ쟳웳튵뺻닺볛횵뗄ퟮ듳뮯ꎻ룶죋막뿉틔ퟔ평쇷 7
춨죃ꎬ웤돖폐헟뗄탐캪쒿뇪캪웳튵막욱쫐뎡볛횵뗄ퟮ듳뮯ꆣ?ꋚ횤좯쫐뎡짏ꎬ웳튵막욱뗄쫐펯싊웕뇩욫룟ꎬ룷웳튵막욱뗄쫐뎡볛횵쏷쿔룟폚웤뺻닺볛횵ꆣ?ꋛ뺡맜컒맺짏쫐웳튵막좨죚뗄랽쪽횮튻쫇엤막죚ꎬ떫쫇ꎬ평폚퓚엤막맽돌훐ꎬ뷏뛠웳튵뗄맺폐막막뚫뫍램죋막막뚫럅웺엤막믲틔쪵컯닺뗄탎쪽엤막ꎬ벸뫵쎻폐맺폐막막뚫믲램죋막막뚫틔쪵볊춶죫뷰뗄랽쪽엤막ꎬ컒맺짏쫐웳튵뗄헢훖엤막죚랽쪽쪵볊짏죔쫴폚퓶랢탂막죚ꆣ쯹틔ꎬ컒쏇볙뚨ꎬ짏쫐웳튵뗄막좨죚랽쪽뻹캪퓶랢탂막ꎬ퓶랢뗄탂막뻹캪뿉쇷춨뗄룶죋막ꆣ?ꋜ웳튵쓚늿뺭펪맜샭헟뗄탐캪쒿뇪폫맺폐막막뚫뗄탐캪쒿뇪튻훂ꎬ벴ힷ쟳웳튵뺻닺볛횵뗄ퟮ듳뮯ꆣ?ꋝ횤좯횵쫐뎡짏ꎬi웳튵쿖폐뺻닺뗄ퟜ볛횵캪Ciꆣ 퓚짏쫶믹놾볙뚨쿂ꎬ컒쏇뿉틔뗃떽i웳튵춨맽막좨죚쪵쪩춶쿮쒿뗄쳵볾캪 (1ꎭg)(Ci +Vi +I)ꎾCi (5) 듋쪱Ⱐ탂막막뚫퓚춶쿮쒿쪵쪩뫳웳튵닺ퟜ횵훐뗄럖엤뇈싊캪?IIC+V+Ig==×iiꎻ S+V+IC+V+IS+V+IiiiiiiC+V+Iii 쇮ꛂ= S+V+Iii퓲bIg= ††††††††††††† (6)?C+V+Iii?컒쏇돆b캪춬막늻춬좨쿂뗄막뚫쒿뇪닮틬쾵쫽ꎬ웤럖ퟓ캪맺폐막막뚫뗄탐캪쒿뇪뇭쫶쪽ꎬ럖쒸캪룶죋막막뚫뗄탐캪쒿뇪뇭쫶쪽ꆣb뗄뇭쫶쪽뇭쏷ꎬi웳튵막욱쫐뎡볛횵Si룟폚웤쿖폐뺻닺볛횵Ci뗄럹뛈풽듳ꎬ맺폐막막뚫뫍룶죋막막뚫횮볤뗄쒿뇪닮틬풽듳ꎬ막뚫쒿뇪닮틬쾵쫽풽킡ꎬ(6)쪽쯹뇭쪾뗄탂막막뚫퓚춶쿮쒿쪵쪩뫳웳튵ퟜ닺볛횵훐뗄럖엤뇈샽튲풽킡ꆣ퓚헢훖쟩뿶쿂ꎬ탂막막뚫막욱춶뗄쒿뗄튲뻍풽쟣쿲폚춨맽횤좯쫐뎡뗄막좨죃믱좡막욱춶뗄놾샻뗃쫕틦ꆣ 붫(6)쪽듺죫(5)쪽늢뷸탐쫊떱헻샭ꎬ컒쏇뿉틔뷸튻늽뗃떽i웳튵쪵쪩춶쿮쒿뗄쳵볾캪ꎺ Viꎾ−(1−b)I (7) (7)쪽뗄폒뇟캪i웳튵퓚쿖폐막좨훆뛈낲업쿂ꎬ샻폃막좨죚쪵쪩춶쿮쒿뗄뻶닟뗣ꆣ 틲캪컒맺짏쫐웳튵뗄막욱쫐뎡볛횵튻냣룟폚웤쯹듺뇭뗄웳튵뺻닺볛횵ꎬ벴Ci ꎼSiꎬ쯹틔ꎬ 0ꎼbꎼ1ꎬ듋쪱ꎬ−(1−b)Iꎼ0ꆣ 떱i웳튵춶쿮쒿뗄풤웚쫕틦뺻쿖횵Vi∈(−(1−b)Iꎬ0)쪱ꎬ쓚늿뺭펪맜샭헟튲믡쪵쪩춶쿮쒿ꎬ맽뛈춶뗄쿖쿳랢짺ꆣ뛸쟒ꎬ죧맻웳튵막욱뗄쫐뎡볛횵룟폚웤뺻닺볛횵뗄럹뛈풽듳ꎬb뻍믡풽킡ꎬ−(1−b)I튲믡풽킡ꎬ웳튵랢짺맽뛈춶탐캪뗄뿉쓜탔믡뇤뗃풽듳ꆣ 8
컥ꆢ탅쾢늻뛔돆뫍컒맺막좨훆뛈낲업쿂뗄웳튵막좨죚폫맽뛈춶 퓚뗚쯄뷚훐ꎬ컒쏇쎻폐뾼싇탅쾢늻뛔돆뗄틲쯘ꎬ웤쒿뗄퓚폚쮵쏷ꎬ벴쪹쫇늻듦퓚탅쾢늻뛔돆틲쯘ꎬ컒맺짏쫐웳튵쿖폐뗄막좨훆뛈낲업튲폐뿉쓜떼훂웳튵랢짺막좨죚쿂뗄맽뛈춶탐캪ꆣ퓚놾뷚ꎬ컒쏇춬쪱뾼싇탅쾢늻뛔돆뫍컒맺쳘쫢뗄막좨훆뛈낲업솽랽쏦뗄틲쯘ꎬ럖컶퓚헢솽랽쏦틲쯘춬쪱듦퓚뗄쟩뿶쿂ꎬ웳튵막좨죚쿂뗄춶뻶닟뫍맽뛈춶탐캪랢짺뗄뿉쓜탔ꆣ 1ꎮ탅쾢늻뛔돆뫍컒맺쳘쫢막좨훆뛈낲업쿂뗄웳튵춶뻶닟 컒쏇횻탨튪퓚뗚쯄뷚뗄볙뚨훐틽죫탅쾢늻뛔돆틲쯘ꎬ뻍뿉틔럖컶탅쾢늻뛔돆뫍컒맺막좨훆뛈낲업쿂ꎬ웳튵샻폃막좨죚쪵쪩춶쿮쒿뗄춶뻶닟ꆣ 틲듋ꎬ컒쏇볙뚨ꎬ짏쫐웳튵퓚퓶랢탂막죚쪱ꎬ췢늿춶헟뫍웳튵쓚늿뺭펪맜샭헟횮볤퓚폐맘웳튵춶쿮쒿풤웚쫕틦뺻쿖횵랽쏦듦퓚ퟅ탅쾢늻뛔돆ꆣ퓚헢훖쟩뿶쿂ꎬ췢늿춶헟뛔쯹폐웳튵춶쿮쒿풤웚쫕틦뺻쿖횵뗄움볛횵캪(1)쪽쯹뇭쪾뗄Vꆣ룷짏쫐웳튵퓚췢늿춶헟뛔쯹폐죚웳튵춶쿮쒿뗄풤웚쫕틦뺻쿖횵뗄움볛횵캪V뗄쳵볾쿂ꎬ뻶뚨웳튵막욱랢탐볛룱ꎬ랢탐탂막죚ꆣ 듋쪱ꎬi짏쫐웳튵뗄뺭펪맜샭헟샻폃탂막죚쪵쪩춶쿮쒿뗄쳵볾캪 (1ꎭq)(CiꎫVi ꎫI)ꎾCi (8) 퓚틽죫탅쾢늻뛔돆뗄쳵볾쿂ꎬ탂막막뚫퓚춶쿮쒿쪵쪩뫳웳튵ퟜ닺볛횵훐뗄럖엤뇈싊캪 †?Iq=ꎽa (9) S+V+Ii컒쏇뚨틥C+V+Il=i캪냼몬탅쾢늻뛔돆틲쯘뗄쿖폐막좨훆뛈낲업쿂뗄막뚫쒿S+V+Ii뇪닮틬쾵쫽ꆣ뛔(9)쪽뷸탐쫊떱뇤뮻헻샭ꎬ뿉틔뗃떽 IC+V+IlIqꎽ×i= (10) C+V+IS+V+IC+V+Iiii붫(10)쪽듺죫(8)쪽늢뷸탐쫊떱헻샭ꎬ뿉틔뷸튻늽뗃떽i짏쫐웳튵쓚늿뺭펪맜샭헟쪵쪩춶쿮쒿뗄쳵볾캪 q1−l V>−V−I (11) i1−q1−q(11)쪽폒뇟캪탅쾢늻뛔돆뫍쿖폐막좨훆뛈낲업쿂ꎬi짏쫐웳튵샻폃막좨죚쪵쪩춶쿮쒿뗄춶뻶닟뗣ꆣ 평폚ꎬ0ꎼqꎼ1ꆢ0ꎼlꎼ1ꆢIꎾ0 쯹틔ꎬi웳튵뗄춶뻶닟뗣q1−l−V−Iꎼ0ꆣ 1−q1−q떱i웳튵춶쿮쒿뗄풤웚쫕틦뺻쿖횵Viꇊq1−l(−V−Iꎬ0)쪱ꎬ웳튵뗄쓚1−q1−q 9
늿뺭펪맜샭헟믡쪵쪩춶쿮쒿ꎬ맽뛈춶탐캪랢짺ꆣ 2ꎮ탅쾢늻뛔돆폫컒맺쳘쫢막좨훆뛈낲업쿂맽뛈춶랢짺뿉쓜탔럖컶 퓚탅쾢늻뛔돆뫍컒맺짏쫐웳튵쿖폐쳘쫢막좨훆뛈낲업쿂ꎬ짏쫐웳튵춶쿮쒿풤웚쫕틦뺻쿖횵뗄좡횵쟸볤q1−l(−V−I,0) 캪웤맽뛈춶뿉쓜랢짺뗄랶캧ꆣ1−q1−q뗚죽뷚뗄럖컶뇭쏷ꎬ돉쫬횤좯쫐뎡짏ꎬ탅쾢늻뛔돆쿂뗄춬막춬좨웳튵샻폃막좨죚쪵쪩춶쿮쒿쪱ꎬ맽뛈춶뿉쓜랢짺랶캧캪춶쿮쒿풤웚쫕틦뺻쿖횵퓚(ꎭaVꎬ0)쟸볤쓚ꆣ룹뻝(9)쪽ꎬaꎽqꎬ붫웤듺죫(11)ꎬ뿉틔뗃떽죧쿂뷡싛ꎺ퓚춬1−a캪탅쾢늻뛔돆쳵볾쿂ꎬ폫춬막춬좨ꆢ막좨럖즢뗄막럝훆웳튵쿠뇈ꎬ쿖폐막좨훆뛈낲업쿂뗄컒맺짏쫐웳튵샻폃막좨죚쪵쪩춶쿮쒿쪱랢짺맽뛈춶뿉쓜탔뗄랶캧삩듳쇋1−lIꎨ뻸뛔횵ꎩ늿럖ꆣ룃뷡싛뇭쏷ꎬ퓚컒맺짏쫐웳튵쿖폐뗄막좨훆뛈낲업1−a쿂ꎬ짏쫐웳튵춶쿮쒿뗄풤웚쫕틦뺻쿖횵벴쪹럇뎣닮ꎬ웳튵뗄뺭펪맜샭헟튲쓜릻샻폃막좨죚살쪵쪩룃춶쿮쒿ꆣ 틔쿂ꎬ컒쏇뷸튻늽럖컶탂막막뚫퓚춶쿮쒿쪵쪩뫳웳튵ퟜ닺볛횵훐뗄럖엤뇈싊q뫍막뚫쒿뇪닮틬쾵쫽l뇤뮯뛔웳튵맽뛈춶랢짺뿉쓜탔뗄펰쿬ꆣ 캪뇣폚럖컶ꎬ컒쏇폃웳튵춶쿮쒿풤웚쫕틦뺻쿖횵좡횵쟸볤뗄뻸뛔횵 q1−lq1−lf(q,l)=0−−−=V+I (12) 1−q1−q1−q1−q살뛈솿짏쫐웳튵맽뛈춶랢짺뿉쓜탔랶캧뗄듳킡ꆣ춬쪱ꎬ볙뚨퓚헢튻쟸볤쓚ꎬ웳튵랢짺맽뛈춶탐캪뗄룅싊럖늼캪뻹퓈럖늼ꆣ 퓚V뫍I 튻뚨뗄쟩뿶쿂ꎬf(q,l)평q뫍l솽룶뇤솿뻶뚨ꆣ붫f(q,l)뛔q쟳떼ꎬ뿉뗃 ∂f∂fdlC' (q,l)=+×=−ifq<0 (13) ∂q∂ldq(1−q2) (13)쪽뇭쏷ꎺ퓚췢늿춶헟뛔웳튵춶쿮쒿풤웚뺻쿖횵쫕틦움볛횵V뫍쒼벯뷰I튻뚨뗄쟩뿶쿂ꎬ탂막막뚫퓚웳튵ퟜ닺볛횵훐뗄럖엤뇈싊폫웳튵맽뛈춶뗄뿉쓜탔돉랴뇈ꎬ벴탂막막뚫퓚쿮쒿춶뫳웳튵닺볛횵훐뗄럖엤뇈싊풽뗍ꎬ맽뛈춶랢짺뗄뿉쓜탔풽듳ꆣ 춬퇹뗘ꎬ붫f(q,l)뛔l쟳떼ꎬ뿉뗃 ∂f∂fdqqC' fl(q,l)=+×=−i<0 (14) ∂l∂qdl(1−q2)l(14)쪽뇭쏷ꎺ퓚V뫍I튻뚨뗄쟩뿶쿂ꎬ막뚫쒿뇪닮틬쾵쫽l폫맽뛈춶뗄뿉쓜탔돉랴뇈ꎬ벴웳튵막욱쫐뎡볛횵룟폚웳튵뺻닺볛횵뗄럹뛈풽듳ꎬl풽킡ꎬ맽뛈춶랢짺뗄뿉쓜탔풽듳ꎬ막욱뗄볛룱맽룟뛔짏쫐릫쮾막좨죚뫍맽뛈춶뻹폐듌벤ퟷ폃ꆣ 10
뺡맜ꎬ탂막막뚫퓚쿮쒿춶뫳웳튵닺볛횵훐뗄럖엤뇈싊뇤뮯뫍막뚫쒿뇪닮틬쾵쫽뇤뮯뛔웳튵맽뛈춶랢짺뿉쓜탔뗄펰쿬랽쿲쫇튻훂뗄ꎬ떫쫇ꎬ떼훂솽헟뛔웳튵맽뛈춶랢짺뿉쓜탔펰쿬뗄풭틲쫇늻튻퇹뗄ꆣ탂막막뚫퓚쿮쒿춶뫳웳튵닺볛횵훐뗄럖엤뇈싊뇤뮯뛔웳튵맽뛈춶랢짺뿉쓜탔뗄펰쿬풴폚웳튵막좨죚맽돌훐췢늿춶헟폫쓚늿뺭펪맜샭헟퓚웳튵춶쿮쒿풤웚쫕틦랽쏦뗄탅쾢늻뛔돆ꆣ퓚췢늿춶헟폫웳튵쓚늿뺭펪맜샭헟횮볤듦퓚ퟅ탅쾢늻뛔돆뗄쟩뿶쿂ꎬ탂막막뚫퓚쿮쒿춶뫳웳튵닺볛횵훐뗄럖엤뇈싊뗄붵뗍ꎬ틢캶ퟅ쿠뛔폚췢늿춶헟뛔쯹폐웳튵춶쿮쒿풤웚쫕틦뺻쿖횵뗄움볛횵뛸퇔ꎬ늿럖짏쫐웳튵춶쿮쒿뗄풤웚쫕틦뺻쿖횵뫍막욱쫐뎡볛룱놻듳럹뛈뗘룟맀ꎬ웳튵샻폃막좨죚믱뗃뗄뛮췢막욱틧볛쫕틦퓶볓ꆣ듋쪱ꎬ웳튵쪵쪩풤웚쫕틦뺻쿖횵캪뢺뗄춶쿮쒿뗄뿉쓜탔뻍풽듳ꆣ 막뚫쒿뇪닮틬쾵쫽뇤뮯뛔웳튵맽뛈춶랢짺뿉쓜탔뗄펰쿬풴폚컒맺짏쫐웳튵뗄막좨훆뛈낲업ꆣ퓚쿖폐뗄막좨훆뛈낲업쿂ꎬ늻춬탔훊막좨뗄돖폐헟횮볤뗄쒿뇪닮틬쾵쫽풽킡ꎬ틢캶ퟅ막뚫횮볤뗄쒿뇪닮틬풽듳ꆣ늻쓜ퟔ평쇷춨뗄맺폐막막뚫룼볓쟣쿲폚ힷ쟳맺폐닺뗄퓶횵ꎬ쓜릻ퟔ평쇷춨뗄룶죋막막뚫퓲룼볓쟣쿲폚ힷ쟳막좨춶뗄놾샻뗃ꆣ헢퇹ꎬ웳튵막욱뗄쫐뎡볛횵뻍믡퓚룶죋막막뚫놾샻뗃춶탨쟳퓶볓뗄쟩뿶쿂놻룟맀ꎬ쪹웤듳럹뛈뗘욫샫웳튵닺볛횵ꎬ웳튵튲뻍쓜릻틔뷏룟뗄쫐뎡볛룱랢탐탂막ꎬ믱뗃탂막랢탐뗄틧볛쫕틦ꆣ평폚틧볛쫕틦퓚웳튵춶훐쯹닺짺뗄볛횵놻쯹폐막뚫릲춬럖쿭ꎬ듓뛸풭폐막뚫쫂뫳럖엤뗄웳튵닺볛횵뷏웤놾펦뗃떽뗄늿럖퓶볓ꎬ뛸탂막막뚫떥캻놾춶뗄쫕틦붵뗍ꆣ떱웳튵듓랢탐탂막훐믱뗃뗄틧볛쫕틦듳폚탂춶쿮쒿쯹랢짺뗄춶뿷쯰쪱ꎬ듺뇭맺폐막막뚫샻틦뗄웳튵뺭펪맜샭헟죔쓜릻쪵쪩춶쿮쒿ꎬ맽뛈춶쿖쿳랢짺ꆣ???쇹ꆢ?뷡싛??춨맽놾컄뗄짏쫶럖컶ꎬ컒쏇뿉틔뗃떽틔쿂벸룶랽쏦뗄뷡싛ꎺ?ꋙ퓚춬막춬좨뗄막좨훆뛈쿂ꎬ죧맻췢늿춶헟폫웳튵쓚늿뺭펪맜샭헟횮볤듦퓚ퟅ폐맘웳튵춶쿮쒿풤웚뺻쿖뷰쫕틦쇷랽쏦뗄탅쾢늻뛔돆ꎬ웳튵샻폃막좨죚쪵쪩춶쿮쒿쪱ꎬ폐뿉쓜랢짺듺뇭풭폐막뚫샻틦뗄웳튵뺭펪맜샭헟쪵쪩뺻쿖횵캪뢺뗄춶쿮쒿뗄맽뛈춶탐캪ꆣ?ꋚ벴쪹늻뾼싇탅쾢늻뛔돆컊쳢ꎬ컒맺짏쫐웳튵춬막늻춬좨ꆢ쇷춨막뇈샽욫뗍뗄막좨훆뛈낲업쿂뗄막욱쫐뎡볛횵맽룟욫샫웳튵닺볛횵ꆢ막뚫탐캪쒿뇪닮틬뗈틲쯘튲믡떼훂웳튵퓚샻폃막좨죚쪵쪩춶쿮쒿쪱ꎬ랢짺맽뛈춶탐캪ꆣ?ꋛ퓚춬쪱뾼싇탅쾢늻뛔돆뫍컒맺짏쫐웳튵쳘쫢막좨훆뛈낲업뗄쟩뿶쿂ꎬ폫뷶뾼싇탅쾢늻뛔돆틲쯘뗄돉쫬횤좯쫐뎡짏춬막춬좨웳튵막좨죚쿂뗄춶탐캪쿠뇈ꎬ컒맺짏쫐웳튵막좨죚쿂맽뛈춶랢짺뗄뿉쓜탔튪듳뗃뛠ꆣ헢튲쫇컒맺짏쫐웳튵맽뛈춶탐캪웕뇩랢짺뗄훷튪풭틲횮튻ꆣ?ꋜ퓚탅쾢늻뛔돆뫍짏쫐웳튵쳘쫢막좨훆뛈낲업춬쪱듦퓚뗄쟩뿶쿂ꎬ탅쾢늻뛔돆틲쯘떼훂뗄탂막막뚫퓚쿮쒿춶뫳웳튵닺볛횵훐뗄럖엤뇈샽풽뗍ꎬ웳튵맽뛈 11
춶랢짺뗄뿉쓜탔풽듳ꎻ춬퇹뗘ꎬ컒맺막좨훆뛈낲업떼훂뗄막뚫쒿뇪닮틬풽듳ꎨ쒿뇪닮틬쾵쫽풽킡ꎩꎬ웳튵맽뛈춶랢짺뗄뿉쓜탔튲풽듳ꆣ????닎뾼컄쿗?믆짙낲ꆢ헅룚ꎬ2001ꎺꆶ훐맺짏쫐릫쮾막좨죚욫뫃럖컶ꆷꎬꆶ뺭볃퇐뺿ꆷ뗚11웚ꆣ 엋쏴ꎬ2001ꎺꆶ죚랽쪽ꆢ뷰죚웵풼폫릫쮾훎샭믺훆ꆷꎬꆶ뺭볃움싛ꆷ뗚5웚ꆣ 쳯횾쇺ꆢ퇮믔ꆢ샮폱쟥ꎬ1998ꎺꆶ컒맺막럝릫쮾훎샭뷡릹뗄튻킩믹놾쳘헷퇐뺿ꆪ뛔컒맺냙볒막럝릫쮾뗄쪵횤퇐뺿ꆷꎬꆶ맜샭쫀뷧ꆷ뗚2웚ꆣ 컄뫪ꎬ1999ꎺꆶ죚욫뫃폫죚킧싊ꆷꎬꆶ떱듺뺭볃뿆톧ꆷ뗚6웚ꆣ 풬맺솼 ꆢ횣붭뮴ꆢ뫺횾재ꎬ1999ꎺꆶ컒맺짏쫐릫쮾죚욫뫃뫍죚쓜솦쪵횤퇐뺿ꆷꎬꆶ맜샭쫀뷧ꆷ뗚3웚ꆣ 헔쫘맺ꎬ췵퇗퇗ꎬ1999ꎺꆶ엤막뗄뺭볃톧럖컶ꆷꎬꆶ떱듺뺭볃뿆톧ꆷ뗚6웚ꆣ Harris, M., and A. Raviv, 1991, ꆰThe Theory of Capital Structure,ꆱJournal of Finance 46, 297-355. Heinlkel, R. and J. Zechner, 1990, ꆰThe Role of Debt and Preferred Stock as a Solution to Adverse Investment Incentives,ꆱJournal of Financial and Quantitative Analysis 25, 1-24. Jensen, M. C., 1986, ꆰAgency Cost of Free Cash Flow, Corporate Finance and Takeovers,ꆱAmerican Economic Review 76, 323-339. Jensen, M. C, and W. Meckling, 1976, ꆰTheory of the Firm: Managerial Behavior, Agency Costs, and Capital Structure,ꆱJournal of Financial Economics 3, 305-360. Myers, S. C., 1984, ꆰThe Capital Structure Puzzle,ꆱJournal of Finance 39, 575-592. Myers, S. C., and N. S. Majluf, 1984, ꆰCorporate Finance and Investment Decisions When Firms Have Information That Investor Do Not Have,ꆱJournal of Financial Economics 13ꎬ187-221. Narayanan, M. P., 1988,ꆰDebt vs Equity under asymmetric Information,ꆱJournal of Financial and Quantitative Analysis 23, 39-51. 12
