Luận văn Áp dụng khai khoáng dữ liệu đề xuất một mô hình phát triển lợi nhuận của một ngân hàng

10 CHUaNG2: I LYTHUYETT!PH(jP THO vA cAc UNG DT)NGTRONG PHAN TicH DU LI}tU Trongchudngnayseduaracac9tudngcdban v~19thuye't~phQptho- mQt phudngphaptinh loan moi d~phantichdIT1i~u.xa'pXl duoiva trencuamQtt~p " hQp,cacloantll'cdbancua19thuye't,1acacsl!gioi thi~uband~uvadinhnghIa hlnhthli'c.Vai li'ngdl,mgcua19thuye'tt~phQpthoduQCtrinhbay tomHitvavai va'nd~trongtudng1aiclingduQcphacthao. L9 thuye't~phQptho( Pawlak,1982)[3]duaramQtcachphudngphaptinh loanmoid~phantichdITli~uvakhaikhoangdITli~u.Saunhi~unamphattri~n, 19thuye'tdad~tduQcdQchinmu6i.TrongnhITngnamg~ndaychungtadachli'ng kie'nmQtsl!tangtrudngnhanhchongtrong19thuye'tt~phQpthovacacli'ngdl,mg cuano trenloanthe'gioi.Nhi~uhQithao,hQinghiquO'cte'vacacseminarv~19 thuye't~phQpthotrongcacchudngtrinh.MQtsO'IOncactai li~uco cha't1uQng cao daduQcphathanhg~ndaytrennhi~ukhiac~nhcuacact~phQptho.Khai ni~mv~t~phQp1akhaini~mcanbancholoanbQtinhloandudngthaiva 19 thuye'tv~t~phQpduQcGeorgCantord~xua'tvaonam1883r6 rang1acQtmO'c trongvi~cphattri~ncachsuyfighTtinh,loanhi~nd~i. MQtt~phQpduQcxacdinhbdicacph~ntll'cua no,nghIa1anoduQcxac dinhne'umQiphffntll'cuano1axacdinhduynha't.Thi d1,l,t~phQpcua ta'tcacac sO'chan(Ie)1axacdinhduynha'tvam6imQtsO'nguyencoth~duQcphanbi~tma khongco sl!nhffm1iln,nhu1ach~nva Ie. Lo~ikhaini~mnay thuangduQcbie't 11 de'nnhula crisp(stfr5rang).Hi~nnhien,aftcacackhaini~mtinhtoanla crisp, ne'ukh6ng,thinokh6ngth~dungd~chungminhbfftky ly thuye'ttinhtoannao. \ Nhungrfftnhi~ulInhvtfckhac,tlnhhu6nglakh6ngr5rang.Trongy khoa, thi dl;1,khaini~mmQtnguBi"m<;tnhk oe( ho~cb~nh)" kh6ngth~dinhnghIa mQtcachduynhfft.Tuongttf,tronglu~tphapkhaini~m"cotQi"(ho~c"kh6ngco tQi") kh6ngth~'dinhnghIamQtcachchinhxac.Nhii'nglo<;tikhai ni~mkh6ng chinhxacnayduQcgQila mB (vague).Cackhaini~mmBkhan6i tie'ng,kh6ng chi trongy khoaho~clu~tkhoa,nhunghffuhe'tmQinoi,thidl;1,kinhte'vachinh tri la nhii'ngmi~nd~nchungdi~nhinhkhac,noicackhaini~mmBla thanhphffn banchfftchocacphuongphapsuyfighTvatranhdE. Cac khaini~mmBbi~uthibdi mQt "vunggidi h<;tn"(boundaryregion), nobaag6mtfftcacacthanhphffnmakh6ngth~duQcn6ike'tvdikhaini~mho~c phffnbucuakhaini~m.Thi dl;1,khaini~mv~mQtconso'chan (1e)la chinhxac, bdivi mQtcons6thila chanho~cIe, trongkhidokhai ni~mv~caidypthimo h6bdivi kh6ngth~quye'tdinhmQtcachkhachquailmQithula dyphaykh6ng. PhuongphapduQcbie'trongvanchuangtrie'thQcnhula phuongphapcoduBng gidih<;tnchotinhmBvala thuQCv~ nhalogicDucGottlobFrege,nguBidffutien hinhthanhtu'tudngnayvaonam1984.Theocachdo, cackhaini~mmBhinh thanhcosdcholy lu(iny thacchungtrongnhi~ulInhvtfclienh~ voinhi~utlnh hu6ngtrongthtfcte'. Tinh mBnhi~unamthuhutstfchuycuacacnhalogicva trie'thQC.Gffn day,cacnhakhoahQcmaytinhclingconhi~unghienCUutronglInhvtfcnay, 12 nhi~ulingdl;!ngmayHnh,noirieng,nhula "tri tu~nhant<:lO",dn sii' dl;!ngcacI khaini~mmavaphuongphaply l~n din cu trenkhaini~mmo. Phuongphaply thuye'tthanhcongnhfitv~tinhmala lythuye'tv~t:\ipma dU<;fcd~nghibdiZadeh.Y tudngcobancualy thuye't:\iph<;fpmaxoayquanh trenhamthanhvienma,manochophepmQtphftncuacacphftntii'thuQcv~ mQtt:\iph<;fpnghiala no chophepcacphftntii'thuQcvaomQtt:\iph<;fptheomQt "mucdQ" Ly thuye't:\iph<;fpthola mQtphuongphap Hnhtoankhaccua Hnhmo. Trangphuongphapt:\iph<;fpthoHnhmanghlala thie'ucacthongtinv~vaiph~n tii'cuat:\ipvutrl;!. Ne'uclingmQtthongtinmalienquailtdi vai ph~ntii',trongph<:lmvi cua thongtin nay,nhungphftntii'nayla kh6ngthi phanbi~tduf!c.Thi dl;!,ne'uvai b~nhnhanbi m~cclingmQtdin b~nhcl;!th€ th€ hi~nclingmQtri~uchung,hQla khongth€ phanbi~tdU<;fcd6ivdi thongtin v~hQ.Hoara dingHnhkhongth€ phanbi~tdu<;fcd~nde'ncac truangh<;fpv~vling gioi h(,ln,nghla la, vai ph~ntii' khong thS ke'tn6i vdi mQtkhai ni~mhoi;icph~nbli cua khai ni~m nay trong ph<:lmvi cuathongtincosan.Bdi VIcackhaini~mmacocactru'angh<;fpvling gidi h<:ln,ghlala cocacph~ntii'makhongthSphanbi~tla noco chinhxacla ph~ntii'cuakhaini~mhaykhong,Hnhmala lienh~tn!ctie'phoantoan vdiy tudngcuastfch~c h~n(hoi;ickhongch~ch~n). Ly thuye't:\iph<;fph<;fpthoco ve rfitthichh<;fpnhula mQtmohlnhHnh toanchoHnhmavastfkhongch~cch~n.Tinhmala mQtthuQcHnhcua t:\iph<;fp 13 (khai ni<$m)va n6 lien quail hoantoande'nslf hi<$ndi<$ncua vung gioi hC;lncua, mQtt~phQp.NguQc1C;lislfkhongcha:ccha:n1amQtthuQctinhcuacacphftntii'cua cac t~phQp.Trong phuongphapt~phQptho ca hai khai ni<$m1alien quail gftn gili bai VI tinhkhongphanbi<$tduQCgayra bai thie'uthongtinv€ the'gioi ma chungtaquailtamde'n. Slfke'thQpcua1ythuye'tt~phQpthovanhi€u 1ythuye'tkhacdfitranenr6 rang.N6i r6 hon1am6ilienh<$giil'a1ythuye'tt~phQpmava1ythuye'tDempster - Shaferv€ tinhr6 rang.Khaini<$mcuat~phQpthovat~phQpma1akhacnhau bai VI chungbi€u di€n cackhiaqnh khacnhaucuacuatinhmoh6 (Pawlak& SLowron 1994),nguQc1C;lislf n6i ke'tvoi 1ythuye'tv€ tinh chungcu 1adin ban hon (Skowron & Gizyma1aBusse, 1994).Hon nil'a,1ythuye'tt~phQptho lien quailde'nslf phantichbi<$tso'(Krusinskava AI.,1992),phuongphap1u~n1y (Skowron& Rauszer,1992),vanhil'ngphuongphapkhac.M6i quailh<$giil'aly thuye't~phQptho va phantich quye'tdinh duQcgioi thi<$ubai Pawlak& SLowinski(1994)va SLowinski(1995).Nhi€u ma rQngkhacv€ mo hlnh1y thuye'tcuat~phQpthodangduQcd€ xua'tvaphathi<$nthem. Ly thuye'tt~phQpthoc6ra'tnhi€u lingdl;!ng.Phuongphapt~phQpthodfi 1acongCl;!quail tn;mgtronglInh vlfc tri tu<$nhantC;lOva cac lInh vlfc lien quail de'nnh~nthuc,d~cbi<$ttronglInh vlfc may hQc,truy va'n kie'nthuc,phan tich quye'tdinh,khamphakie'nthuctUcosadil'1i<$u,h<$th6ngchuyengia,1y1u~nquy nC;lpva nh~ndC;lngm~ug6mnh~ndC;lngtie'ngn6i va chil'vie'ttay.N6 ra'tquail trQngchocach<$th6ngra quye'tdinhvakhai khoangdil'1i<$u.LQi the'chinhcua1y thuye't~phQptho1an6 khongdn ba'tky thongtin sobQva themvaov€ dil'li<$u - nghla1agi6ngnhukhanangtrongth6ngke, trongphancongcua 1ythuye't 14 Dempster- Shafer,ca'pb~cthanhvienho~cgiatQcuakhanangtrongly thuye't t~ph<;5pmo.Ly thuye't~ph<;5pthoda thanhcongkhi dapling trongnhi~uva'nd~ v~th1.!cte'trongy khoa,dU<;5ckhoa,xayd1.!ng,nganhang,taichinhvaphantich thjtruong,...E>~cbic$ttronglInhv1.!cdu<;5ckhoas1.!phantichm6iquailhc$giuaca'u truchoa hQCva hoC;ltdOngch6ngvi trung cua thu6cdangdu<;5cxuc tie'nra'thic$u qua.Cac ling dl.mgtrongnganhangbaa g6mdanhgia cac rui ro va nghienCUu thj truongdang thu du<;5cnhi~uke'tqua t6t va ngay dng gianh dU<;5cs1.!thita nh~n. Phuong phap t~ph<;5ptho cling quail trQngtrong nhi~uling dl.mgthuOc khoahQcxay d1.!ngnhula nghiencUu,chuffndoanmaymocsadl,mgcacda'uhic$u v~dO6n djnh (tie'ng6n,s1.!rung),vas1.!di~ukhi~ncactie'ntrinh.Caclingdvng trongngonngu,moitruong,vacosCJdulic$ula caclInhv1.!cquailtrQngkhac.Ra't nhi~uhilah~nla cacIInhv1.!cmoicuacaclingdvngcuakhainic$mt~pthosen6i len trongtuonglai gfin.Chungbaag6ms1.!di~ukhi~ntho,cosCJdulic$utho,rut trichthongtintho,mC;lngthfinkinhthovacaclInhv1.!ckhac. Cac ling dvng cua t~ph<;5ptho yell du phfin m~mthich h<;5p.Nhi~uhc$ th6ngphfinm~mcho cac workstationva may PC, can cu tren ly thuye'tt~ph<;5p tho,dangphattri~n.Cac sanphffm n6i tie'ngnha'tbaag6mLERS (Gizymala- Busse,1992),RoughDAS andRoughClass(SLowinski& Stefanoski, 1992)va DATALOGIC (Szladow,1993).Vai caidaduQcthuongmC;lihoa. 15 2.1.Y TU<1NGCO BAN Y tu'dngcua t~phQpthodljatft?nsljthuanh~nding,tniivoi ly thuye'tvS t~phQpc6diSn,chungWicovaithongtinthemvao( kie'nthuc,dli li~u)vScac ph~ntti'cuamQtt~phQp.Noi ra hon,thid\)nhu',mQtnhomcacb~nhnhanbi dati tuclingmQtdin b~nh.Trongb~nhvi~ndangdiSutri cacb~nhnhannaycocac file dli li~uchua"cacthongtinvSb~nhnhan nhu'lathannhi~t,aplljc mali,ten, tu6i,diachi,...Ta'tcab~nhnhanbQclQclingtri~uchungla thongthi phiinbi?t dU(lC(gi6ngnhau)trongph~mvi cuathongtincosanva t~othanhcackh6i,ma noco thSdu'QchiSunhu'la cacmllunhocua kie'nthucvSb~nhnhan(ho~clo~i b~nhnhan).Cacmllunhonaydu'QcgQila cactqpcdban (elementarysets)ho~c cackhai ni~m(concept),vacothSdu'Qcbie'tnhu'lacackhol xaydI1ngcdban (nguyentti'- atoms)cuakie'nthucchungtavS diSumachungtaquailtamde'n. Cac khai ni~mco banco thSke'thQpvao cacthai ni?m da h(lp (compound concepts)nghlala cackhaini~mdu'Qcxacdinhduynha'tronggiOih~ncuakhai ni~mcoban.Ba'tky sljke'thQpcuacact~phQpcobandu'QcgQila t~pra (crisp), vaba'tky t~phQpnaokhacthldu'Qchola tho(mo,khongchinhxac).Voi mQi t~pX chungtacothSlienh~hait~pcrispdu'QcgQilaxiipxi dumvatrencuaX. xa'pXldu'oicuaX la ke'thQpta'tcacact~phQpcobanmanothuQcvS X, ngu'Qc l~ixa'pXltrencuaX la hQpcuata'tcacact~pcoban,ma giaokhacr6ngvoiX. Noi cachkhacxa'pXl du'oicuamQtt~phQpcuata'tcacacph~ntti'mano cha:c cha:nph\)thuQcvaoX, ngu'Qcl~it~pxa'pXl trencuaX la t~pta'tcacacph~ntti' manocokhaniingthuQcvaoX. Slj khacbi~tcua xa'pXl trenvadu'oicuaX la vimggiai h{m.HiSnnhien, mQtt~pla tho ne'uno khongco vlinggioi h~nr6ng; ngoaifa, t~phQpla ra 16 (crisp).Cac ph~ntli'cuavunggidi h~nthl khongth~phanbi~tdu'<;Jc,sli'dl;mg kie'nthliccosan,1anothuQcv€ t~ph<;Jpho~cph~nbucuat~ph<;Jp.Slj xa'pXlcua cac t~ph<;Jp1atoantli'co ban trang19thuye't~ph<;Jptho va du'<;Jcsli'dl;mgnhu'1a congCl;lchinhd~d6i phovdi dli li~umava dli li~ukhongch~cch~n. 2.2.THI DT) HaychochungtoiminhhQa9tu'dngbell trenb~ngphu'ongti~n1amQt thi dl;ldongian.Dli li~uthu'angdu'<;JctrlnhbaytrangmQtbang,caccQtcuanodu'<;Jc d~ten1athuQctinh,cacdong1acacd6itu'<;Jngvacacth~hi~ncuabang1agiatri cuacacthuQctinh.Cac bangnhu'the'du'<;Jcbie'tnhu'1acach~th6ngthongtin,cac banggiatricacthuQctinh,cacbangdli1i~u,ho~c1acacbangthongtin. Trangcacbangthongtinchungtoi thu'angphanbi~tgiliahai lo~ithuQc tinh,du'<;Jcd~ten1adi€u ki~nvaquye'tdinh.Nhlingbangnhu'the'du'<;Jcbie'tnhu' 1abangquye'tdinh.Cac dongcuabangquye'tdinh du'<;Jcbie'tnhu'1acac quy1u~t quye'tdinh "ne'u...thL", ma no cling ca'pcac di€u ki~ndn thie'td~t~olien cac quye'tdinhdinh bdicacthuQctinhquye'tdinh.Bang2.11amQthidl;lv€ mQtbangquye'tdinh. 17 Bang2.1:bangquye'tdinh, Bangchuacacdfi'1i~ulienquailde'n6 duong6ngb~ngsa:tdu<jcki~mtra , khanangchiliapsua'tcao.TrongbangC,S va P la cacthuQctinhdiSuki~n,th~ hi~nnQi dungph~ntram than da (Coal), sul-phur(Sulfur), va ph6t-pho (Phosphorus),riengtungcai,ngu<jcl~ithuQctinhNUt th~hi~nke'tquacuavi~c ki~mtra.Gia tri cuathuQctinhdiSuki~nla nhusau(C, cao» 3,6%,3,5%~ (C,TB) ~3.6%,(C,tha'p)<3.5%,(S,cao)~0,1%. (S,tha'p)<0.1%, (P,cao)~0.3%, (P,tha'p)<0.3%. Va'ndS chinhchungta quailHimla st!chili dt!ng nhuthe'naocuacac du'ong6ngphl;!thuQcvaot6 h<jpC,S vaP ke'th<jptrong10,ho~cnoicachkhac, cohaykhong mQtphl;!thuQchamgifi'athuQctinhquye'tdinhNUt vacacthuQc tinhdiSuki~nC,S va P. Trongngonngfi'ly thuye't~ph<jptho,di~mquailtam ma'uch6tla t~ptrungvaocalihoikhongbie'tr~ngt~ph<jp{2,4,5}cuata'tciicac duong6ng khong co ve'tnut sauki~mtra ( ho~cla t~ph<jp{1,3,6}cuacac Duong6ng C S P Nut 1 Cao Cao Tha'p Co. 2 TB Cao Tha'p Khong 3 TB Cao Tha'p Co 4 Tha'p Tha'p Tha'p Khong 5 TB Tha'p Cao Khong 6 Cao Tha'p Cao Co 18 du'ong6ngcove'tnut),coth€ dinhnghladuynha'tronggioih(;lncuacacgiatri, thuQctinhdi@uki~nkhong. Co th€ d~dangnh~ntha'yr~ngdi@udolakhongth€, baiVI6ng2 va3 th€ hi~nrungd~cdi€m tronggiOih(;lncuathuQctinhC, S vaP, nhu'ngcogiatrikhac nhaucua thuQctinhNut.Do dothongtindu'Qcrhotrongbang2.1la khongd~y dud€ giaiquye'tva'[email protected],coth€, dusao,rhomQtgiaiphap bQph~n.ChungfahayquailsatthuQCtinh C cogiatri CaorhomQtdu'ong6ng, r6i thldu'ong6ngnut,ngu'Qcl(;line'ugia tri cuathuQctinhC la Tha'p,thldu'ong 6ngkhongbi nut.Do do,sad\)ngthuQCtinh C, S vaP chungtacoth€ noir~ng cacdu'ong6ng1va6 la ch3:ch3:nt6tnghlala tinh ch3:ch3:nph\)thuQcvaot~p (1,3,6),ngu'Qcl(;licacdu'ong6ng1,2,3 va6 la cokhanangt6tnghlala cokha nangph\)thuQcvaot~p(1,3,6).Do dot~p(1,6),( 1,2,3,6),va(2,3)la xa'pXldu'oi, tren,vavunggiOih(;lncuat~p(1,3,6),riengbi~ttungt~pmQt. £>i@udo co nghlala cha'tlu'Qngcuadu'ong6ngkhongth€ du'Qcxacdinh chinhxacbai nQidungcuathanda,sul-phurva ph6t-photrong10,nhu'ngcoth€ du'Qcxac dinh mQtcach xa'pxl. Tht!c te'thl, st!xa'pXl xac dinh st!ph\) thuQc (toanph~nho~cmQtph~n)giuacac thuQctinhdi@uki~nva quye'tdinh,nghlaIa m6iquailh~r6 ranggiuacacthuQctinhdi@uki~nvaquye'tdinh.Muc dQcuast! ph\)thuQcgiuacacthuQctinhdi@uki~nvaquye'tdinh coth€ dinhnghlanhu'lat1 1~giua ta'tcacacdongmagiatri cuathuQctinhdi@uki~nxacdinhduynha'tgia tri cuacacthuQctinhquye'tdinhva ta'tcacacdongtrongbang.Thi d\),mucdQ cuastfph\)thuQcgiuacacve'tnut vast!ke'thQpcac6ngs3:tla4/6=2/3.Co nghla la4/6(xa'pXl66%)cac6ngcoth€ phanbi~tdungd3:nla t6ttrencdsast!ke'thQp ? ,cua no. 19 Chungtaco th~clingquailHimde'nvi~cgiamvai thuQctinhdi~uki~n, \ nghIala cohaykhongvi~cta'tcacacdi~uki~nladn thie'td~t~oracacquye't dinhmotatrongbang.D~giaiquye'tnochungtasesadl;mgkhaini~mv~mQt slj thunho (cacthuQctinhdi~uki~n).B~ngslfthunhochungtatimduQcmQt~p connhonha'tcuacacthuQcHnhdi~uki~nmanococlingca'pdQcuaslfphlJthuQc giil'acacthuQctinhdi~uki~nvaquye'tdinh.De dangd~Hnhroanr~ngtrong bang2.1chungtacohaicaithunho,d~tenla (C,S)va(C,P).Giao ta'tcacac thunhoduQcgQila core.Trongthi dlJ cuachungta,corela thuQcHnhC mano conghIala trongph~mvi cuadil'li~u,thandala lInhvlfcquailtrQngnha'tgayra ve'tnutvakhongth~duQclo~itnrkhoislfquailtamcuachungta,nguQcl~i,Sul- phurvaPh6t-phodongmQtvaitrothuye'uvacoth~duQcthayd6ilin nhaunhu la lInhvlfcgayrave'tnut. 2.3.TINHKHONG THE PHAN BItT DU<jC NhudaduQcd~c~ptrongph~ngidithi~u,di~mkhaid~ucua19thuye't~p hQptholam6iquailh~khongth~phanbi~tduQc,sinhrabaithongtinv~cacd6i tuQngmataquailtam.M6i quailh~khongth~phanbi~tduQcnglJ9dug dothie'u kie'nthucmachungtakhongth~phanbi~tduQcvaid6ituQngtrencosathongtin cosan.Di~udo conghIar~ng,noichung,chungtakhongchI giaiquye'tcacd6i tuQngriengIe macon phaiquailtamde'nnhomcacd6ituQngkhongth~phan bi~tduQcnhula cackhaini~mcobanv~kie'nthuc. Bay giOchungtanoir6 honv~di~uquailtambelltren.Gia sli'chungta duQcchohai t~phQpxacdinh,khongr6ng,U vaA, U la tqpvii trq vaA la tqp caethul)ctinh.VOi m6ithuQcHnhathuQcA, chungtalienh~vdit~pVa cuacac 20 giatri cuanoduQcgQilamiencuaa.Ci,ipS=(U,A)seduQcgQilamQth~thO"ng thongtin. Ba'tcut~pconB naocuaA xacdinhm6iquailh~haingoiIB trenV, seduQcgQila molquanhf thong thi phlin hift dll(1C,va duQcdinhnghlanhu sau: XIBy ne'uvachine'ua(x)=a(y)voimQiathuQcA trongdoa(x)kyhi~ugiatricuathuQctinhacuaph~ntti'x (2.1) HitinnhienthlIB la mQtm6iquanh~tuongduong.T~phQpcuata'tcacaclOp tuongduongcuaIB,nghlala duQcxacdinhmQtph~nbdiB, seduQcky hi~ubdi VIIB ho~cdongianla VIB ; mQtlOptuongduongcuaIB nghlala kh6icuaph~n U/B chuax seduQckyhi~ulaB(x). Ne'u(x,y)thuQcv6IB chungtase noidingx vay la B-khongthi phlin hift dll(1c.Cac lOpWongduongcuam6iquailh~ IB (ho~cla cackh6icuaph~n UIE) thlduQcbie'tnhulaB- cdhim ho~claB-sdclip.NhudaduQcd6c~ptruoc daytrongphuongphap t~phQptho,khaini~mcoban la cackh6ixay dl;l'ngco ban (khai ni~m)cuakie'nthucchungtav6 the'giOithl;l'c.D6i voi thi d~,cac duong6ng1,2 va 3,clingnhula cacduong6ng5 va 6 la khongth~phanbi~t duQctronggioih<;lncuaS vaP, duong6ng1va6 cling nhula 2,3va5 la khong th~phanbi~tduQctronggioih<;lncuathuQctinhC. 21 K ?, A 2.4.STjXAP XI CAC T~P H(1P M6i quailhc$khongthephanbic$tdu<;1csedu<;1csli'dl,mgke'tie'pdedinh nghlacackhainic$mco banv€ ly thuye'tt~ph<;1ptho.Baygiochungtahaydinh nghlahai toantli' trent~ph<;1pnhusau. B*(X)={x E U: B(x)c X} * B (X)={XEU: B(x) n X :;t:0} (2.2) Hai toan tli'nay gall cho m6i t~pcon X cua t~pvu trl;lU hai t~ph<;1p,B*(X) va B*(X), gQila B-xiip xi du:oivaB-xilp xi trencua x, riengtungcai mQt.T~ph<;1p BNg(X)=B*(X) - B*(X) (2.3) Se du<;1cbie'tde'nnhula vimggiUihfJ-nB cuaX Ne'uvunggioi h~ncuaX la t~pr6ng,nghlala BNg(X) =0, thl t~pX la ro (crisp) d6i voi B; trongtruongh<;1pngu<;1cl~i,nghlala, ne'uBNB(X):;t:0, t~p h(khong ra) d6i voi B Thi dl;lsaudaysechIra lamcachnaodetinhtoanvungxa'pXlduoi,tren vavunggioih~ncuamQtt~ph<;1p.Hay kyhic$ut~pcacthuQctinhdi€u kic$nC,S, vaP b~ngB, vaky hic$uXC6={1,3,6},XKh6ng={2,4,5}Ia cact~pcuaduong 6ng bi nutvakhongbi nut,riengbic$t,cact~pB-coban trongthidl;l la cact~p sauday:{I},{2,3},{4},{5},va {6}.Dodo,chungtaco: B*(XC6)={I}U {6}={1,6} B*(XC6)={l}U {2,3}U {6}={I, 2,3,6} B*(XKh6ng)= {4}U {5}= {4,5} 22 * B (XKh6ng)={2,3}U {4}U {5}={2,3,4,5} BNg(XCo) = BNg(Xkh6ng)= {2,3 } (2.4) C6th~dSdangchIfacactinhcha'tcuatinhxa'p xl. 1. B*XcXcB*X 2. B*(0) = B*(0) = 0; B*(U)=B*(U)=U 3. B* (Xu Y) = B*(X) u B*(Y) 4. B*(X n Y ) = B*(X) n B*(Y) 5. X c Y baahamla B*(X) c B*(Y) vaB*(X) c B*(Y) 6. B*(X u Y ) ;;;;? B*(X) u B*(Y) 7. B* (X n Y) c B*(X) n B*(Y) 8. B*(-X)=- B*(X) 9. B* (-X)=- B*(X) Trangd6- X lakyhi~uU-X 10.B*B*(X) =B* B*(X) =B*(X) l1.B* B*(X) =B*B*(X) =B*(X) Nh<\inxetdingbdiVIthuQctinh6va7,cacxa'pXlkhongth~tinhtoantung budc,bdiVIxa'pXldudicuahQinhi~ut<\iph<;1pla chua hQicuanhi~uxa'pXl dudi cuatUngt<\iph<;1pthanhph~n; tudngtlf nhuv<\iy,xa'pXl tfen cuagiao cua cac t<\iph<;1pchuatranggiao cua xa'pXl tfen cua cac t<\iph<;1pthanhph~n.C6 nghIala, n6i chung,bangdii' li~ukhongth~chiathanhcacph~nnh6hdn (ho~ccacbangkhongth~dU<;1cgoml<,tivdi nhau),ke'tquac6 dU<;1ctu cac bangdi'ichia fa ho~cgom l<,tic6 th~khac. C6th~dinhnghIa4ldpdin bancuat<\iptho,nghIala4 lo<,ticuatinh ma: 23 a) B*(X):;t:0vaB*(X) * U, ne'ux la B-coth€ xacdinhduQcvakhong chinhxac b) B*(X)=0vaB*(X)*U,ne'ux laB-khongth€ xacdinhduQc vabell trong c) B*(X)*0 va B*(X)=U,ne'ux la B-co th€ xacdinhduQCva tubell ngoai. d) B*(X)=0vaB*(X) =U, ne'ux laB- hoantoankhongth€ xacdinh duQc Y nghIatn,icgiaccuacacphanlo~inaylanhusau . Ne'uX la B-coth€ xacdinhduQCvakhongchinhxac, conghIala chungtacoth€ quye'tdinhvaiph~ntii'cuaU ho~cla thuQcX ho~c-X sii'dlJngB . Ne'uX laB-khongth€ xacdinhvabelltrang,conghIala chungtaco th€ quye'tdinhvaiph~ntii'cuaU thuQcv€ -X, nhungchungtakhong th€ quye'tdinhchoba'tky ph~ntii'naGcuaU, ho~cno thuQcv€ X ho~ckhongsii'dlJngB . Ne'uX la B-khongth€ xacdinhtubellngoai,conghIala chungtaco th€ quye'tdinhvaiph~ntii'cuaU ho~cla thuQcv€ X, nhungchungta khongth€ quye'tdinhba'tky ph~ntii'naGcuaU ho~cno thuQcv€ -X ho~ckhongsii'dlJngB. . Ne'uX la hoantoanB-khongth€ xacdinhduQc,chungtakhongth€ quye'tdinhba'tky ph~ntii'naGcuaU ho~cla nophlJthuQcVaGX ho~c - X sii'dlJngB 24 Trong thi dt,lcuachungta B*(XC6)"*U, B*( XC6)"*0 va B*(XKhOng)"*0 ; do do ca hai XC6 va XKh6ngla khong chinhxac va B-co th€ xac dinh duQc. T~phQpthocoth€ clingduQcbi€u thiblingcons6h~s6: as(X)= IB*(X) I IB *(X) I (2.5) duQcgQila dl)chinhxac cuasl;l'x~pxl, trongdo IXI ky hi~us6phftntil'cuaX. Hi€n nhien,a :::;aB(X):::;2.NC'uaB(X)=1,X la crispd6ivoiB ( X la ro d6ivoi B); ngoaira,nC'uaB(X)< I, X la khongchinhxac d6ivoiB. thidt,l,d6ivoiXC6 chungtaco: a B (XeD)=a B(Xkhong)=2/4 =1/2 (2.6) 2.5.T~PH<JPTHO vA HAM THANH VlEN T~phQpthocoth€ clingduQcdinhnghlablingcachsil'dt,lngillQthamthanhvien tho,dinhnghlanhusau: J1~(x)=IXnB(x) I IB(x)I (2.7) hi€n nhien: J1~(x) E[0,1] (2.8) 25 Gia tri cua ham thanhvien ,uf(x) la mQtlo<;lixac sufftdi€u ki~n,va co th€ du'QC hi€u nhu'la muc dQcua stfca quye'tvao stfki~nla x thuQcv€ X (ho~cla 1- J.!XB(X),la muc dQ cua stfkhong ch1:lcch1:ln.) Ham thanhvien thoco th€ du'QCsadl,mgd€ dinhnghIatinhxffpxi va vung gidi h<;lncuamQtt~pnhu'chi fa du'diday: B*(X) ={XE U: ,uf(x)=I}, B* (X) ={XE U: J.i%(x)>O}, BNB(X) ={XE U :O<,uf(x)<I}, (2.9) Ham thanhvien tho co nhil'ngthuQctinh sau day (Pawlak & SLowron, 1994): a) ,uf(x) =1ne'uXE B* (X); b) ,uf(x)=0 ne'uXE -B* (X); c) O<,uf(x)<1ne'uXE BNB (X); d) ne'u(B)={(x,x): x E U },thl ,uf(x) la hamd~ctfu'ngcuaX; e) ne'ux IBy thl ,uf(x)=,uf(y) xacdinh bdiIB; f) ,u~-x(x)=1- ,uf(x)vdimQix E U; g) ,ufuY(x)2 max(,uf(x)"u:(x)) vdi mQix E U; h) ,ufnY(x)~min(,u:(x), ,uf(x)) vdi mQix E U; i) ne'uX la t~pcacc~ptungdoi tach foi cuaU, thl ,u~x(X)=L x E X ,uf(x)vdi mQi x E U; 26 ThuQctinhtrenchi ra r~ngsVkhacbi~tgiuahamthanhviencuat~p, mava tho,N6i rieng,thuQctinhg) vah) chira r~ngcachamthanhvien thoc6th~ du'<;1cdanhgiachinhthucnhu'Ia svkhaiquath6a hamthanh vienmadotoantii'maxvamill rhophephQivagiaocuat~ph<;1p,Wang lingvoi, t~pmala cactru'angh<;1pd?cbi~tcuat~ptho.Nhu'ngchungta nhol~ir~ng"hamthanhvientho", lacai tu'angphanvoi "hamthanhvien IDa",thuQcv€ hu'angvi cuatinhxacsua't.Thi d\),hamthanhvienthocua cacdu'ang6ngrhoXC6la du'<;1cchiradu'oiday J.1~co(~)=1; J.1~C()(P2)= 1/2; J.1~cJ~) = 1/2; J.1~co (P4) = 0; J.1~co(ps) = 0; J.1~(P )=l'co 6 , (2.10) C6 nghlala ne'u,mQtdu'ang6ng c6 chuanhi€u thandel,sul-phurva it ph6t-pho,thln6nUt,ngu'<;1cl~ine'uthandel,suI-furva ph6t-phola trung blnh,nhi€u vait thlxacsua'td~du'ang6ngbinutla Yz C6 th~d~dangtha'yr~ngt6nt~imQtm6ilienke'tmongmanhgiua tinhmava tinhkhongcha:cha:n,Nhu'du'<;1cd€ ~ptru'ocdaytinhmalien quail t~ph<;1p(khai ni~m),ngu'<;1cl~i, tinhkhongcha:ccha:nlien quailde'n cacph~nttl'cuat~ph<;1p. 27 2.6.STjPHT)THUOCCUA cAe THUOCTINH \ Tinhxa'pxi cuat~phQpla lienquailch;}tcheWikhaini~mv~stfph\!thuQc(toan bQho;}ctung ph~n).B~ngtrtfcgiac,mQtt~pcacthuQctinhD phlj thul)cholm tolmvaomQt~pcacthuQctinhC,kyhi~ulaC =>D,ne'uta'tcacacgiatricua thuQctinhtuD xacdinhduynha'tb~ng iatricuacacthuQctinhtuC.Noicach khac, D ph\!thuQchoantoanvao C, ne'ut6n t<;limQtstfph\!thuQchamgiua gia tri cuaD va C. Trangbang2.1khongco ph\!thuQchoantoannao. Chungtaclingdn mQtkhaini~mt6ngquathancuastfph\!thuQcvaocac thuQctinh,duQcgQilaphlj thul)cml)tphiln cuathuQctinh.Ph\!thuQcmQtph~n conghlalachicovaigiatricuaD laduQcxacdinhbdigiatricuaC Thongthuongthl,stfph\!thuQcoth~duQcdinhnghlatheocachsau:xet D vaC la t~pconcuaA, chungtanoir~ngD ph\!thuQcvaoCd milcdQk (0~k ~1),kyhi~ula C ~k D, ne'u k =r(C,D) =IPOSe(D) I IVI (2.11) trangdo POSe(D)= YC.(X) (2.12) XEUID duQcgQila vungxacdinhcuathanhph~nDID d6ivdi C, la t~phQpcuata'tca ph~nph~ntti'cuaD manocoth~duQcphanbi~tduynha'tucackh6icuaph~n DID bdiC. Hi~nnhien: r(C,D) = L Ic.(X)I XEUID IV I (2.13) 28 Ne'uk =1chungtanoi r~ngD ph\!thuQcho~mto~mvaoC, vane'uk < 1, chungtanoiD ph\!thuQcmOtph~n(dmucdQk) vaoC. H~s6k noitenti 1~cuaHitcacacph~ntacuat~pvii tr\!manocoth~ phanbi~tr6rangtrongcackh6icuaph~nDID,sad\!ngthuQCtinhC,vasedu'Qc gQilamucdQcuaslfph\!thuQcmacoth~ciingdu'Qchi~unhu'laxacsua'tmax E U thuQcvemQttrongcactrongcaclopquye'tdinhxacdinhbdithuQctinhquye't dinh.Thi d\!:(slfnut)ph\!thuQcvao(C,S,P)d ca'pdQk =4/6=2/3.conghlalahai ph~nbacuadu'ang6ngcoth~phanbi~tr6rang la nUtho~ckhongb~ngcachsa d\!ngcacthuQctinhC,SvaP. 2.7.StjGIAM TRIEU cAe TRUQC TINR Chungtathu'angphaid6iphovoicallhoikhongbie'tcoth~bovaidii'ki~n titmOtbangdii'li~uvav§:nconduytri cacd~ctinhcdbancuanokhong, conghlalacohaykhongmOtbangchuavaithongtinvo dvng.ThidV,d~ dangtha'yr~ngne'uchungtaborakhoibang2.1ho~cthuQctinhS ho~c thuQctinhP, chungtaco du'Qct~pdii' 1i~utu'dngdu'dngvoi cai nguyen thuy,voi slfquantamvaocacxa'pXldu'oivamucdQcuaslfphvthuQc. Haygiaithichytu'dngnaychinhxachdn sauday.X6t C,D c A la cact~phQpcuacacthuQctinhdi€u ki~nvaquye'tdinhmOtcachphanbi~t. chungtase noi r~ngC'c C la mOtD-rutgQncua(rutgQnd6ivoiD) cua C, ne'uC' la t~pt6ithi~ucuaC saDcho: Y (C,D)=Y (C' ,D) (2.14) 29 Trangbang2.1,chungtacohait~prutgQn,(C,S)va (C,P),d6ivdi thuQc tinhNut.Co nghIalaho~cthuQctinhSho~cthuQctinhP cotheIO<;litrukhoibang va,VIv~y,thayvaobang2.1cothesad\mgbang2.2ho~cbang2.3. GiaocuatfftcacacD-rutgQngQilaV-core(cored6ivdiD).Bai VIcorela giaocuatfftcacacrutgQn,nola chuatrangtfftcacacrutgQn,nghIala m6iphffn tacuacorethuQcv~vairutgQn.Do do,corela t~pconvo rungquantrQngcua cacthuQctinh,khongcobfftky phffntii'naocuachungco thebi IO<;limakhong anhhuangde'nst!phanbi~tcuacacthuQctinh.Trangbang2.1corecua(C,S,P) d6ivdiNutlaC Bang2.2.RutgQncuabang2.1 Bang2.3.RutgQncuabang2.1 Duong6ng C S NUt 1 Cao Cao Co 2 TB Cao Khong 3 TB Cao Co 4 Thffp ThffP Khong 5 TB Thffp Khong 6 Cao Thffp Co Duong6ng C P NUt 1 Cao Thffp Co 2 TB Thffp Khong 3 TB Thffp Co 4 Thffp Thffp Khong 5 TB Cao Khong 6 Cao Cao Co 30 2.8.MATR~NPHAN BItT vA HAM D€ d~dangtinhtmlnsvgiamthi€u vacorechungtasesad\,mgmatr~nphan bi~t(SkwronRauszer,1992)machungtasedinhnghlasailday MQtmatr~nphanbi~tcuaB c A la matr~nn x n dinhnghlanhu'sau: 8 ( x,y)={a E B : a(x)*a(y)} (2.15) Do do8( x,y)la t~pcuata'tcacacthuQctinhmanophanbi~tcacd6i tu'Qngxvay. Matr~nphanbi~tcuabang2.1vat~phQpcacthuQctinhB =( C, S, P) la du'Qchotrongbang2.4.Ma tr~nphanbi~tgallchom6ic~pcuacacd6itu'Qngx vay, mQt~pconcuacacthuQctinh,8(x,y) c B, voicacthuQctinhsailday: a) 8( x,x)=0 b) 8( x,y)=8(y,x) c) 8 ( x,z)c 8( x,y)u 8 (y,z) Nhii'ngthuQctinhnaytu'dngtvvoibankhoangcach(semidistance),va,dodo ham 8 co th€ du'Qcbie'tnhu'la tlfa metricd€ do cha'tIu'Qng(qualitative semimetric)va8 ( x,y) 31 Bang2.4Ma tr~nphanbi~tchobang2.1 Tlfametricd€ docha'tluQng(qualitativesemimetric).Do domatr~nphan bi~t co th€ xem nhu la mOt ma tr~nban khoangcach (semi distance (qualitative». Clingchuydingvdim6ix,y, ZE U chungtaco d) 18( x,x)1=0; e) 18(x,y)I=18(y,x)1 f) 18( x,z)1::;;18( x,y)1+ 18( y,z) 1 D€ tinhtoanD-rutgQncuacacdi~uki~ncuathuQctinhC, chungtasedin chinhsU'ad6ichutmatr~nphanbi~tgQilamatr~n(C,D),maduQcchonhusau: 8 ( x,y)={a E C : a(x)*-a(y)va w(x,y) }, (2.16) Trongdo: W(x,y)E POSe (D) vay ~POSe (D) hoi;icla 1 2 3 4 5 6 1 2 C 3 C 0 4 C,S C,S C,S 5 C,S,P S,P S,P C,S 6 S,P C,S,P C,S,P C,P C 32 x !l POSe(D)vaY E POSe(D) ho~cla X,y E POSe (D) va x,y !l ID (2.17) vC1imQi X,Y E U NSuph~ndinhnghlabdiD la xacdinhbdi C, thldi~uki~nw(x,y)trong dinhnghlabelltrencoth€ giamthi€u thanhX,Y!l ID.Dodo8( x,y)la t~pcuata-t cathuQctinhmanophanbi~tcacd6itu'<;fngx vay makhongthuQcv~clingWp tu'dngdu'dngcuaquailh~ID. Ma tr~n(C,D)chobang2.1vC1icacthuQctinhdi~uki~nC,S,PvathuQCtinh quyStdinhnUtladu'<;fcchotrongbang2.5. Bang2.5:matr~n(C,D)chobang2.1 T~ph<;fpC' c ClaD-nit gQntrongC, nSuC' la t~pt6i thi€u cuaC saocho: C' n c :;t:0vC1imQic khacr6ng (c :;t:0)cuamatr~nphanbi~t(C,D). 1 2 3 4 5 6 1 2 C 3 - 0 4 C,S C,S C,S 5 C,S,P - S,P C,S 6 - C,S,P - C,P C 33 Do D6 D-rutgQnla t~pcon nhonha'tcuacacthuQctinhman6phanbi~t ta'tca cac lOptu'dngdu'dngcuamO'iquanh~ID phanbi~tbdi toanbQt~pcua thuQctinh.M6i mQtmatr~n(C,D)phanbi~tduynhfftxacdinh mQthamphan bi~tman6dinhnghlanhu'sau: Chungtahaygallm6ithuQCtinhamQtbi€n nhiphan,a,vaxet I8 (x,y) kyhi~ut6ngbooleancuata'tcacacbi€n booleandu'Qcgallchot~phQpcacthuQc tinh8(x,y). saud6hamphanbi~tc6th~du'Qcdinhnghlabdicongthuc: ID(C) = TI (I 8(x,y)): (x,y) E u2va8(x,y)*-0 (X,Y)EU2 (2.18) ThuQctinhsaudaythi€t l~pmO'iquanh~giii'ahlnhthucphanbi~tblnh thu'ongcuahamfD(C)vata'tcacacD-rutgQncuaC Tfftcanhii'ngy€u to'trongd~ngblnhthu'ongphanbi~tcuahamfD(C)la ta't cacacD-rUtgQncuaC N6i cachkhac,mQt~pconnhonha'tcuatfftcacacthuQctinhmaphanbi~t ta'tcacacdO'itu'Qngcoth~phanbi~tbditoanbQt~pthuQctinh. Hamphanbi~t(C,D)chomatr~nphanbi~t(C,D)chiratrongbang2.5la nhu'sau: fD(C) =C. (C+S).(C+S+P).(C+S) .(C+S+P).(C+S).(S+P).C =C. ( S+P) (2.19) 34 Trongdo"+" va"." Ky hi~uphepcQngvanhanBoolean,riengbi~t.Bdi VI, d,;mgblnhthuongphanbi~tcuahamla: fD(C) =c.s+c.p (2.20) ChungtacohaiD-rUtgQn,(C,S)va(C,P),cuat~phQpthuQcHnhdi~uki~n (C,S,P).chungtadIng nh~nxetdingD-corela t~phQpcuaUltcaph~nturieng recuamatr~nphanbi~t,nghlala: CORED(C)=(a E C :8(x,y) ={a},voimQix,y}. (2.21) Voi nhungbangqualOn,phuongphapd~fightv~HnhroanrutgQnkhong hi~uquaduvacacphuongphaptinhvi duQcsudl,mg. 2.9.DO DO CHAT Lu'(1NGTHUOC TINH Khi quailtamde'nslfgiamthiSuthuQcHnh,chungkhongthSco slfquail trQngnhunhau,vavai cai cuachungco thSloc;tibo rakhoimQtbangthongtin makhongma'tmatthongtinchilabelltrongbang.Y tudnggiamthiSuthuQcHnh cothSphatsinhbdivi~cgioithi~umQtkhaini~mladf)dochiltlli(Jngthuf)ctinh, dodocothSchophepchungtadaubgiacacthuQcHnhchibdihaimilcgiatrj,la cdnthiefhoi;tckh6ngcdnthief,nhungbdivi~cgallchomQtthuQcHnhmQtcons6 thlfctrongkhoang[0,1],nothShi~nslfquailtrQngnhuthe'naocuamQtthuQcHnh trongmQtbangthongtin. 35 DQdocha'th1QngthuQctinhco th~daubgiabdivi~cdolu'onganhhu'dng cuavi~cloc;timQtthuQctinhtitmQtbangthongtin trenvi~cxacdinhphanbi~t b~ngbang.XetC vaD Iat~phQpcacthuQcHnhdi€u ki~nvaquy€tdinh,rieng bi~t,xeta la mQthuQctinhdi€u ki~n.Nhu'dachIratru'ocday,cons6 y(C,D) th~hi~nmilcdQcuaslfph\}thuQcgifi'athuQctinhC vaD. Chungtaco th~bi€t h~s6Y(C,D)thayd6inhu'th€ naokhi loc;tibi)thuQctinha nghlaIa slfkhacbi~t Ia nhu'th€ naogifi'ay (C,D)vay (C - {a},D).tieuchuffnhoaslfkhacbi~tvaxac dinhmilcdQdangk~cuathuQctinhanhu'la: (J"CD(a) =(y(c,D)- y(C - {a},D)) =1- y(C - {a},D) ,. y(C,D) y(C,D) (2.22) Va ky hi~ub~nga (a)~1.thuQctinhquailtrc;mghonathlldn honcons6 a(a)co.Thi d\},cacthuQctinhdi€u ki~ntrongbang2.1chungtacok€t quasau: cr(C)=0.75 cr(S)=0.00 cr(C)=0.00 Bdi VImilcdQquailtn.mgcuathuQctinhS vaP la zero,loc;tibi)mQttrong chungra khi)ithuQctinhdi€u ki~nkhonganhhu'dngd€n slfph\}thuQc.Do do, thuQctinhC Ia dangk~nha'trongbang,loc;tibi)C, 75%( baphantIT)cacdu'ong 6ngkhongth~phanbi~trarangdu'Qc. D§u sao,d~giamthi~ubangdfi'li~u,trongbang2,chungtaco cr(C) =1 cr (S)=0.25 36 TrongtrtionghQpnay,giaffithi€u thuQctinhS d€ rut gQn,nghlala, sa d\mgchIthuQctinhC, 25%(mQtphffntti)cuacacd6ittiQngcoth€ dtiQcphanbi<$t ro rang,trongkhi bo thuQctinhC, nghlala sad\lngchI thuQCtinhS, 100%(ta't cii) cacd6ittiQngkh6ngth€ dtiQcphanbi<$trorang,conghlala trongtrtionghQp nayra ffiQtquye'tdinhla hoantoankh6ngth€, ngtiQcl~ib~ngvi<$cchIsad\lng thuQCtinhC, vaiquye'tdinhcoth€ dtiQcth\fchi<$n. Do doh<$sO'cr(a) coth€ hi€u nhtila ffiQt16ixayrakhi thuQctinhabi boo H<$s6ffiucdQdangk€ coth€ dtiQchi€u la ffiQt~pcacthuQctinhnhtisail: CYCD(B)=(y(C,D)- y(C - B,D)) =1- y(C - B,D) , y(C,D) y(C,D) (2.23) Ky hi<$ubdicr (B),ne'uC vaD diidtiQCbie't,B la ffiQt~pconcuaC. Ne'uB la rutgQncuaC, thla (B) =1,nghlala,boba'tky rutgQnnaokhoi t~phQpcuacaclu~tquye'tdinhlamchokh6ngth€ codtiQcquye'tdinhvdiffiQts\f chilcchiln: Ba'tky t~pconB naocuaC sedtiQcgQila mQtrutgQnxa'pXl cuaC, va consO' 8CD(B)= (y(C,D)-y(C-B,D)) -1- y(C-B,D), y(C,D) y(C,D) (2.24) 37 E(B) sedu'QcgQila mQtZ6icuasl!x{{pxl gt1ndung.No thShic$nchinhxac lamthe'naot~phQpcacthuQctinhB xffpXl t~phQpcacthuQctinhdieukic$nC. hiSn nhien,E(B)=1- cr(B)vaE(B)=1- E(C+B).bfftky t~phQpcon B naocuaC chungtacoE(B)::;E(C),ne'uB la mQthu nhecuaC, thlE(B)=o.Thidl;l,thuQc tinhS ho~cC cothSbie'tnhu'larutgQnxffpXlcua(C,S),va E(C)= 1.00 nhu'ngtfftca t~phQpcuathuQctinhdieukic$n(C,S,P)chungtaclingco giamthiSuxffpXlnnhu'sau: E(S,P) =0.75 Khai nic$mcuamQts1!rfftgQnxffpxlla phatsinhcuakhainic$mvemQts1! rutgQndffquailtamtru'dcday.MQtt~phQpB nhenhfftcuacacthuQctinhdieu kic$nC, saDchoy(C,D)=y(B,D)ho~cE (c,D)(B) =0 la mQtrutgQntrongchieu hu'dngtru'dcday. Y tu'dngve mQts1!rut gQngffn dung co thS hUll dl;lngtrong tru'onghQpkhi mQtcons6nhehancuacacthuQctinhdieukic$nco ichhantinh chinhxaccuas1!phanbic$t. 2.10.CACQUY LU! T QUYET DJNH vA s1jPHT)THUQC Vdi m6i s1!phl;lthuQc,C ~ k D chungtacothSlienh~vdimQt~pcacquy lu~tquye'tdinh,s1!matacacquylu~tquye'tdinhla nendu'Qcth1!chic$nkhidieu ki~nchinhxacla rhea.Noi cachkhac,m6imQtbangquye'tdinhxacdinhmQtt~p caccangthuccod(~lllg: " ne'u...thl ..." Thi dl;l,bang2.1xacdinht~pcaclu~tquye'tdinhsauday: 1. ne'u(C,Cao)va(S,Cao)va(P,Thffp)thl(Nut,Co), 38 2. ne'u(C,TB ) va(S,Cao)va(P,Tha'p)thi(Nlit,Khong), 3. ne'u(C,TB ) va(S,Cao)va(P,Tha'p)thi(Nlit,Co), 4. ne'u(C,Tha'p) va(S,Tha'p) va(P,Tha'p)thi(Nut,Khong), 5. ne'u(C,TB ) va(S,Tha'p) va(P,Cao)thi(Nut,Khong), 6. ne'u(C,Cao)va(S,Tha'p) va(P,Cao)thi(Nut,Co). Tli mQtquaildiemvelogic,caclu~tquye'tdinhIa lienh~m~thie'tli cac congthucph~ntli'cuad~ng(tenthuQctinh,gia tfi thuQctinh) va ke'thQpvdi nhaubdi "va ""ho~c ", va "sl)'suyfa "theo cachthongthuong. MQtlu~tquye'tdinhla chinhxac (chclchcln,baadam)ne'ucacdieuki~n cuanoxacdinhduynha'tcacquye'tdinh;ngoaifa lu~tquye'tdinhlakhongchinh xac(khongchclcchcln,khongco the).Trangthi dl,lbell tfen,lu~t1,4,5va 6 la chinhxac,ngoaifa lu~t2 va3 la khongchinhxac.HiennhienchIconhii'nglu~t chinhxacxacdinhcacquye'tdinhkhongmdh6. Bdi vi caclu~tquye'tdinhla caccongthuclogic,chungco theduQCddn gianhoab~ngcacsli'dl,lngcacphudngphaplogicthongthuongmakhongtrinh bayd day.Ngoaifa chungcotheclingduQcddngianhoasli'dl,lngphudngphap t~phQptho.thi dl,l,khaini~mve sl)'giamthieudfinde'nlo~ib6 cacdieuki~n khongdn thie't.Do do,ngoai bang2.1chungtaco thesli'dl,lngbang2.2ho~c 2.3decoduQccacquylu~tquye'tdinh. Tli bang2.2chungtaco: 1. ne'u(C,Cao)va(S,Cao)thi(Nlit,Co), 2. ne'u(C,TB ) va(S,Cao)thi(Nut,Khong), 39 3. ne'u(C,TB ) va(S,Cao)thl(NLi't,Co), 4. ne'u(C,Th!p) va(S,Th!p) thl(Nut,Khong), 5. ne'u(C,TB ) va(S,Th!p) thl(Nut,Khong), 6. ne'u(C,Cao)va(S,Th!p) thl(Nut,Co). Va tU'bang2.3chungtaco: 7. ne'u(C,Cao)va(P,Th!p)thl(Nut,Co), 8. ne'u(C,TB) va(P,Th!p)thl(Nut,Khong), 9. ne'u(C,TB) va(P,Th!p)thl(Nut,Co), 1O.ne'u(C,Th!p) va(P,Th!p)thl(Nut,Khong), 11.ne'u(C,TB) va(P,Cao)thl(Nut,Khong), 12.ne'u(C,Cao)va(P,Cao)thl(Nut,Co). Sa d1.;mgkY'thu~tlo~ibogiathuye'tkhongdn thie'tronglu~ttrlnhbayd phftnke'tie'p,cacquylu~tquye'tdinhcoth€ duQcddngianhoahdnnlla, Bang2.2.RutgQncuabang2.1 X6t lu~t1."neu(C,Cao)va(S,Cao)thl(Nlit,Co)"vabang2.2 Duong6ng C S Nut 1 Cao Cao Co 2 TB Cao Khong 3 TB Cao Co 4 Th!p Th!p Khong 5 TB Th!p Khong 6 Cao Th!p Co 40 Ta mu6nb6 (C,Cao),dSc6 "(S,Cao)thl(Nut,C6)",diSud6la kh6ngthS, VI duang6ng I va 3 thl dungla "(S,Cao)thl (Nut,C6)",nhungduang6ng2 "(S,Cao)thl(Nut,Kh6ng)" Ta mu6nb6(S,Cao),dSc6"(C,Cao)thl(Nut,C6)",diSud6la c6thSdu<;5c, bdiVIchIc62 duang6ng1va6 th6a"(C,Cao)thl(Nut,C6)",ngoairakh6ngc6 truangh<;5pnaomatithuftnnghlala kh6ngc6 truangh<;5pnaoma "(C,Cao)ma (Nut,Kh6ng)"ca X6t lu~t4. "ne'u(C,Thffp) va(s,Thffp) thl(Nut,Kh6ng) " vabang2.2 Ta mu6nb6(C,Thffp),dSc6"(S,Thffp)thl(Nut,Kh6ng)",diSud6la kh6ng thS,VIduang6ng4 va 5 thldungla "(S,Thffp)thl (Nut,Kh6ng)",nhungduang 6ng6 "(S,Thffp)thl(Nut,C6)" Ta mu6nb6(S,Thffp),dSc6 "(C,Thffp)thl (Nli't,Thffp)",diSud6la c6thS dU<;5c,bdiVI duang6ng4 c6(c,Thffp)va c6 "(Nut,Kh6ng)",ngoairakh6ngc6 truangh<;5pnaomatithuftnnghlala kh6ngc6truangh<;5pnaoma "(C,Thffp)ma (Nut,C6)" ca X6t lu~t5."ne'u(C,TB ) va(S,Thffp) thl(Nut,Kh6ng) " vabang2.2 Ta mu6nb6 (C,TB),dSc6 "(S,Thffp)thl (Nut,Kh6ng)",diSud6la kh6ng thSnhudilchungminhtren Ta mu6nbo (S,Thffp),dSc6 "(C,TB) thl (Nli't'Kh6ng)",diSud6la kh6ng thS,VIduang6ng2 va 5 thldungla "(C,TB)thl(Nut,Kh6ng)",nhungduang6ng 3 "(C,TB)thl(Nut,C6)" T6ml<;tid6ivdilu~t"ne'u(C,TB ) va(s,Thffp) thl(Nut,Kh6ng) " vabang 2.2,kh6ngc6giathie'tnaolakh6ngdn thie't. 41 Xet lu~t"6.ne'u(C,Cao)va(S,Thilp)thl(Nut,C6)".vabang2.2, Ta mu6nbo (C,Cao),d€ c6 "(SThilp)thl (Nut,C6)",di€u d6la khangth€, VIdlidng6ng4 va 5 thldungla "(S,Thilp)thl(Nut,Khang)",nhlingdlidng6ng6 "(S,Thilp)thl(Nut,C6)" Ta mu6nbo (S,Thilp),d€ c6 "(C,Cao)thl (Nut,C6)",di€u d6 la c6 th€ dli<jc,bdiVI dlidng6ngI va6 thoa" (C,Cao)thl (Nut,C6)",ngoairakhangc6 trlidngh<jpnaomallthu§.nnghlala khangc6 tru'dngh<jpnaoma "(C,Cao)ma (Nut,Khang)"ca T6ml<;li,sailkhi lli<jcbogiathie'tkhangdn thie'tcuacaelu~t1,2,3,4,5,6,tac6: 1. ne'u(C,Cao)thl(Nut,C6), 2. ne'u(C,TB ) va(S,Cao)thl(Nli't,Khang), 3. ne'u(C,TB ) va(S,Cao)thl(Nli't,C6), 4. ne'u(C,Thilp) thl(Nut,Khang), 5. ne'u(C,TB ) va(s,Thilp) thl(Nut,Khang), 6. ne'u(C,Cao)va(S,Thilp) thl(Nut,C6). D€ th€ hi~ntlnhchinhxacmOtquye'tdinhmatabdilu~tquye'tdinhchung tadn th€ hi~nb~ngmOtconso'cualu~t,chIrar~ngsl!mdrOngnaocualu~tla khangth€ tinc~y.D€ thl!c hi~nnochungtadinhnghlamOtIInhvl!cchilechiln cualu~t. Xet <Dva \{'la caecangthuclogicth€ hi~ncaedi€u ki~nva caequye't dinh,riengre,vaxet <D-7 \{'lamOtlu~tquye'tdinh,trongdo<Dsla ky hi~ucua 42 tronght$th6ngS, nghIa1at~phQpcuatfttca cac d6i tuQngthoatfongS dinh nghIatheoeachthongthuong Voi m6i 1u~tquye'tdinh -7 'P, chungta lien ht$mQtcon so'gQi1alInh vlfc cha:ccha:ncua1u~t,va dinhnghIanhusau: ,u«1>,\f) = I<Psn \fs I Is I (2.25) DI nhien,0 S J.l(,'P)s 1,ne'u1u~t-7 'P 1achinhxacthl J.l(,'P)=1 vacac1u~tkhongchinhxacthlJ.l(,'P)<1 Thi d\!,lInhvlfcchinhxaccuacac1u~tquye'tdinhdil quailtamtfUOCday 1anhusau: J.l«1>],'P])=1, J.l( 4,'P4)= 1, J.l( s,'Ps)= 1,J.l( 2,'P 2) = Y2, J.l( 3,'P3) = Y2, J.l( 6,'P 6) = 1 (2.26) trongdoi,'Pi kyhit$ucacdi@ukit$nvacacquye'tdinhcua1u~ti Chuy dinglInhvlfccha:cha:ncoth~duQcxemnhu1amQt slfphatsinh cuahamthanhvientheo1ythuye'tt~pthovaco th~duQchi~unhu1amQtkha nangcotinhchftt1adi@ukit$nmamQtd6ituQngx thoacacquye'tdinhclingcftp no thoacacdi@ukit$ncua1u~t.Thlfcslfthl,cac1u~tquye'tdinhcoduQctu mQt bangdli 1it$u1acac1u~tsuyfa cotlnhchfttlogicmanochophepkhamphacac m~uin giftutrongdli lit$u,vaco th~duQcsad\!ngtrongcacthao1u~nd~tlm chan1y,ho~cnhu1amQtdi~mba:td~uchovit$cthlfCthicacht$th6ngquye'tdinh b~ngmaytlnh,cacht$chuyengia,cacthu~toandi@ukhi~n,... 43 Do do, vdi m6i lu~tquy~tdinh-7\fIcoth~lienquailmQtlu~tsuylu~n theot~pth6gQila cacroughmodusponens n«t»;,u«t>,\f') n(\f') (2.27) trangdo1"[«1»=Isl/IVI va 1"[(\fI)=1"[(~I\\fI)+ 1"[«I».Il«I>,\fI). Lu~tnaychophepchungtatinhloanxacsua'tcuaquy~tdinhtrangdieu ki~ncuaxacsua'tcuacacdieuki~nvaxacsua'tdieuki~ncualu~tquy~tdinh. Thi dt,l,d~dangd~tinhloanr~ngn~u=(C, TB), (S,cao),(P,tha'p)va\fI =(nut,co),thlchungtaco 1"[«I» =1/3, Il( ,\fI)=Y2va 1"[(\fI)=1/3;d6ivdi =(C, cao)va \fI=(nUt,co), thl chungta co 1"[«I» = 1/3, Il( ,\fI)= 1va 1"[(\fI) = 1/3,nguqcl'.livdi = (S, tha'p)va \fI=(nUt,co), thl chungtaco 1"[«I» = 1/2, Il( ,\fI) = 1/6 va 1"[(\fI) = lA. Va'nde quailtamd trenla mQtphgncuacali hoi IOnhondii theodu6i nhieunamtrongtri tu~nhant'.lO(AI) va lien quaild~ncacphuongphapsuy lu~nhqpIy chung.Tranglogicc6di~n,cacIu~tcobancuaphgnk~tlu~nIacan cu trengia thi~tr~ngn~uva -7\f' ladung,thlphgnk~tlu~n\fI phaidung. Lu~tsuylu~nduqcbi~tnhu la moduspOllens.Dgusao,trongcaephuongphap suylu~nhqply chungchungtaphaithuanh~ndingphgnlien de vaphgnk~t Iu~nIa thuongkh6ngduqcbi~tmQtcachchilcchiln,mathuongIa vdivaiphgn suydoan,vadodophgnk~tlu~nclingphaiduqctrangbi vdi mQtst;(doIuong xacsua'thkhhqp.Logicc6di~nkh6ngclingca'pcacphuongphapd~giaiquy~t th~ti~nthoaiIuongnailnayvacachcualogicc6di~nla kh6ngcogiatri trong truonghqpnay.Do do,moduspOllenskh6ngth~duqcdoi hoinhuia mQtquy lu~thqply cobanchost;(suylu~nhqpIy chung. 44 Nhi€u mohlnhtinhroandangduqcd€ nghid~giaiquye'tva'nd€ nayvad~ di€u khiSntinhkhongch~cch~ncuano trongsl!hqply. Phudngphapt~ptho duqcgidi thi~ucove la mQtdiu traWira'tla tl!nhienchova'nd€ nayvanoco mQtsl!giaithichra'tla cdhtl'utrongcact~pdfi'li~u. 2.ll.PHUONG PHA.P LU!.N UNG DTjNG Ly thuye'tt~phqpthoduqcxemnhula mQtphudngphaptinhroanmdid~kham phanhfi'ngmohlnhtrongdfi'li~unghlala chungtaduqcchomQtt~pdfi'li~unhu la ke'tquacuasl!rhead5icachi~ntuqngtl!nnhienvaxii hQidC5ithl!Cva cong vi~cd~utiencuachungtala tlmnhfi'ngmohlnh~ngia'utrongdfi'li~u.Cacmo hlnhthuC5ngla trlnhbaydudid<;lngmQtt~pcacquylu~tquye'tdinh.Cacquylu~t cothSduqcsU'd\lngdSgiaithichdfi'li~u,nghlala,giaithichhi~ntuqngtl!nhien xii hQiho~cla cactie'ntrlnh n~md belldudidfi'li~u cuavaim6iquailh~"gay rahi~uqua".Thi d\lv€ khanangchilldl!ngki~mtracuacacduC5ng6ngducb~ng s~tduqcchotrongph~ngidi thi~u,la mQtthid\lminhhQara'tt6tcualo<;liling d\lngnay. D~usao,co ra'tnhi€u khanangkhacv€ lingd\lngcualy thuye't~phqp tho.Ngoai vi~cphanrichdfi'li~u,sl!chuY d~cbi~tcuacovelaphudngphapt~p hqpthoxU'ly cacd~cdiSm,maseduqcthaolu~nsdqua,b~ngmQtthid\l ddn giancuamQtsl!di€u khiSntinhi~ugiaothongphantan. 45 Xet rnQtgiaoIQra'tdongiand tronghlnh( giaonhautheoki~uchil'T) chIra d hlnh2.6. b @ +- II ............................ -.. .......................... -.. Carn ling Hinh2.6:rnQtgiaoIQdongian Chungtoi rnongrnu6nthie'tke'rnQthu~toandi~ukhi~nphantanIDase di~uhanhgiaothongdin cli trendi~uki~nt~ich6.ChungWi gia sadingcae di~uki~nlaxacdinhbdicacearnbie'nd~trenIanxevachIrahuangqu~ornong rnu6ncuarnQtchie'cxekhi de'ng~ngiaoIQ.VI rnvcdfchdongianchungWibo quanhi~ulInhvtfequailtrQngdn thie'trongvi~cdi~ukhi~nthtfcte'vagiasa dingcacd~cdi~rneuastfdi~ukhi~nco th~eha'pthu~nduQetrongtlnhhu6ng duQcrhotrongbang6duaiday,trongdo 46 O-do l-xanh 2-miiitenxanh(retnii) Nh~nxetr~ngbang2.6la khongphailake'tquacuaSvquailsatnhu'ngla mQt d~cdi~mcuacacyell du cholingxii' cuah~th6ngriengbi~td~cbi~t (nghlala Svdi~ukhi~n,chuongtrlnh,..) Sii'dl;mgphuongphapchiratru'ocdaychungtacobangcacquylu~tdi~u khi~nnhusau: ./ ne'u(b,O)ho~c(b,2)thl (a,O), ./ ne'u(b,l) thl (a,l), ./ ne'u(c,2) thl (b,O), ./ ne'u(a,O)thl (c,O)thl(b,2), ./ ne'u(b,l) ho~c(b,2)thl (c,O), ./ ne'u(b,O)thl (c,2), M<;tchchuy~nm<;tchtu'ongling cho t~pcua lu~tdi~ukhi~ndU<;1chi ra tronghlnh2.7.f)i~ukhi~ntuonglingdU<;1cve a hlnh 2.8 47 Bang2.6.mota caeyelleftuehoh~th6ngrieng bi~td~ebi~teuav~caeeachungxii ~. ., .&;1[n.~o Hinh2.7.m~ehehuy~nm~ehehot~pcaelu~tdi~ukhi~n a b e 1 1 1 0 2 0 2 0 3 0 0 2 48 t~ "[ n , ~ __d. r ok ! - v \ 1J --~_o :---\ -, 1-1~ /';".Lr':'n.-./ [2] ( 1( ~ /,-r-4 D Cambie'n 0 Dauhi~u Hinh2.8.Cantra1ercha t~pcac1u~tdi~ukhi~n Trangthid\l bell trenchungta chI r6 vi~csli'd\lng phuongti~ncuaky thu~tt~pthod~xli'19vai 1a(;licuatie'ntdnhd6ngthai.Chinh lOpnay cuacactie'n tdnh th~ hi~nmQtvai troratquail trQngtrangnhi~ulInh v1,1'c,d~cbi~t,trangmoi truangcongnghi~p,vakhongcon nghingaglnua,mohlnhthanhcongnhatclia cactie'ntdnhhi~nhanh1am(;lngPetri.Phuongphap1u~nt~phQpthoclingcoth~ hUlld\lngtrangvi~cchIr6v~cactie'ntdnhd6ngthai vat6nghQpcach~th6ng di~ukhi~nphlict<;1p,nhunglInhv1,1'cnaycualingd\lngyellcftunhi~unghiencUu hall.Vai ke'tquatranglInhv1,1'cnaycoth~tlmtrangnhi~utai1i~unghiencUu. 49 2.12.KETLU!N Phuongphapt~ph<;1pthod~phantichdli li~uconhi~ul<;1ithe'quantrQng.Vai l<;1ithe'du<;1cchiraduoiday: ./ clingca'pthu~toanhi~uquachovi~ctimkie'mcacquylu~t§'ngia'utrong dli li~u; ./ choranhlingdli li~uv~cacha'tlu<;1ngvas61u<;1ng; ./ timt~pnhonha'tcuadlili~uCsvgiamthi~udli li~u); ./ danhgiatinhdangk~cuadli li~u; ./ phatsinhrat~pcaclu~tquye'tdinhtUdli li~u; ./ d€ hi~u ./ clingca'pSvgiaithichd€ hi~uv~cacke'tquagianhdu<;1c; ./ nhi~uthu~toandin Cllly thuye'tt~ph<;1pthola di;icbi~tthichh<;1pchocac tie'ntrlnhxii'ly songsong,nhungd~khamphadi;icdi~mnaymQtcachd~y du,mQt6ChllCtinhtoandin Clltrenly thuye'tt~ph<;1ptholadn thie't. Ly thuye'tt~ph<;1pthoconhi~uthanhtlfu,tuythe',nhi~uva'nd~thvchanh va ly thuye'tdn themsvchliy. Bi;icbi~tla svphattri~ncacph~nm~mhi~uqua co anhhuangrQngrai trongvi~cphantichdli li~udin Clltrent~ph<;1ptho, cho cact~ph<;1pdli li~utoIon. Mi;icdil diiconhi~uphuongphapcogiatri v~tinhhi~uqua,t6iu'u,them nhi~unghienCUuv§:nla dn thie't,di;icbi~tkhi cacthuQctinhco gia tri la s6 lu<;1ngdu<;1cquantam.Trangb6icanhdocacphuongphapmoiphilh<;1pchocac giatri cuathuQctinhs6lU<;1nglaclingra'tdn thie't.NghienCUumarQngv~ma't 50 matdfi'li~uclingrfitquailtrQng.MQtslfsosanhvdi cacphuongphaptuongtlf khacv~ncondn du<;5cquailtam,m~cdli, dii co cacke'tquaquailtrQnggianh du<;5ctrong11nhvlfcnay.C~ncoslfquailtamd~cbi~ttrongvi~cnghiencUum6i quailh~gifi'am<;lngth~nkinhvaphuongphapt~ph<;5pthod~ruttrichdfi'lic$u. Cu6icling,cacmaytinht~ph<;5pthoclingrfitdn thie'tnhi~ulingdt,mgtien tie'n.Vai nghienCUutrong11nhvlfcnayla dangdu<;5ctie'nhanh.