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TM HIU V ANALYTIC HIERACHY PROCESS THNG QUA MINH HATrong i sng chng ta , i lc tht kh khn quyt nh mt vic no . Trong pht trin mt phn mm, tht kh khn chn mt kin trc phn mm no thch hp m da vo nhng thuc tnh v cht lng. i lc ta phi quyt nh da vo kinh nghim t chnh mnh hay ca ngi khc. V l do ny, cho vic lm mt quyt nh theo mt phng php khoa hc hn , mt k thut lm quyt nh c gii thiu , l AHP (Analytic Hierachy Process).
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Gii thiu v AHP :Hy xem v d sau :
y l s la chn ngi lnh o thch hp nht t cc ng c vin l Tom , Dick v Harry. Yu t xem xt l tui , kinh nghim, trnh v uy tn. Nu ta khng c mt phng php c th th vic la chn rt l kh khn. Nhng khi p dng k thut AHP vo, ta c c cc trng s u tin dnh cho cc ng vin . T y ta c th thy vic chn Dick l thch hp nht cho v tr lnh o. Tip theo l Tom v cui cng l Harry. Vy AHP l g ?
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mrbkiter AHP l mt k thut to quyt nh , n gip cung cp mt tng quan v th t sp xp ca nhng la chn thit k v nh vo n m ta tm c mt quyt nh cui cng hp l nht. AHP gip nhng ngi lm quyt nh tm thy ci g l hp l nht cho h v gip h vic hiu nhng vn ca mnh . Da vo ton hc v tm l hc , AHP c pht trin bi Saaty trong nm 1970 v c m rng v b sung cho n nay. AHP cung cp mt khung sn chnh xc cho cu trc mt vn cn gii quyt. AHP kt hp cht ch vi chun quyt nh v ngi lm quyt nh s dng phng php so snh theo cp (pairwise comparison) xc nh vic nh i qua li gia cc mc tiu.
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Qui trnh c bn ca AHP.
AHP c 3 phn on c bn : phn gii vn cn gii quyt , so snh s nh gi ca nhng phn t v tng hp u tin. Ta xem xt v d sau : Mt cng ty mun chn mt v tr m rng hot ng cng ty.Cng ty s dng AHP nhm xc nh v tr no thch hp xy dng nh my mi. Cng ty da vo 4 tiu ch :gi tr ti sn(Price) , khong cch gia cc nh cung cp (Distance) , cht lng lao ng(Labor) v chi ph lao ng (Wage). Cng ty c 3 v tr (location) A , B , C xem xt da vo 4 tiu ch trn.Ta s xem xt quy trnh ca AHP thng qua v d ny. 1. Phn gii vn cn gii quyt : AHP phn gii vn ra thnh cu trc cy phn cp . lm iu ny bn phi khm ph nhng kha cnh ca vn t tng qut n chi tit , biu din chng theo cy a nhnh . Phn t ti mc cao nht ca cy c gi l mc tiu (goal). Nhng phn t mc cui cng c gi l nhng s la chn (alternative). Ngoi ra cn mt nhm cc phn t lin quan n cc yu t hay tiu chun (criteria) lin kt gia nhng s la chn v mc tiu. Mt cy phn cp vi mc tiu nh , nhng s la chn l cc phn t l v cc phn t tiu chun thi gia. v d trn , ta s c 4 tiu ch l gi tr ti sn , khong cch gia cc nh cung cp,cht lng lao ng v chi ph lao ng. 3 s la chn l v tr A , B , C. y l cy phn cp AHP cho v d :
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V d v m hnh cy phn cp AHP.
2. So snh s nh gi ca nhng phn t. c th nh gi s quan trng ca mt phn t vi 1 phn t khc , ta cn mt mc thang o ch s quan trng hay mc vt tri ca mt phn t vi 1 phn t khc qua cc tiu chun hay tnh cht. V vy ngi ta a ra bng cc mc quan trng nh sau : Mc quan trng Quan trng nh nhau (Equal Importance) Quan trng bng nhau cho n va phi (weak or slight) Qun trong va phi (Moderate importance) Quan trng t va phi n hi quan trng hn (moderate pus) Hi quan trng hn (Strong importance) Hi quan trng cho n rt quan trng (strong plus) Rt quan trng (very strong importance) Rt quan trng cho n v cng quan trng(very , very Strong) V cng quan trng Gi tr s 1 2 3 4 5 6 7 8 9 c u tin mc cao nht c th Mt hot ng rt quan trng. Kinh nghim v s phn quyt c s u tin va phi cho mt hot ng. Kinh nghim v s phn quyt u tin mnh cho mt hot ng Gii thch 2 hot ng ng gp ngang nhau
Bng xp hng cc mc quan trng
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V d , nu mt phn t A quan trng hn phn t B v c nh gi mc 9 , khi B rt t quan trng vi A v c gi tr l 1 / 9. Bn cht ton hc ca AHP chnh l vic cu trc mt ma trn biu din mi lin kt ca cc gi tr ca tp phn t. Ma trn h tr rt cht ch cho vic tnh ton cc gi tr . ng vi mi phn t cha ta thit lp mt ma trn cho cc s so snh ca nhng phn t con ca n. v d trn , ta c 5 phn t c cc phn t con , l phn t mc tiu , gi c , khong cch , cht lng lo ng v chi ph lao ng . Ta thit lp cc ma trn cc ma trn cho tng phn t da vo bng xp hng cc mc quan trng nh sau: Gi c : Khong cch.
Cht lng lao ng :
Chi ph nhn cng :
Ngoi ra, ta c ma trn u tin cho cc tiu ch :
3. Tng hp u tin . Ta s dng nhng ma trn c c t bc 2 c th thit lp ra u tin (priority) ca cc phn t trong cy phn cp. u tin l mt s khng m chy t 0 n 1. Chng biu din s lin kt ca trng s trong tng phn t tng mc.Theo nh ngha, u tin ca mc tiu l 1. Tng u tin ca mt mc s l 1. v d trn , vi tng ma trn ta s ra c vecto v u tin cho cc nhn t trong ma trn .Ta s khng i vo chi tit ti sao li tnh ra c nh vy. Ma trn gi c : Vector u tin :
Ma trn khong cch :
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Ma trn cht lng lao ng :
Ma trn chi ph lao ng :
Ma trn u tin cho cc tiu ch .
Vector u tin ca cc tiu ch
T nhng vector u tin v gi c , v khong cch , cht lng lao ng v chi ph lao ng ta thit lp nn ma trn tiu ch nh sau :
Ta nhn ma trn u tin vi vector u tin ca cc tiu ch , khi s ra kt qu vector u tin ca cc la chn A , B , C.
By gi ta c y u tin ca cc phn t . Ta c cy phn cp c thit lp u tin trong v d trn nh sau :
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Cy phn cp c thit lp u tin
Nhn vo cy phn cp ta thy la chn v tr C l thch hp nht.
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Cc cng c lin quan n AHP .
AHP c th c chy bi s dng dng mt cng c dng bng tnh nh Excel.Ngoi ra cn c mt cng c c tnh h tr tt hn v trc quan hn l Expert Choice . y ta s xem xt Expert Choice version 11.5 . 1. Giao din Expert Choice version 11.5 . Khi bt u khi ng Expert Choice , giao din chng trnh hin ra nh sau :
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Trong hp thoi Welcome to Expert Choice , chn Create new model chn phng php l direct ri nhn OK . Lu m hnh vi 1 ci tn no . By gi ta xem xt cch s dng Expert Choice. 2. Cch s dng Expert Choice 11.5. Trong hp thoi Goal Description , ta nh vo l choose the best location ri nhn OK.
Bm vo Edit > Insert Child or Current Node , nhp vo Price , Distance , Labor v Wage.
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Ta c c mc u tin ca cy phn cp. Gi ta bt u so snh cc cp trong mc 1. Nhn mc Goal > Assessment > Pairwise . Ta chn tab 3:1 . Sau bt u nhp gi tr u tin mc 1 vo.
Ta ln lt nhp cc gi tr vo.
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Sau khi nhp xong cc gi tr , chn Assessment > Calculate hoc chn th Priorities devired from pairwise Comparisons . Mn hnh priority hin ra .
By gi ta nhp cc phng n. Bm Edit > Alternative . Nhp vo cc phng n A , B , C. Ta chn Go > DataGird.
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mrbkiter Nhp chn tng ct mc tiu , bm Formula Type > Direct . Nhp gi tr vo cc tiu ch ta ra c bng sau :
Nhn vo bng ta thy ct total. Ct ny ch ra chn C l thch hp nht . N trng vi kt lun ta lm tay trn.
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Kt lun.
Bi vit gii thiu s qua v AHP v cc qui trnh c bn khi p dng AHP to mt quyt nh. Sau gii thiu ngn cng c s dng AHP gip h tr to quyt nh. Bi vit tuy cn s si nhng s gip ngi c nm c nhng nim s khai v AHP cng nh cch s dng. Hin nay AHP ang c s dng rng ri v vn cn c tip tc pht trin.
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Tham kho.1. 2. 3. 4. 5. Wikipedia , http://en.wikipedia.org/wiki/Analytic_Hierarchy_Process . Hoang Pham, Software Reliability , USA. Geoff Coyle , The Analytic Hierarchy Process (AHP). Thmas L.Saaty , Decision making with the Analytic Hierarchy Process , USA. Liming Zhu , Tradeoff and Sensitivity Analysis in Software Architecture Evalution Using Analytic Hierarchy Process , Australia.
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