Nguyin Hiru Diing. Tap chi Phat tri6n Kinh te, 27(2), 17-34 17
Xay dyng cac chi so
do lirong mu'c song ho gia dinh Viet Nam
NGUYEN HCru DUNG
Truang Dai hpc Kinh te TP.HCM - nhdung(§ueh.edu.vn
Ngdy nhdn:
11/12/2015 Ngdy nhgn lgi:
21/02/2016 Ngdy duyet ddng:
22/02/2016 Ma so:
1215-I32-V04
Tie khda:
Chi so mirc song, phuang phap PCA, muc song hp gia dinh VN.
Keywords:
Living standard index, principle component analysis (PCA), Vietnam Household Living Standard.
Tom tat
Nghien ciiu nham xay dung chi so do luong miic song cua cac hp gia dinh "VN. Cac chi so nay dugc xay dyng theo phuang phap phan tich thanh phan chinh (PCA) tii cac so lieu ve tai san lau ben, cac dac diem va tien ich nha a cua hp dugc trich xuat tir bg du lieu Khao sat muc song hp gia dinh VN - 2012 (VHLSS-2012). Dp manh va kha nang ap dung cua cac chi so dugc kiem djnh bang he so tuang quan Pearson, the hien su nhat quan ben trong cua cac chi so Pearson so vai cac chi so theo thu nhap va chi tieu binh quan cua hp. Ket qua cho thay cac so lieu cua 'VHLSS-2012 co the dugc su dung de xay dyng cac chi so hQu ich va dang tin cay ve mirc song, ho trg tot trong viec danh gia chat lugng song va nang luc cua cac hg gia dinh "VN.
Abstract
This study aims to construct indices for measuring living standards of households, using principle component analysis (PCA) of data on assests and housing characteristics of households extracted from Vietnam Household Living Standard Survey 2012 (VHLSS-2012).
Their robustness and use are tested via Pearson correlation coefficients and found to be internal consistent, compared with those based on income and expenditure per capita. Among the three indices living standard index (LSI) shows better distribution relative to the other two. The findings conclude that simple household socioeconomic data, available in VHLSS surveys, can be adopted for compiling reliable indices of households' living standards, which can assist in the assessment of their capacities and quality of life.
18 Nguyen Hth. Dung. Tap chi Phat tri6n Kinh 16, 27(2), 17-34
1. Gidi thieu
Cic nghien ciru gin day vl tinh trang sire khoe, sue khoe sinh sin, cac vin dl nhan chiing hgc vi nhfl'ng can thiep ciia Cbfnb pbii trong viec cai thien mii'c song hg gia dinh cbo thiy cd su khie biet ding kl vl kit qui vi mdi quan tim ldn khi sir dyng cie phu(jng phip khac nhau tii' sd lieu kinh tl xa hgi. Mii'c do phiic tap trong do ludng miic sdng cac hg gia dinb la do khd khin trong viee xie dinh cich thiic do ludng hgp li va do tin cay.
Cic phuang phip dinb gii hien trang kinh tl xa hdi, mire sdng cua hg gia dinh co thj phan thanh hai nhdm; Nhdm thu nhat dya theo cich thiic do ludng bing tiln, va nhom khic dya theo each tilp can khdng dimg tiln. Cae nhi kinh t l truyin thdng thudng si:
dung cic phuong phip thudc nhdm thii nhat vi viee do ludng bing tien thudng dg dang, dan giin vi de hilu. Sd lieu vl thu nhip hoac chi tieu thudng dugc sir dung dl dai dien cho miic tigu dimg ciia hd (Atkinson, 1989). Tuy nhien, cd rit nhilu phg phan vl phtrong phap do ludng bing tiln. Mot trong nhu'ng dilm yeu cua phuang phip niy la so lieu ve tbu nbap va cbi tigu cd tinh chinb xie khdng eao trong cic cudc dieu tra. Do viy, trong nhirng nim gin diy, cic chi sd danh gii mii'c sdng cua hd gia dinh khdng sir dung tien da dugc phit triln dl phin loai, danh gii tinh trang kinh te xa hdi cua hd, vi dy nhu chi sl tai sin, chi so kinb tl xa hdi, chi so giau cd/thinh vugng (Filmer & Pritchett, 2001).
Cich tbiic cbinb dl xiy dyng cac chi so khdng su' dyng tien la dua vao phuong phap phin tich thanh phin cbinb (Principle Component Analysis-PCA). Phuang phap PCA da dugc nhilu tic gia xie nhin li phuong phap cd gia tri tjiyc tien cao trong viec xay dyng cic chi so do ludng sy khac biet vg hien trang kinh tg xa hgi eua nhdm hd gia dinh.
Cic cbi sd tai sin, tlnh trang kinb tg xa hdi bay mirc sdng la nhting cich thiic do ludng dugc ip dung rdng rai nhim xem xet tinh trang sire khoe, dinh duang, giio dye va nhiing cbi tigu khac vg su thinh vuo'ng trong xa hdi dya theo sd lieu ciia cac bd gia dinh. Theo Rutstein (2008), Ngan hing Thi gidi (World Bank-WB) da sir dyng cac chi so nay trong nhtrng khuygn cio vg chuang trinh, chfnh sich ciia td chiic. Gin day nhit, WB ciing i3a ap dyng chi sd nay dg xem xet tinh trang thinh vugng ciia 52 quoc gia dugc khao sat trong chuong trinh nhan chiing hgc va sue khoe. Dong thdi ehi sd nay ciing dugc sii dung cho cic myc dich khac nhau trong mdt sd chuong trinh ciia UNICEF, khio sat ve benh AIDS va sdt ret. Cic cuoc khio sit nhin chiing hgc va sii'c khoe (DHS) cung sir dyng phuang phip niy trong nhigu nghien ciru vl sy thinh vugng cua cic qudc gia.
Dgn nay, cich tigp can phi tiln te va phuang phap PCA dugc ip dyng rit nhieu tren thg gidi de xiy dung cac chi so. Vi thi, nghien ciiu dl li'ng dung tai VN, xem xet dac
Nguyin Him Dung. Tap chi Phat trien Kinh t6, 27(2), 17-34 19
dilm cua cic ehi sd, so sanh vdi cac chi bao truyin thdng trudc day la dieu cin thiet.
Muc tieu nghien ciiu nay nhim xiy dyng cic chi sd do ludng miic song cua cic hd gia dinh VN, va xem xet miic do tuomg thfch ciia cic chi so dugc xiy dyng vdi cac chi sd truygn thdng dugc do ludng bang tien.
Pham vi nghien ciiu bao gdm cic hd gia dinh trong toan qudc dugc khao sat trong bd so lieu khio sit miie song cac hg gia dinh nam 2012 (VHLSS-2012). Tong sd hg trong bg sd lieu ed cic thdng tin ve thu nhap, chi tieu, ca sd ha tang, tien fch cudc sdng, dac diem nha d, cac tai sin lau bgn ciia bd, va cic bign sd kinh tg-xa hdi khic gdm 9.399 hd.
Trong do, sd hg sau cimg dugc sir dung la 9.336, bao gdm tit c i cic 'vung dja If, khu vye thanh thi va ndng thdn.
2. Tong quan cff sd li thuyet va nghien ciiu lien quan 2.1. Cas&li thuyit
Ve mat If thuygt, sy thinh 'vugng hay giiu cd, muc sdng cao thip la mgt khai niem cd thg do ludng dugc. Khi do ludng sy thjnh vugng 'tuyet ddi', cic nha nghign ciiu thudng dua ra mgt danh sich tii sin (vit thg vi tign te), sau do quy ddi gii tri ciia chiing theo gii thi trudng, kbau hao chung va tinb toin gia tri cdn lai. Cic nhi nghign ciiu thyc hien cich phin tich tuang ty nhu hach toan cac khoin ng. Tuy nbien, cich lam nay cung gap pbii khd khin tuang ty chi tigu thu nhip vi chi tigu (Montgomery & cgng su, 2000).
Phuang phip luin tdng quit dg tfnh toan chi sd tai sin (DA), miic sdng (LSI), thinh vugng (WI), la cic chi sd xiy dyng theo phuang phip PCA duge trinh bay trong nghien Cliu cua Filmer va Pritchett (2001). Rutstein va Johnson (2004) md ta chi tigt each tfnh cac chi sd nay trong cic cudc khio sat ve nljSh chung hgc va siic khoe cua cac thanh vien trong hd gia dinh ddng thdi sap xep .cac hd tren mdt thang do lign tuc ve sy thinh vugng tucmg ddi, va chi sd dugc tao ra bing quy trinh phin tfch thdng ke PCA. Cic nghien cuu nay so sanh viec sir dyng eac chi sd tai sin vdi cic chi sd truyen thdng khic nhu chi tieu, va cho ket luin chi sd tai sin cd the dai dien tdt han cho tinh trang kinh tl ciia hg.
Theo Filmer va Scott (2012), trong phuang phap xiy dyng cac chi sd thi sd lieu cu thg ciia hd se quygt dinh viec sd hiiu mdi tai sin se ed mdt trgng so nhu thi nao trong chi sd chung, thdng qua viee chuyen ddi dan thuin ve mat toan hgc. Nhu vay, khdng gidng nhu trudng hgp eiia chi sd ngheo da chieu (MPI), trong eic chi sd hinh thanh theo phuang phap PCA hoic MCA, mdi tai sin tiiy thudc vao die tinh ciia nd se cd tie dgng
20 Nguyin Hilu Dung. Tap chi Phat triln Kinh tl, 27(2), 17-34
im hay duang din chi so chung. Cie chi so tii sin khdng gan miic trgng so bing nhau cho cae biln sd, vi nhu thi khdng dan giin la hinh thinh nen mgt biic tranh tong hgp ve miic song hay trgng sd bing nhau giiJa cic chilu nhu trudng hgp cua Multiple Correspondence Analysis (MPI). Nln tang li luan cua cic chi sd tai sin khdng dan thuan chi do ludng vin dl sd huu cic tii san ddng gdp vao sy thinh vugng ciia hg hoac phan inh tryc tilp thu nbap hay tieu diing cua hd, mi cic mau hinh sd hilu tii san giura cic ho cho phep nha nghign ciiu phin bd cic hd gia dinh vio mu'c sdng giau - ngheo khic nhau trong xa hgi. Cac cbi so tai sin thip dugc gii dinh li cd lign quan true tiep den miic song ciia hd trong dai ban thip. Miic sdng thap niy dugc phin anh thdng qua mau hinh sd huu tii sin gifl'a cic hd.
v l mat li thuylt, phuang phip PCA li mdt kT thuit thong ke da biln lign quan den phan tich nhin to, nhim giim bdt so lugng cie bien sd tir cic bien ban diu, nhung cac nhin td dugc chili xuit vin dai dien dugc cho die tfnh cua mau. PCA cd the xac dinh trgng sd ciia cac nhin td dai dien cho cic tai sin cua hg, tim kiem mgt su ket hgp tuyen tfnh giura cic bien. Theo Vyas va Kumaranayake (2006), nhirng tai sin nio phan bo khdng dong dgu giua cic hd trong mau se cd trgng sd cao hon trong thanh phin thii nhat.
Digm sd dugc tao ra tir thinh phin thii nhit dugc sir dung nhu la mdt chi bio ve miic sdng, tinh trang kinh te xa hdi cua hg. Cac diem nay sau dd se dugc dimg de phin ra cac ngfl phan vi theo tii sin, thanh tbi va ndng thdn dg xem xet mii'c thinh vugng cua cac hg.
De udc lugng cic trgng sd cua mdi bien trong thinh phin dugc chiet xuit tir PCA va cich tfnh khac, Howe va cdng sy (2008) sir dung nhieu cau triic khie nhau cua biln s6 de so sinh ket qui nhu; (1) Ap dung PCA cho tit ca cac nhdm biln chung loai (Categorical); (2) Ap dyng PCA nhung chi sii dyng phien ban nhi phin ciia cac biln chiing loai; (3) Su dung trgng sd bing nhau cho tit ca cac biln; (4) Tao trgng so cho cac bign nhi pbin bing each liy nghich dio ti le din sd sd huu tai sin dd; va (5) Ap dung MCA cho tit ci cac biln chiing loai. Kit qua nghien eiiu cho thay PCA va MCA td ra thich hgp ban va cbo chi sd kba tuang ty nhau so vdi hai phuang phap dan gian la trgng sd bang nhau va nghich dao ti le sd huu trong viec xiy dyng cic chi so. Tuy nhien, MCA khd thyc hien va khd hilu hon PCA do khdng thi sir dyng c i biln nhj phin va biln lien tuc. Tie gii nhan thiy PCA la cdng cu kba thfch hgp dl tao trgng so cho cac biln khi Xiy dyng chi so mirc sdng, thinh vugng.
Nguyin Hilu DOng. Tap chi Phat triln Kinh tl, 27(2), 17-34 21
2.2. Cdc nghiin cieu liin quan
Sahn v i Stifel (2003) sii dyng chi so dya vao tai sin thay cho cac nghien ciiu truyen thdng dya vao digu kien kinh tg v i chi sd niy dugc sir dung dg xep hang hd va hinh thanh ngn ngu phin vi sy thinh vugng. So sinh vdi cac thudc do dya vao sd lieu tieu dimg, dfl- lieu dugc ygu ciu de hinh thinh nen chi sd thinh vugng it ban va viec do ludng cflng dan giin hem. Chi sd thinh vugng dua trgn tai sin cung bao ham dugc tfnh da chieu cua ngheo khd m i bin thin su da chigu nay vdn dT khdng the hien dugc neu chi dya trgn tieu thy va thu nhap. Quan trgng ban, chi sd thinh vugng dya tren tii sin cdn dugc cho la thdng tin quan trgng giup du bao tdt nhit cic vin de ve dinh duang, ti le tre di hgc ban la chi tigu chi tigu.
Filmer va Pritchett (2001) vdi du lieu tir An Do, Indonesia, Nepal va Pakistan da so sanh cbi sd thinh vugng dya trgn tai sin vi dya tren tieu dung bang eich xem xet sy khie biet giua viec diing cbi tigu so vdi chi sd tai sin vi phin tfch tic dgng cua timg chi sd ddi vdi ket qui giio due trong du bio tinh trang nhip hgc. Ket qua cho thiy cd sy tuang quan rat manh giura chi sd thinh vugng vdi ning suit va sy ngheo khd.
Mgt sd nghign ciiu lien quan cung cho thiy each tiep can dya vao tii sin la hgp If khi xem xet eic tic ddng dgn kgt qui giio dye. McKenzie (2005) sir dung thanh phan thii nhit trich tir phuomg phip PCA dg nghign ciiu bit binh ding bing cic chi sd tii sin, tip trung vg vin dg di hgc ciia hgc sinh nam tai Mexico. Kgt qui eho thiy bit binh ding vg cic tien ich cgng ddng inh budng rd dgn viec den trudmg cua tre (Filmer & Scott, 2012).
Bollen va cgng sy (2002) xem xet kgt qua thyc nghiem cua nhigu chi sd dai dien cho tinh trang kinh te khdng cho rang cich do ludng bing tign Ii tdt nhit, thay vao dd la tap trung vao nghign ciiu cie chi sd dai dien cho tinh trang kinh tg da inh hudng the nao den cac bign sd khic ve sy sinh sin vi sire khoe cua phu nu tai cic nudc dang phit trign.
Wagstaff va Watanabe (2003) khi chgn lya cbi tieu tinh trang kinh te xa hdi de do ludng bit binh ding vg siic khoe tai 19 qudc gia cung ket luin chi sd dya vio tai sin cflng tdt nhu cbi sd dya theo tieu dung, vi khdng cd sy khic biet ldn gifl'a 2 nhdm chi sd. Kgt qui khang dinh miic do tin ciy cua phuomg phip sir dung chi sd tii sin.
Gunnsteinsson va edng sy (2010) sir dung chi sd kinh te-xa hgi, tai sin xiy dyng tir phuang phip PCA de do ludng miic sdng hg gia dinb ndng thdn tai 'viing phfa bic Bangladest. Hg phat hien ed sy nhat quin bgn trong cua cic chi sd vdi tinh trang thi chit
\'i siic khoe cua tre em. Ddng thdi tir cic thdng tin kinh tg-xa hdi dan gian cua cic hd gia dinh cd thg sir dung dg xiy dyng cac chi sd do ludng miic sdng cua hd.
22 Nguyin Hitu Dung. Tap chi Phat triln Kinh tl, 27(2), 17-34
3. Phu-oTig phap nghien Cliu 3.1. Cdc logi chisd
Dya theo If thuylt va kit qui cua cac nghien ciiu trade day, tic gia ap dyng phuong phip va khung phan tich cua Filmer va Pritchett (2001), Rutstein va Johnson (2004), McKenzie (2005), Gunnsteinsson va cdng su (2010) dl xay dyng 3 loai chi sd do la; Chi sd die dilm nhi d, chi sd tai sin lau bin va chi so mirc song dugc md ta trong Hinh 1.
Cac bien so ve nha a Chi s6 dac diSm nha 6 (DCI) Cac bien so ve tai san lau ben Chi s5 tai san lau ben (DAI)
Chi so miic song (LSI)
Hinh 1. Ciu true cic loai chi sd
Chi sd dai dien cho cic die dilm vi tien ich trong nhi ggi tat la chi sd die digm nha (DCI) gdm cic biln sd vl nha d nhu; Loai nhi, loai mii Igp nha, loai tudng, kigu nha ve sinh, ngudn nude sinh hoat, ngudn dien thip sing v.v..
Chi sd tii sin liu ben (DAI) bao gdm cie bign sd vg tai sin lau ben cd trong radi hg nhu; TV mau, din nhac, miy vi tfnh, tu lanh, xe miy, miy nude ndng, dien thoai di dgng, quat dien, d td, v.v..
Chi sd miic sdng (LSI) gdm cic bign sd cua 2 nhdm bien sd die diem nhi va dd dimg liu bgn.
Cic chi sd nay tfnh chung cho tit ca cie hd trong ci nudc, sau dd tach rieng ra cho vung thanh thi va ndng thdn, va gifla cic vung dia If.
3.2. Phuang phdp xdy dung cdc chi sd
Phuong phip dl xiy dyng chi so li phuomg phip phin tfch thanh phin chi'nh (PCA).
Ve nguyen tic trong phan tfch PCA cd bao nhigu biln so thi se eho ra bay nhigu thanh phin phdi hgp tit ca cac biln sd, vi cbi chgn cac thinh phan cd Eigenvalue ldn hon 1.
Tuy nhien, cbi cd thanh phin thu' nhit duge su dung dl tfnh dilm chi sd. Nghign ciiu cua Filmer vi Pritchett (2001) da thu' nghiem sur dyng thgm thanh phan chi'nh thii 2, nhung ket qui sau cung cho thay dilm ylu td cua moi biln trong 2 thinh phan gay nhilu khd khan trong viec giii thfch inh budng cua chiing len chi sd. Kit qui cua Houweling va cgng sy (2003), McKenzie (2005) cflng kit luan thanh phin diu tien mdi thfch hgp de dai dien cho viec do ludng muc sdng eiia hd gia dinh.
Nguyin HOu DDng. Tap chi Phat triln Kinh tl, 27(2), 17-34 23
Cic biln sd de dua vio phin tich PCA dlu li biln nhi phan (Binary Data). NghTa li hd gia dinh cd tai sin nao dd hay khdng, hoac cd tiep can tien fch dd hay khdng (Vf du:
ludi dien). Tat ca cic bien chiing loai va cic bien lien tuc, vf du nhu loai nha, sd lugmg xe miy dgu dugc ma hda thanh bien nhi phan. Cic bign dugc tao ra nhu: Nha kien cd nhan gia tri=l, cic loai khic=0; tuomg ty cic bign khac phii tao ra la nhi ngdi, nha mii li, nhi bin kign ed. Bign lign tuc nhu khdng cd xe miy nhan gii tri = 0, cd tir 1 xe miy trd len nhin gii tri = 1. Cic bign it xuit hien (ti le sd hilu tai sin dd qua thip) se dugc gdp lai trong chung loai lign kg. Cic bign cd tin suit xuit hien cao se dugc tieh rieng.
Mdt sd hg gia dinh cd bign sd khdng cd sd lieu (Missing Data) deu dugc tbay thg bang gii tri trang binb ciia bien sd dd (Gwatkin, 2000), vi neu loai bd qui nhieu miu digu tra (bd) cd the anb budng dgn kgt qui phin tfch v i sd lieu bi hdng niy thudng nam d cic nhdm cd tinh trang kinh te-xa hdi thip (Cortinovis & cdng sy, 1993).
3.3. Cdc bu&c phdn tich kit qud
Sau khi da thyc hien xong PCA, sii dyng nhin td li trgng sd cua cic bign trong thanh phin thii nhit de tao ra bien phy thugc li sy kgt hgp tuygn tfnh giua cic bign sd. Gii tri cua bien phy thudc la diem sd dai dien cho tinh trang kinh tg xa hdi eua mdi hd. Digm sd cang cao thi hg cing dugc xem la cd tinh trang kinh te tdt hom hoic miic sdng cao hom cic hg cd digm sd thip. Viec phan tich kgt qui se dugc thyc hien vdi cic ndi dung nhu sau;
Budc 1; Sir dung chi sd miic sdng (LSI) de phin bd cic hd gia dinh thanh cic nhdm kinb tg - xa hdi khie nhau. Trong nghign ciiu niy, tic gia ip dung cich phan chia 5 ngfl phan vi dai dien cho cic nhdm hd gia dinh tir ngheo nhit (nhdm 1) dgn giiu nhit (nhdm 5) nhu dugc ap dung trong nhigu nghien ciiu trudc diy.
Budc 2: Sir dung 5 ngfl phin vi dai dien cho miic sdng de phan tich kgt qui; Miic do chat che bgn trong cua chi sd, so sinh sy tuomg thich cua hg phin theo cbi sd miic sdng vdi ngu phan vi dugc chia theo thu nhap va chi tigu binb quin diu ngudi (nhin khiu)/thang.
Bude 3; Phan tfch va thio luin cic ehi sd phin theo thanh thi/ndng thdn va cic 'viing dia li.
3.4. Cdc sd lieu trich tie bd die liiu VHLSS 2012
Sd lieu sau khi trich Igc dugc kigm tra tinh trang phu bgp cua nd doi vdi yeu ciu phin tich, die biet la tinh trang thigu gii tri thdng tin trong miu kbio sit. Kit qui kilm tra
24 Nguyen HOu Dung. Tap chi PhM triln Kinh tl, 27(2), 17-34
cho thiy 63 miu khdng cd qui nhilu thdng tin cua eic biln nen bi loai ra. Sd mau sau ciing dugc su' dyng trong dl tai la 9.336 hd trgn pham vi ca nudc. Cic bien sd ve tii san liu bin, dac dilm nha d va tien fch dugc thi hien rd qua Bing 2.
4. Ket qua nghien ciiu
4.1. Dgc diem kinh te-xd hdi cua hd gia dinh
Bing 1 trinh biy miic thu nhip binh quan dau ngudi (nhin khiu) la mgt trong 2 chi tigu thudng su dung khi xem xet dinb gii ngheo ddi theo eich truygn thdng. Kgt qua cho thay miic trung binh ciia toan vung, cac vung vi khu vyc thanh tbi ndng thdn trong mau phan tich khdng khic biet ldn so vdi tdng tbi mau VHLSS 2012. Binh quin thu nhip/ngudi/thing ciia mau va tong miu theo thii ty la 2.090 va 2.000 ngin dong. Nhu viy, so mau phan tfch trong dl tai cd thi dai dien dugc cho tdng thg.
Cac die dilm kinh tl-xa hdi khic cua hd gia dinh dugc quan sat qua sd lieu trung binb va do lech chuin ciia cac tii sin liu bgn va die digm nha d trong Bing 2. Cot so trung binh cho bigt cd bao nhieu phin trim hg gia dinh cd tai sin hoic die diem nao do.
Vl dy, 90% hd gia dinh cd sd hflu TV miu, 80% cd xe miy, 97% cd tiep can vdi ludi dien. Do lech chuan cua bign sd tii sin cho bigt sy phin bd cua cic loai tai sin khac nhau nhigu hay it giua cic hg. Nhung tii sin phan bd kba khdng ddng deu gifla cac ho (do lech chuin Idn) thi qua phin tich PCA se cd trgng sd cao ban trong cic chi sd, va cic tii sin cd do lech chuin thip se cd trgng sd thip (McKenzie, 2005). Vf dy, tai san nao ma tit ca hg dgu cd hoac khdng cd thi se cd do lech chuan bing 0 va khdng cd gia tri dg dua vao dg tinb cic cbi sd. Ket qui, cic bien sd trinh bay trong Bing 2 cho thay do lech chuan cua cic bign li rat cao so vdi gia trj trung binb chung, ham y sy phu hgp ciia cac bign sd de dua vio tinh chi sd. Cd nhilu biln sd dugc xiy dyng da bi loai khoi PCA vi ban chit cd it y nghTa vi anh hudng din chi sd. Trong so dd cd cie biln nhu may may, TV tring den, miy xay sinh to, tudng bg tdng.
Bang 1
Thu nbap binh quan nhan khau/thang (ngin dong)
VHI SS Vung/khu vyc S6 miu Trung binh Dp lech chuan
Vimg
Dong bing song H6ng 1.987 2.393,01 2.009,23 2.350,6
1.623 2.061 642
1.122 1.901
1.499,39 1.804,21 2.057,14 3.163,03 1.969,34
1.591,32 1.455,72 1.851,74 4.073,73 2.265,54
1.258,4 1.505,2 1.643,3 3.172,8 1.796,7
Nguyin Hiru Dung. Tap chi Phat triln Kinh tl, 27(2), 17-34 25
, . . VHLSS Viing/khu VUC Soman Trung binh Dp lech chuan
Trung du va mien mii phia B§c Bac Trung Bp va Duyen hai mi6n Trung Tay Nguyen
Dong Nam Bp
Dong bang song Cliu Long Thdnh thi - ndng thon
Thanh thi 2.697 3.010,20 3.355,658 2.989,1 Nong thon 6.639 1.717,38 1.538,748 1.579,4 T6ng mau (n = 9.336) 9.336 2.090,85 2.297,64 1.999,8 Nguon: Kit qua phan tich va bao cao kit qua "VHLSS-2012
4.2. Kit qud xdy dung 3 chi sd
Trgng sd (hay digm tii cua cic bign sd) eua cic bign sd tii sin va die digm nhi d cua ba chi sd tit phan tich PCA rigng biet dugc trinh biy trong 3 cot tilp theo cua Bing 2 (DC, DA, LSI). Cbi sd LSI bao gdm cic bign sd cua 2 ehi sd tii sin liu bin (DA), vi die digm nha d (DC). Kgt qua xem xet dd tbi phin bd 3 cbi sd, die biet la chi sd miic sdng LSI khi chuin so vdi phin bd cua bai chi sd DA vi DC, phin bd dlu xung quanh sd trung binb. Kgt qui niy tuong ty nhu kgt qui ciia cic nghign ciiu trudc (Gunnsteinsson & cdng sy, 2010; Vyas & Kumaranayake, 2006) vl sd lugng biln tai sin nhj phin cing nhigu thi vin de chi sd bi co cym hay dirt doan it xiy ra. Cbi sd dugc phin phdi chuin se tao digu kien dg dang dl phin thanh cic nhdm kinb tl-xa bdi khic nhau. Kgt qua cflng him y cac bien sd su dyng de xay dung chi so la khi du vi hgp li.
26 Nguyin Him Dung. Tap chi Ph^t trien Kinh ti, 27(2), 17-34
C h l so n h a d vA no-i c u ' trCi ( P C )
Moan-4 30E-16 Std.Dev - 1 000 N -9,329
C h i SO mirc s o n g ( L S I )
Hinh 2. Kgt qui xiy dyng ba loai ehi so
Nguyen Hmi Dung. Tap chi Phat trijn Kinh t£, 27(2), 17-34 27
Cac trgng sd nay bilu thi mirc do anh hudng ciia nd den diem ciia chi sd khi bien sd do thay ddi tir 0 (khdng cd sd bun) din 1 (cd sd huu). Bien sd ducmg cd inh hudng lam gia tang miic sdng cua hd, va ngugc lai bien cd trgng sd im lam giam miic sdng ciia hg.
Vl du, hd cd nha ve sinh bang cau ca, khdng cd nha ve sinh, sir dung gieng dio cd miie sdng thip ban eic hg khdng cd die digm niy.
Mdi hd gia dinh tuy thugc vao miic do sd hfloi va die digm nha d khic nhau se cd mgt diem ve miic sdng khic nhau. Thdng thudng, cic tie gia (vi du, G-watkin, 2000;
Gunnsteinsson & cdng sy, 2010) va trong nghign ciiu nay sir dung cich phin chia theo ngu pbin vi. Ba cdt sau cimg trong Bing 2 trinh bay gii tri trang binh ciia cic bign sd phin theo 5 ngu phan vi d miic 20% thip nhit, 20% d ngu phan vi 3 (trang binh) va 20%
d ngu phin vi 5. Kgt qui cho thiy cd sy nhit quin bgn trong khi sir dung ehi sd dg phan nhdm miic sdng cic hg gia dinh.
Xu hudng sd hiiu cac tai san lau bgn va die digm nha d eua hd dien ra theo ki vgng.
Vi du, 20% hd cd miic sdng thip nhit (LSI-1) khdng cd sd bun miy tinh, miy giat, may digu hda, 30% hd sir dung nudc gigng dao, v i 24% khdng cd hd xi. Trong khi dd 20%
hd cd miic sdng cao nhat thi ti le hd sd hiiu cic tii sin niy theo thii ty la 59%, 77%, 35%, 7%, va 0%.
Bang 2
Ket qui PCA vg chi sd miic sdng, dac diem nhi d va tai sin liu ben ciia hd
Tai san/dac diem
Tdi sdn idu ben Xe dap Dien thoai ban Dien thoai di dpng Dau may Video TV mau Dan nhac May tinh
Tnmg binh
0,52 0,23 0,80 0,53 0,90 0,13 0,17
Dp lech chuan
0,52 0,23 0,80 0,50 0,30 0,34 0,37
Cac chi DC
s6 DC, DA, LSI DA
0,09 0,45 0,45 0,39 0,40 0,37 0,63
LSI
0,14 0,44 0,42 0,32 0,38 0,31 0,58
Trung ngu 1
0,31 0,62 0,54 0,29 0,66 0,02 0,00
binh phi phan vi
3
0,05 0,17 0,55 0,57 0,97 0,1!
0,05 in theo LSI
5
0,47 0,87 0,97 0,74 0,99 0,29 0,59
28 Nguyen Hiiu Dung. Tap chi Phat trien Kinh le, 27(2), 17-34
Tai san/dac diem
Til lanh Dieu hoa May giat May nuoc nong Bipga Noi com dien May hiit bui Lo vi song May xay sinh to Quat may Xe may Oto
Trung binh 0,47 0,07 0,21 0,16 0,66 0,78 0,03 0,04 0,16 0,86 0,80 0,01 Dgc diem nhd & vd nai cie tru Nuoc may
Gieng dao Nuoc mua Cau tu hoai Cauca Khong ho xi Dien luoi Cot be tong Cot gach Cot sit Mai be long
0,28 0,23 0,13 0,56 0,09 0,06 0,97 0,32 0,44 0,12 0,18
Dp lech chuan
0,50 0,26 0,41 0,36 0,47 0,41 0,16 0,21 0,36 0,35 0,40 0,11
0,45 0,42 0,34 0,50 0,29 0,25 0,17 0,47 0,50 0,32 0,39
Cac chi DC
0,45 -0,26 0,13 0,68 -0,32 -0,39 0,34 0,52 0,10 -0,48 0,68
! SO DC,
DA 0,70 0,60 0,71 0,64 0,62 0,49 0,40 0,53 0,61 0,37 0,43 0,26
DA, LSI LSI 0,69 0,56 0,68 0,64 0,63 0,52 0,35 0,47 0,55 0,40 0,37 0,23
0,48 -0,22
0,00 0,66 -0,23 -0,34 0,31 0,46 0,01 -0,32 0,51
Trung binh ph ngii phan vj 1
0,02 0,00 0,00 0,00 0,09 0,28 0,00 0,00 0,00 0,54 0,54 0,00
0,06 0,29 0,09 0,05 0,21 0,24 0,86 0,08 0,21 0,32 0,00
3 0,42 0,00 0,04 0,02 0,80 0,91 0,00 0,00 0,05 0,94 0,86 0,00
0,22 0,27 0,15 0,62 0,07 0,01 1,00 0,27 0,62 0,08 0,10
an theo LSI
5 0,97 0,35 0,77 0,64 0,98 0,97 0,12 0,21 0,53 0,97 0,97 0,05
0,65 0,07 0,09 0,99 0,00 0,00 1,00 0,67 0,32 0,01 0,53
Nguyin Httu DDng. Tap chi Phat triSn Kinh le, 27(2), 17-34 29
Tai san/dac diem
Tam lop Mai rom Tuong be tong Tuong gach Biet thu Nha kien co T 6m luoc ve cac chi So bien trong chi so
% phucmg sai PCA Eigenvalue
Trung binh 0,47 0,03 0,02 0,74 0,01 0,28 so
Dp lech chuan
0,50 0,18 0,16 0,44 0,08 0,45
Cac chi DC -0,31 -0,28 0,18 0,60 0,08 0,70
17 18,53
3,15
S6DC.
DA
19 25,57
4,86
DA, LSI LSI -0,16 -0,22 0,15 0,46 0,12 0,56
36 17,93
6,63
Trung ngu 1 0,57 0,15 0,00 0,25 0,00 0,03
binh phi phan vj
3 0,49 0,00 0,02 0,88 0,00 0,19
in theo LSI
5 0,34 0,00 0,06 0,93 0,02 0,72
4.3. Xem xit su tuang thich ciia chi sd miec song so v&i cdc cdch phdn chia theo chi sd bdng tiin
Miic sdng cua hd phin theo chi sd mu'c sdng vdi ngfl phin vi dugc chia theo thu nhap binh quin nhin khau/thing va chi tigu binh quan nhan khiu/thing dg xem xet sy nhit quin bgn trong khi sir dung eic chi sd bang tign vi chi sd mirc sdng. He sd tuong quan Pearson giu'a ngu phan vj theo chi sd miic sdng vi ngu phin vj theo thu nhap vi chi tieu binh quan diu ngudi/thing theo thu ty la 0,63 va 0,57, cd y nghTa thong kg miic I % cho thay miic do tuang thich cua cic chl sd d miic tuong ddi cao.
Ket qui so sinh phin bd cic hd gia dinh theo hai cich pbin chia ngfl phan vi dugc trinh bay trong Bing 3 cho thiy trong ngu phin vi thii nhit cd 54,04%) so hd phan theo chi sd mirc sdng eung nam trong nhdm phin vi 1 pbin theo thu nhip. Trong khi dd, ban 56% sd hd trong ngu phan vi 5 cflng dugc phin bd eung mdt nhdm theo c i 2 each phan chia. Ti le sd hd cung mgt nhdm theo hai cich phin chia phii hgp d miic khoing 30%
trong cic phin vi 2, 3 va 4. Ket qui nay tuong ty nhu ket qui cua Prakongsai (2006) khi so sanh giua cac hd gia dinh Thii Lan dugc phan theo cac chi sd tai sin vi thu nhip eua hd cho thiy 47 % sd bd nhdm dau tign dugc phin theo cic cbi sd tai sin phu bgp vdi nhflng phan loai theo thu nhip eua hd; va khoing 52 % sd hd trong nhdm thii nim. Khi
30 Nguyin Hilu Dung. Tap chi Phat triln Kinh tl, 27(2), 17-34
SO sinh phan bo cic hd vao 5 ngfl phan vj chia theo ehi so miic sdng va chi tieu binh quan hd/thang cflng eho kit qua tuang ty. Kit qui cua Rutstein va Johnson (2004) cung cho thiy cd mdi quan he gifl'a ngu phin vi theo phin ehi tieu va theo chi sd miic sdng.
Bang 3
So sinh phin bo cac bd theo ngfl phan vj LSI, thu nhip va chi tieu hg/thang Nhom
LSI 1 sohp
% 2 sohp
% 3 sohp
% 4 sohp
% 5 sohp
%
Ngu
QI 1.009 54,04 548 29,35
202 10,82
84 4,50
24 1,29
phan vj quan Q2 542 29,01
554 29,66
404 21,63
256 13,70
112 6,00
phan theo thu nhap binh nhan khau/thang
Q3 199 10,66
439 23,51
544 29,14
442 23,67
243 13,02
Q4 7 3,59 258 13,82
499 26,73
589 31,55
454 24,32
Q5 12 0,64
75 4,02 227 12,16
507 27,16
1046 56,03
Ngiiph
QI 1.025 54,90 470 25,17
187 10,02
107 5,73 78 4,18
an vj phan theo chi tieu binh quan nhan khiu/thang
Q2 552 29,55
522 27,94
398 21,31
244 13,06
152 8,14
Q3 212 11,36
487 26,08
509 27,26
376 20,14
283 15,16
Q4 69 3,70
296 15,85
508 27,21
574 30,74
420 22,50
Q5 9 0,48
92 4,93 266 14,25
566 30,32
934 50,03 dia li
4.4. Ddc diem kinh ti-xa hdi hd gia dinh theo khu vuc thdnh thi/ndng thon vd vimg
Khi phin theo khu vye thinh thi/ndng thdn cho thiy cd sy each biet gifl'a thanh thi va ndng thdn va cic bd cd chi sd miic song cao vl eic dac dilm nha d va tien fch nai cu trii, tai sin liu ben. Bing 4 trinh bay mdt sd khac biet vl nhung die dilm nay. Vi du, xet cic hd thudc nhdm LSI-I, khu vyc thanh thi khdng cd ho xf va mii ram ft han khu vuc ndng thdn, nhung ngugc lai thi nha cd mii bing tim Igp nhilu ban. Cac hd thudc nhom LSI-5, cd su- dung nude mua vi gilng dio d khu vyc ndng thdn nhilu han. Nhung dilu nay da ndi lgn sy hgp If cua kit qui phan tfch trong hien trang ndng thdn hien nay.
Nguyin HOu Dung. Tap chi Phat Iriln Kinh te, 27(2), 17-34 31
Bang 4
Mgt sd die diem nha va tien fch nai cu tni d thanh thi v i ndng thdn
Nhom „ Khong . Mai Tuong Gilng Nudc Khu vuc , . , Tam Icrp
LSI ho XI ' rom gach dao mua QI
Q2
Q3
Q4
Q5
Khi ip dyng chi sd LSI dg xem xet tinh hinh sd hiiu tai sin tai cic viing dja li cho thay cd nhieu sy khie biet vg sd hfln loai tai sin nay giiia eic vung. Ddng bang sdng Hdng va Ddng Nam Bd cd ti le sdhiiu tai sin eao nhit so vdi 6 vung. Vung ft phat trign thudng sd hiru cic loai tii sin it gii tri hon. Vi dy, xe dap la loai phuang tien giao thdng re tien sd hiiu nhigu han tai cic nhdm LSI-1 va LSI- 2 thudc viing 2 (Trang du va miin niii phia Bic), vung 4 (Tiy Nguyen), va vimg 6 (DBSCL). Tai sin dien thoai di ddng tai vung 2 (Trang du va mign niii phia Bic), 4 (Tiy Nguygn) va 6 (DBSCL) cd ti le cao nhit tai ngii phin vi I, va hd d ngfl pbin vi thip sd hun nhigu ban hd d ngu phan vi cao.ban (Hinb 3). Nhieu sy khae biet ve sd hflu cic tai sin khic tai cic viing dia If phan theo ngu phan vi LSI ed thg khai thic va phin tfch theo eich nay.
Thanh thi Nong thon Thanh thj Nong thon Thanh thi Nong thon
Thanh thi Nong thon
Thanh thi Nong thon
0,200 0,244 0,068 0,067 0,014 0,015 0,000 0,000 0,000 0,000
0,700 0,557 0,658 0,464 0,674 0,431 0,652 0,393 0,366 0,277
0,092 0,151 0,019 0,024 0,002 0,000 0,000 0,000 0,000 0,000
0,300 0,252 0,631 0,715 0.845 0,888 0,942 0,935 0,927 0,940
0,292 0,290 0,266 0,371 0,174 0,303 0,102 0,185 0,033 0,140
0,033 0,089 0,057 0,162 0,056 0,183 0,048 0,241 0,026 0,215
32 Nguyen In HOu Dung. Tap chi Phat triln Kinh te, 27(2), 17-34
iS5 H 4
= 3 :: 2
Deng bang Trung du va BSc Trung Bp Tay Nguyen Dong Nam Bp Dong bang song Hong mien nui phia va duyen hai song Ciru
Bac miin Trung Long
Hinh 3. Sd hiru dien thoai tai cic viing pbin theo ngu phan vi LSI 5. Ket luan va kien nghi
5.1. Kit lugn
Trong xu thg cic nudc ngay cang ip dung nbieu phuang phip khac nhau de dinh gia dieu kien kinh tg xa hdi hg gia dinh ma khdng phii dung cic chi sd do ludng bing tien nhu thu nhip vi cbi tigu thi vdi sy san cd cua sd lieu khio sat mirc sdng hd gia dinh VHLSS, nghign cuu da xem xet khi ning xay dyng cic chi sd khdng do ludng bing tien de do ludng muc sdng cac hg gia dinh VN.
Kgt qui cho thiy; (I) Ba loai chi sd (tai sin, die dilm nhi d va nai cu trii, miic sing) dugc xiy dyng theo phuang phip phin tieh thanh phan ehinh la phii hgp vdi sd lieu hien cd; (2) Mdi cbi sd se gin cho hd gia dinh mdt dilm so tuang iing vdi trgng so cua cac bign sd cd trong moi chi so. So dilm cang cao thi mue sdng cua hg cang cao; (3) Co sir tuong thich, nhit quin bgn trong giua chi sd dugc xay dyng vdi cac chi so truyin thing theo tbu nbap hoac chi tigu kbi phin bd cic bd vao nam ngfl phin vi tucmg ty cic nghien cuu trudc (Rutstein & Johnson, 2004; Vyas & Kumaranayake, 2006; Gunnsteinsson &
cdng sy, 2010). Ndi cich khic li chi so miic song cd thi dugc su' dung dl do ludng tinh trang kinb tg xa hdi cua hd gia dinh vi cbi so niy cho thiy nhfl'ng khic biet rit cd nghTa giua cic nhdm cd miic sdng khac nhau, die biet li doi vdi nhflng tai sin hoic tien ich
Nguyin Hiiu Dung. Tap chi Phat triln Kinh tl, 27(2), 17-34 33
cd trgng sd digm cao; va (4) Cic minh hga ve sir dung ehi sd miic sdng LSI cho thay cd khie biet ro vg tinh trang kinh te-xa hdi cua hd gia dinh tai khu vyc thanh thi/ndng thdn hoac giira cac viing dia If.
5.2. Kiin nghi
Dya vao kgt qui phin tfch, tic gia cd nhirng de xuat cho cic nghien cim tiep theo:
Thit nhdt, iing dung cic chi sd do ludng khdng phai bang tign dya theo cic sd lieu hien cd trong cac cudc khio sit miic sdng hd gia dinb VN dg phin tfch muc sdng tuang ddi giua cic hd. Die biet, can cd sy hien dien eua cic bien sd tai san liu ben cd trgng sd cao (cd miic inh hudng ldn) trong cic chi sd.
Thd- hai, khai thic sau hon cac chi sd dugc xay dyng theo phuang phip PCA trong nghien ciiu nay dg cd dugc cac khuyen eao cy thg ve tinh trang siie khde gia dinh, giio dye, nhan chiing hgc, ehit lugng cudc sdng sir dung trong viec hoach dinh chfnh sich phat trign 'vimg, dia phuang. Digu nay dugc thyc hien bang cich xay dyng chi sd rigng cho khu vyc ndng thdn, thanh tbi, va cic viing dia If khac nhau vi mdt sd die digm, tii sin phd bign d nai niy nhung khdng dai dien d nai khic. Cac bien sd sd hfln dat dai, tai sin phuc vu sin xuat cua bd (miy cay, may gat, dien tfch kho bai, sd lugng gia siic, v.v.) cin xem xet dua vio chi sd tinh rigng cho khu vyc thanh thi, ndng thdn.
Thuba, ip dung ddng thdi phuong phip khic nhu MCA, va sir dyng thgm thanh pbin thii hai dg phan tfch, so sinb sy nhit quin ve ket qui trong dieu kien sd lieu khio sit cua VN.
Thu tu, quy md hd gia dinh cd the anh hudng den mdt sd tii sin sd hfl'u nhu sd lugng phdng ngu, xe miy, din triu, bd. Do viy, ngu cic bign sd nay khi dua vio tinh chi sd cin cd sy digu chinh theo sd ngudi trong hd. Ngugc lai, cie bien sd khac nhu chit lugng ngudn dien, ngudn nudc, loai vit lieu xiy dyng nha khdng bi ehi phdi bdi sd ngudi trong hd thi dugc ma hda theo cich da thyc hien trong de tai.
Thii- ndm, mac du e i bien sd lien tue, bien sd chung loai, va bien sd nhi phin deu cd thg sir dyng trong phuang phip PCA dg xay dung cbi sd, nhung viec dien djch ket qui se gap nhieu khd khin. Cic bign sd trade kbi dua vao phuang phip PCA can phii dugc chuin bda dg cd phuang sai bang 1 va trung binh bang 0, ket qui sau ciing la thanh phin chinh cd sd trung binb bang 0, va tit c i cic bien sd cd anh hudng den thinh phan chi'nh (chi sd) theo trgng sd dugc xac dinh tir quy trinh phin tfch«
34 Nguyin Httu Dung. Tap chi Phdt triln Kinh tl, 27(2), 17-34
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