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Kinh tế lượng ứng dụng trong kinh tế và tài chính / Phạm Thị Tuyết Trinh cb., [và những người khác ...].

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<b><small>TRlfdNG DAI HOC NGAN HANG TP.HO CHf MINH</small></b>

<b>KHOA KINH TE QUOC TETS. PHAM TH! TUYET TRINH</b>

<i><b><small>(Chu bien)</small></b></i>

<b>W® TE IMG ft® DUNGTMNUa KINH TE Vfi Tfll CUMI</b>

<b><small>KnUSHNQ HOUSE</small></b>

<b><small>NHA XUAT BANKINH TgTP. </small></b><small>h</small>6<b><small>CHl MINHNAM 2016</small></b>

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thu’d’ng (Ordinary Least Square, OLS).

Ve co* ban, nhung phirong phap, ky thuat kinh te lu’O'ngdirge sir dung de phan tich cac van de trong tai chinh cunggiong nhir cac phirong phap dirge sir dung trong phan tfch kinh

te n6i chung. Tuy nhien, du* lieu tai chinh thirong c6 sir khacbiet nhat dinh so voi dir lieu kinh te vT mo. Dir lieu sir dung de

nghien ciru kinh te vT mo thirong virong phai hai van de. <i>Mot la,</i>

van de mau nhd lam thieu dir lieu san c6 de kiem dinh ly thuyet

hoac gia thuyet. Nguyen nhan la vi cac dir lieu kinh te vT mo nhirtai khoan quoc gia, ngan sach chinh phu, dan so va lao dong...

thirong dirge do lirong theo tan suat nam. Hai la, van de sai sot

chinh du* lieu (data revisions) sau d6, lam anh hirong den ketqu& nghien cun. Chang han, dau nam 2015 nha nghien cun thirc

hien iron lirgng tac dong eda san lirgng nen kinh te den dau tirvao linh virc cong nghe cao trong giai doan 1995 - 2014 t£r dirlieu dirge co* quan thong ke eda chinh phd cong bo (Chang hannhir o’ Viet Nam la Tong cue Thong ke). Den gan cuoi nam 2015,

i

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nha nghien cilu phat hien ra rang gia tri cua cac quan sat nam2013 va 2014 da thay doi do <i>cor</i> quan nay da dieu chinh du* lieu.

Nhirng van de nay hiem khi gap phai trong nghien cilu tai

chinh. Du- lieu tai chinh third* ng co tan suat cao han so vo'i dvr

lieu kinh te vT mo. Gia hoac lai nhuan tai san tai chinh co the

dirge thu thap hang gia, ngay, tuan... lam cho so lirgng quan

sat san cd de phan tich thirang rat Ian. Nha qui mo mau Ion,ket qua nghien cihi trong linh vgc tai chinh co dirge tinh tin

cay cao. Ngoai ra, dir lieu tai chinh nhir gia tai san dirge ghi

nhan khi giao dich thgc te dien ra hoac dirge niem yet trenman hinh cua nha cung cap thong tin. Kha nang sai sot hoacdieu chinh dir lieu mac du co the xay ra do thay doi phirang

phap do lirang dir lieu hoac loi danh may, van de khong

nghiem trong nhir so vdi trirang hgp sai sot va dieu chinh dir

lieu kinh te vT mo. Ben canh do, phan tich dir lieu tai chinhphai doi dien vo'i nhirng van de khac gan lien vo'i nhirng dacdiem rieng cd cua dir lieu tai chinh nhir do nhon virgt chuan

(leptokurtosis), bien dong nhom (clustering volatility), hieu

irng don bay (leverage). Nhirng khac biet nay doi hoi phdi cdnhirng phirang phap, ky thuat phu hgp de xir ly cac dir lieu tai

chinh va giai quyet cac van de trong tai chinh.

Tai lieu dirge tiep can theo hirong ling dung nham giupngtrai doc de dang hieu, lam chu va sir dung dirge cac phirang

phap, ky thuat kinh te lirgng. Cac noi dung dirge trlnh bay theohird'ng han che ham lirgng toan, thong ke va tap trung vao khiacanh irng dung cua tirng phirang phap, ky thuat ket hgp vo’i

khai thac cac tien ich san cd tir phan mem kinh te lirgng. Trongtirng chirang, song song vo'i phan thuyet la phan hird'ng dan

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irng dung tren bo dir lieu phu hop dirge lay tir 4 nguon tin cay,

gbm Thong ke Tai chfnh Quoc te (International Financial

Statistics, IFS), Tong cue Thong ke (General Statisics Office,

GSO), Dir lieu Tai chfnh va Kinh te Quandl va Trung tarn Hoinhap Khu vtre Chau A (Asia Regional Integration Centre, ARIC).Tai lieu cung dira vao phan hircrng dan tirng biro'c thao tac cuthe de thirc hien iro'C lirgng, kiem dinh bang phan mem EViewsva phan tfch chi tiet cac ket qua ircrc lirong, kiem dinh nham

giup ngircri doc tir thirc hanh va co the thirc hien nghien cun cua

rieng minh.

Von muc tieu giup nhumg doi tiromg dang va se can sir dung

kinh te lirong cho hoc tap, nghien cun co dirge mot tai lieu tieng

Viet tiep can theo hircrng irng dung don gian va cu the, tai lieudirge bien soan dga tren nhung kien thirc va kinh nghiem tfch

bien soan. Noi dung trong tai lieu con dirge bien soan dira theonhung giao trinh kinh te lirgng dirge sir dung rong rai tai cac

trirong dai hoc tren the gicri, trong do cac tai lieu tham khao chu

Cau true cua tai lieu gbm 6 chirong. Chirong 1 gicri thieu cac

dang cau true dir lieu dirge str dung trong phan tich kinh te, taichfnh va cac phirong phap phan tfch dir lieu co’ ban bao gbmphan tfch do thi, thong ke mb t£, thay doi tan suat dir lieu,

chuyen dang dir lieu, loai bo thanh phan mua vu cua dir lieu

thoi gian. Ngoai ra, cac biro'c thgc hien nghien ciru dinh lirgngcung dirge mo ta ngan gon trong chiromg nay. Chiro’ng 2 trinh

bay mo hinh chubi thai gian do,n bien va tong quan ve dir bao,

iii

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trong do noi dung chu yeu la hirang dan phirong phap trcrclirgng va du* bao mo hinh ARIMA theo tiep can Box-Jenkins.

Chirong 3 gidi thieu ve mo hinh tghoi qui vectcr (VAR), mo hinh

chuoi thoi gian da bien dirge sir dung pho bien nhat de giai

quyet van de noi sinh. Phan tich nhan qua Granger, phan irngday va phan ra phirong sai cung dirge trinh bay nhtr la nhung

phirong phap phan rich chu yeu cua mo hinh VAR. Chirong 4

trinh bay mo hinh dong lien ket va hieu chinh sai so de xu* ly cac

dir lieu chuoi then gian khong dung dong then kham pha tac

dong ngan han va dai han. Chirong 5 gioi thieu cac mo hinh phu

hgp veri dir lieu tai chinh co dac diem phirong sai thay doi, baogbm hai loai mo hinh don gian nhat la ARCH va GARCH. Chirong

6 gioi thieu hai mo hinh co’ ban nhat de phan tich dir lieu bangla mo hinh tac dong co dinh (FEM) va mo hinh tac dong nglu

nhien (REM).

Mac dii nhom bien soan da rat no lire, tai lieu chac chan se

con nhung thieu sot nhat dinh. Nhom bien soan rat mong nhandirge y kien dong gop cua ban doc de tiep tuc hoan chinh tai

lieu. Moi y kien dong gop xin vui long giri ve dia chi email:

<i></i> Nhom bien ‘soan xin tran

trong cam on moi y kien dong gop.

<b>NHOMBIEN SOAN</b>

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<b>HU’O’NG DAN SIT DUNG</b>

<sub>■</sub>

<b> I</b>

Bo du* lieu thirc hanh du'o’c cung cap cho ban doc diroa dang

file excel (.xlxs) va workfile cua EViews (.wfl). De <i>co</i> bo du* lieu

thtrc hanh di kern tai lieu, ban doc gtri email:

- Co tieu de: De nghi cung cap bo du* lieu thirc hanh

- Giri den dia chi:

Ngoai ra, trong qua trinh tim hieu Kinh te Itromg trng dung,quy ban doc co thac mac can giai dap, nhom bien soan rat mongnhan du'o’c email chia se cua quy ban doc. Trong kha nang cothe, chung toi se giai dap cac thac mac cua quy ban doc nhu* mot

str dong hanh va ho trcr quy ban doc tren con du'dmg hoc tap va

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<b>MUC LUC</b>

<sub>■ ■</sub>

<b>Ld'i mo* dau... ... iHu'6'ng dan sir dungbo dir lieu thirc hanhvMuc luc...vi</b>

<b>Danh muc hop...xviiiDanhmuc tir viettat... xixCHU'O’NG 1. CAU TRUCDU* LIEU VA<small>■</small>PHAN TICH DU*</b>

1.3.1. Cac thanh phan cua du- lieu chuoi thd’i gian 11

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<b><small>CHiraNG 2. U O’C LU'C/NG VA DU' BAG BANG MO HINH</small></b>• •

<b><small>CHUOI THO! GIAN DCTN BIEN... 35</small></b>

2.1. Gio'i thieu ve kinh te lirong chuoi thoi gian va mot sokhai niem... 36

2.1.1. Gio’i thieu ve kinh te lu'ong chuoi thoi gian... 36

2.1.2. Mot so khai niem trong kinh te lu'ong chuoithen gian...37

2.2. Gio'i thieu mo hinh chuoi thoi gian do,n then... ... 40

2.3. Mo hinh trung binh triro't (MA)... 41

2.3.1. Gio'i thieu mo hinh MA...V412.3.2. Dac diem mo hinh MA... 42

2.3.3. Tfnh kha nghich cua mo hinh MA...43

2.4. Mo hinh tir hoi qui (AR)...45

2.4.1. Gio'i thieu mo hinh AR... 45

2.4.2. Dac diem mo hinh AR... 46

2.4.3. Dieu kien dung cua mo hinh AR(p)... 47

2.5. Mo hinh trung binh tru’O't tir hoi qui (ARMA)... 49

2.6. Qua trinh ti'ch htyp va mo hinh ARIMA... 50

2.7. Ham tir tiro'ng quan va ham tir tirong quan rieng phan....51

2.7.1. ACF va PACF cua qua trinh AR...53

2.7.2. ACF va PACF cua qua trinh MA... 54

2.7.3. ACF va PACF cua qua trinh ARMA... 57

2.8. Xay dung mo hinh ARMA theo tiep can Box-Jenkins...58

2.8.1. Nhan dang mo hinh... 59

2.8.2. U’crc lu'ong mo hinh... 60

2.8.3. Kiem dinh chan doan... 60

2.9. Kiem dinh tfnh dung cua chuoi thcri gian dvra vao ACF...66

vii

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2.10. Xay dung mo hinh ARMA cho chuoi lam phat theo

tiep can Box-Jenkins...69

2.11. Tong quan ve du* bao...79

2.11.1. Tai sao phai thirc hien dirbao?... 79

2.11.2. Cac loai du* bao...80

2.11.3. Danh gia tfnh chfnh xac cua dir bao...83

2.12. Dirbao bang mo hinh chuoi tho-i gian...86

2.12.1. Kyvong co dieu kien...86

2.12.2. Dir bao gia tri tiromg lai cua qua trinh MA(q)...87

.2.12.3. Dir bao gia tri tirong lai cua qua trinh AR(p)... 89

2.13. Dir bao lam phat bang mo hinh ARMA...90

Tom tat noi dung...95

<b>CHITONG3. MOHINH TH HOI QUIVECTCT...99</b>

3.1. Mot so khai niem...100

3.1.1. Phtrong trinh dang rut gon va phirong trinhcau true...100

3.1.2. Van de nhan dang...101

3.1.3. He phirong trinh dong thoi, van de noi sinh vavi pham gia dinh CLRM... 104

3.1.4. He phirong trinh tarn giac/ He phirong trinhde qui...106

3.2. Mo hinh tir hoi qui vecto- (VAR)...107

3.2.1. Mo hinh tir hoi qui vecto- dang cau true (SVAR)... 107

3.2.2. Mo hinh tir hoi qui vecto- dang rut gon (VAR)...109

3.2.3. ITu va nhiro-c diem cua mo hinh VAR...Ill3.3. <i>U'&c</i> Itro-ng moi quan he giira ph^t trien tai chfnh v&tang trirong kinh te bang mo hinh VAR...113

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3.4. Kiem dinh chan doan mo hinh VAR...118

3.4.1. Tfnh on dinh cua mo hinh...118

3.4.2. Kiem dinh chan doan doi voi phan dir...119

3.5. Kiem dinh y nghTa khoi va kiem dinh nhan qua...124

3.6. Kiem dinh quan he nhan qua Granger giu'a phat trientai chinh va tang trirong kinh te...128

3.7. Phan irng day va phan ra phirong sai...129

3.8. Tac dong cua phat trien tai chinh den tang trirongkinh te qua phan tfch phan ung day va phan raphirong sai...133

3.9. Mo hinh VAR co bien ngoai sinh...140

Tom tat noi dung... 141

<b>CHU'O’NG 4. urcrcLU'O’NG QUAN HE NGAN VA DAI HAN:MO HINH DONG LIENKET VA HIEU CHiNH SAI SO...143</b>

4.1. Kiem dinh tfnh dung va kiem dinh nghiem don vi...144

4.2. Phirong phap kiem dinh nghiem don vi/ kiem dinhtfnh dung...146

4.2.1. Quan sat ACF cua chuoi dir lieu... 147

4.2.2. Kiem dinh nghiem don vi/ kiem dinh tinh dung.... 147

4.3. Kiem dinh nghiem don vi bang EViews...152

4.4. Dong lien ket/ dong tfch hcrp...155

4.4.1. Tai sao can phai tim hieu phirong phap donglien ket?... 155

4.4.2. Dong lien ket la gi?...157

4.4.3. Phirong phap kiem dinh quan he dong lien ket....159

4.5. Mo hinh hieu chinh can bang/ hieu chinh sai so...160

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4.6. U'O’c lircrng quan he dai han va ngan han bang phircrng

phap Engle-Granger...1634.7. Str dung phirong phap Engle-Granger de u'6c* lirong

quan he dai han va ngan han...1644.7.1. Quan he dai han va ngan han cua thay doi ty

gia va chenh lech lam phat then thuyet PPP

(Vi du 1)... 164

4.7.2. Quan he dai han va ngan han cua ty gia there va

can can thirong mai (Vi du 2)...1714.8. U’O’C lircrng quan he dai han va ngan han bang phiro’ng

phap Johansen...174

4.8.1. Mo hmh vecto’ hieu chinh sai so (VECM)...1744.8.2. Phirong phap kiem dinh dong lien ket theo

Johansen...1774.8.3. Cac bu'6'c u'O’c lirong quan he dai han va ngan

han theo Johansen...1804.9. U’O’c lirong quan he dai han va ngan han cua sanlirong, lam phat, cung tien bang phirong phap Johansen...183

Tom tat noi dung...201

<b>CHU’O'NG5. DO LU’O'NG VA Dll' BAO BIEN DONG</b>

<b>TRONGTAl CHINH: MOHINH ARCH-GARCH...203</b>

5.1. Tai sao phai do lirong va dir bao bien dong trong

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5.5. Kiem dinh tac dong ARCH cua chuoi lai nhuan

5.8. Here Iirong bien dong Icri nhuan VN-Index bang mo

hinh GARCH(1,1) •....223

5.10. Mo hinh GARCH co them bien giai thfch: Anh hirong

5.11. Dir bao bien dong lai nhuan VN-Index bang mo hinh

<b>CHHUNG 6.MO HINHHOI QUI Dfr LIEU BANG235</b>

6.3.1. Gia thuyet 1: pl, p2, va P3 khong doi theo don

6.3.2. Gi& thuyet 2: pl khac nhau theo cac dan vi

6.3.3. Gia thuyet 3: pi khac nhau theo cac don vi cheova thoi gian; p2 va p3 khong doi theo thoi gian va

6.3.4. Gi& thuyet 4: pi, p2, va p3 khac nhau theo

cac dan vi cheo nhirng khong thay doi theo

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6.4. Van de bien bi bd sot...253

6.5. Mo hinh tac dong co dinh (FEM)...254

6.5.1. Gicri thieu mo hinh... 254

6.5.2. Kiem dinh su* khong dong nhat... 256

6.5.3. Phuong phap uvc luong FEM...257

6.5.4. FEM co dac trung theo thoi gian...261

6.5.5. FEM co dac trung theo don vi cheo va thcri gian.... 262

6.6. Mo hinh tac dong ngau nhien (REM).... 262

6.7. Kiem dinh Hausman...265

6.8. U’o'c luong mo hinh dau tu Grunfeld bang mo hinhFEM va REM...267

6.9. Kiem dinh ty tuong quan...272

6.10. Kiem dinh mo hinh dinh gia tai san theo Fama vaMacBeth (1973)...275

Tom tat noi dung...278

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<b>DANH MUC </b>

<sub>■</sub>

<b>BANG</b>

Bang 1.2. Tan suat cua mot so chuoi du* lieu thdi gian ...3

Bang 2.1. Dac diem ACF va PACF cua mohinh ARMA(p, qj---57

Bang 2.4. Du* bao trunc s bu'6'c veri mau chbng lan va

Bang 2.6. Tong ho* ket qua du* bao tru*6'c-2-bu ’6*c bangdu

Bang 4.1. Gid tri bac bo gid thuyet khong co quan he dong

lien kettheo phu*ong phap Engle va Granger 160

Bang 4.3. Cac bu*6*c c lirong quan he dai han va ngan

Bang 4.4. Trinh bay ket qua kiem dinh dong lien ket theoJohansen

xiii

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<b>DANH MUC </b>

<sub>■</sub>

<b>HINH</b>

Hinh 1.1. Chuoi tho-i gian cd tfnh xu hiro’ng... 12

Hinh 1.2. Chuoi thcri gian co ti'nh chu ky...12

Hinh 1.3. Chuoi thoi gian co tfnh mua vu...13

Hinh 1.4. Chuoi thoi gian co tfnh ngau nhien...14

Hinh 1.5. Chuoi thd*i gian co cac quan sat ngoai lai...15

Hinh 1.6. Chuoi thoi gian co diem chuyen hiromg...16

Hinh 1.7. Chuoi th da gian co diem gay cau true... 16

Hinh 1.8. Vi du<sub>• </sub>du' lieu<sub>• </sub> tan suat nam va du* lieu<sub>•</sub> tan suatquf du'p’c noi suy...23

Hinh 1.9. Chuoi dir lieu dang so tuyet doi va danglogarithm co* so tir nhien...25

Hinh 1.10. Chuoi thoi gian <i>co</i> thanh phan mua vu (GDPN)va sau khi loai bo thanh phan mua vu (GDPSA)...31

Hinh 1.11. Cac bu'6'cxay dung mo hinh kinh te lirong...32

Hinh 2.1. Muc tieu cua phan tfch chuoi thoi gian...37

Hinh 2.2. ACF va PACF cua AR[1): Yt = 0.5Yt-i + ut...54

Hinh 2.3. ACF va PACF cua AR(1): Yt= -0.5Yt-i + ut...54

Hinh 2.4. ACF va PACF cua MA(1): Yt = -0.5ut-i + ut...55

Hinh 2.5. ACF va PACF cua MA(2): Yt = 0.5ut-i - 0.25ut-z+ ut...55

Hinh 2.6. ACF va PACF cua ARMA(1, 1): Yt = 0.5Yt-i +0.5ut-i + Ut...*...•...56

Hinh 2.7. ACF cua chuoi thoi gian ditng...68

Hinh 2.8. ACF cua chuoi thoi gian khong dCtmg... 69

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Hinh 2.9. Nhan dang mo hinh hinh ARMA(p, q) dira vao

Hinh 2.10. Ket qua iro’C lirong mo hinh ARMA dirng va kha

Hinh 2.11. Ket qua iro’C lirong mo hinh ARMA khong dirng 74

Hinh 2.13. Ket qua kiem dinh tu* tirong quan phan dir

Hinh 3.1. Ket qua lira chon bac tre toi iru theo cac tieu

Hinh 3.3. Nghiem nghich dao cua da thirc dac trimg tir

Hinh 3.7. Ket qua kiem dinh nhan quci Granger 129

Hinh 4.1. Chuoi du* lieu khong dirng CPIVN va CPISG 145Hinh 4.2. Ket qu& iron lirong bang OLS co hien tirong hoi

phan bac 1

xv

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Hinh 4.5. Ket qua udc luong dong lien ket va ECM bang

phuong phap Engle-Granger: Birac 1 (Vi du 1).... 166Hinh 4.6. Ket qua u6*c luong dong lien ket va ECM bang

phuo'ng phap Engle-Granger: Kiem dinh tfnh

dtrng cua phan du- (Vi du 1)...167Hinh 4.7. Ket qua kiem dinh dong lien ket Engle-Granger... 170Hinh 4.8. Ket qua u’o’c luong dong lien ket va ECM bang

phuong phap Engle-Granger: Buo’c 1 (Vi du 2).... 172Hinh 4.9. Ket qua udc luo-ng dong lien ket va ECM bang

phuo'ng phap Engle-Granger: Kiem dinh ti'nh

dung cua phan du (VI du 2)...173

Hinh 4.10. Ket qua udc luong dong lien ket va ECM bang

phuomg phap Engle-Granger: Bude 2 (Vf du 2).... 173Hinh 4.11.<i> U&c luong dong</i> lien ket va VECM bang phuong

phap Johansen: Ket quci lua chon bac tre toi uu___ 185Hinh 4.12. U’o’c luong dong lien ket va VECM bang phuong

phap Johansen: Tomtat kiemdinh donglien ket___189

Hinh 4.13. U’o’c luong dong lien ket va VECM bangphuong phap Johansen: Ket qu& kiem dinh

dong lien ket (Phan 1}...191

Hinh 4.14. U’o’c luong dong lien ket va VECM bang

phuong phap Johansen: Ket qu& kiem dinh

dong lien ket (Phan 2)...194Hinh 4.15. U’o’c luong dong lien ket v£ VECM bang

phuo'ng phap Johansen: Ket qu& VECM...197Hinh 4.16. U’o’c luong dong lien ket vh VECM bang

phuong phap Johansen: Ket qu& kiem dinh

nhan qu2 Granger... 199

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Hinh 5.1. Phan phoi co do nhon virp't chuan va phan phoi

chuan... 206

Hinh 5.2. Dac diem bien dong nhom cua dir lieu tai chfnh... 207

Hinh 5.3. Tiromg quan bien dong trong tai chfnh...208

Hinh 5.4. Phiromg sai co dieu kien va phirong sai khongdieu kien...209

Hinh 5.5. Ket qua kiem dinh tac dongARCH...217

Hinh 5.6. Ket qua U'O'C lirorig mo hinh GARCHfl, 1)...225

Hinh 5.7. Ket qua kiem dinh tir tirong quan cua binhphtrorig phan dir ...227

Hinh 5.8. Ket qua U'O’C lirorig mo hinh GARCH(1, 1) cothem bien crisis...229

Hinh 5.9. Ket qu& U’O'C lirong mo hinh GARCH(1, 1) cobien crisis giai doan 2006-2010...231

Hinh 5.10. Ket qua dtr bao trung binh va phirorig sai cuaVN-Index trong nam 2011... ...232

Hinh 6.1. Ket qu& hoi qui OLS du* lieu gop...245

Hinh 6.2. Ket qua hoi qui mo hinh LSDV...249

Hinh 6.3. Ket qua hoi qui theo gia thuyet 4... 252

Hinh 6.4. Ket qua U'O’C lirorig FEM...268

Hinh 6.5. Ket qua kiem dinh sir khong dong nhat cua domvi cheo va tho*i gian... 270

Hinh 6.6. Ket qu& U’O'C lirorig REM...271

Hinh 6.7. Ket qu& kiem dinh Hausman...272

Hinh 6.8. Ket qua kiem dinh tu* tiro’ng quan cua mo hinhdu' lieu bang... 274

xvii

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<b>DANH MUC HOP</b>

<sub>■ </sub><sub>■</sub>

Hop 2.1. Toantu-tre...42

Hop 2.2. Da thirc nghich dao...45

Hop 2.3. Dinh luat phan tach Wold... 48

Hop 2.4. Phirong trinh va nghiem dac trirng...49

Hop 2.5. Du* bao dongva dir bao tinh...94

Hop 3.1. Cac bu'6'c kiem dinh nhan qua Granger...126

Hop 4.1. Cac birac kiem dinh bac tich hop...155

Hop 4.2. Mo hinh ECM nhieu bac tre... 162

Hop 5.1. GARCH[1,1) tircrng diromg vo*i ARCH vohan bac...220

Hop 5.2. Cac birac iron liromg mo hinh ARCH/ GARCHbang u’o'C liromg hop ly circ dai...222

Hop 6.1. Du* lieu cheo ket hop va dir lieu bang... 236

Hop 6.2. Phirong phap binh phirong be nhat du* lieu gop___ 247Hop 6.3. U’o'C liromg binh phirong be nhat co bien gi&... 259

Hop 6.4. U’o’C lirong OLS va u’o'C liromg GLS...265

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<b>DANH MUC TU</b>

<sub>■</sub>

<b>*VIET TAT</b>

kien thay doi ttr hoi

xix

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DGP <sup>Data</sup> <sup>Generating</sup> <sup>~</sup>Qua<sup> x</sup>tnnh tao du* lieu<sup>A</sup>Process

correction model can bang/ sai so

FEM Fixed Effect Model • / <sup>Mo</sup><sup> hinh</sup>/ <sup>tac</sup> <sup>dong</sup>‘ 5 <sup>co</sup>dinh

Office *

Financial Statistics Quoc te

Dummy Variable co bien gi&

MAE <sup>Mean</sup> <sup>Absolute</sup><sup> Error trungbinh</sup><sup>Sai so tri </sup><sup>'</sup> <sup>tuyet </sup><sup>doi</sup>

</div><span class="text_page_counter">Trang 24</span><div class="page_container" data-page="24">

MAPE <sup>Mean </sup><sup>Absolute</sup>Percentage Error

Sai so phan tram tri

tuyet doi trung binh

Autoregression <sup>Tu</sup><sup>*</sup> <sup>hoi </sup><sup>qui</sup><sup> vecto</sup><sup>*</sup>

Correction Model

chinh sai so

<b><small>XV'</small></b>

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<b>Muctieuhoc tap</b>

• Phan biet dune cac cau true dir lieu;

• Thur hien dircrc cac phan tich du* lieuco' ban bang EViews;

• Mo tci diro-c cac birac xay dung mo

hinh kinh te lirong.

1

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<i><small>Chtrang 1. Cau true dir lieu vd phdn tfch dir lieu ccr bdn</small></i>

<b>1.1. Cac loai <small>■ ■</small>cautrue du lieu</b>

Co ba loai cau true du* lieu ducrc su dung pho bien trong

phan tfch cac van de kinh te, tai chfnh gbm: du lieu cheo, du lieu

chuoi tho-i gian va du* lieu bang.

vi cheo thu 2), 3 (don vi cheo thu ba)....N (don vi cheo thu N).Tong so luong quan sat cua dulieu cheo ducrc ky hieu la N.

Tang truerng tong san pham quoc noi (GDP) cua 5 quoc giaASEAN nam 2012 trong Bang 1.1 co dang du lieu cheo. Cac don

vi cheo khac nhau <i>i(i = 1, 2, 3,4, 5} la</i> cac quoc gia thanh vien

<i>Ghichu: Tang trirang GDP 5 quocgia ASEAN num 2015</i>

Ngubn: IFS (2016)

toan thu thap tai mot thdi diem nhat dinh. Chang han, bang cauhoi khao sat doi veri cac ho gia dinh co the duuc thu thap vao

nhien, trong nhung truung hop nay su khac biet ve thcri diem

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<i><small>Chirang 1. Cau true dir lieu va phan tfch dir lieu cor bdn</small></i>

thu thap dir lieu thirong chap nhan dirge vi khong anh hirong

dang ke den ket qua khao sat.

<b>1.1.2. Du*lieuchuoi then gian</b>

Mot chuoi thdi gian [Time series) la mot tap hop cac quansat cua mot bien so dirge thu thap theo then gian gan lien voimot tan suat quan sat cu the. Tan suat la sir third" ng xuyen maquan sat dirge ghi nhan nhu* hang gio; hang ngay, hang tuan,hang thang, hang quf, hang nam. TCrng quan sat la gia tri cua

bien so tai tho*i gian nhat dinh, dirge ky hieu la <i>Yt (t =1, 2,3,</i>

<i>T) </i>voi <i>T</i> la tong so lirgng quan sat. Du* lieu chuoi dir lieu thoigian, <i>Yt, thtrong </i>dirge viet dtroi dang:

<i><small>{Yl</small> Y2,<small>Yt}</small></i>

<b>Bang1.2. Tan suat cua mot so chuoi durlieu then gian</b>

Chi so Scin xuat cong nghiepChi tieu chinh phu

Cung tien

Gia tri cua cd phieu

hang thang [monthly), hangqui [quarterly)

hang nam [annually)

hang thang [monthly)

[as transactions occur)

Bang 1.2 cho thay tan suat pho bien cua mot so dir lieuchuoi thcri gian. Tan suat "khi giao dich phat sinh" la dac diem

rieng co cua dir lieu tai chinh. Nhieu du* lieu tai chinh khongdirge ghi nhan thirong xuyen theo dinh ky (nhir hang thang).Chang han, gia cd phieu cua mot cong ty dirge ghi nhan thay doi

khi c6 giao dich moi hoac niem yet moi. Thong thirong gia cd

3

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<i><small>Chuang 1. C&u true dir lieu va phdn tich dir lieu ca ban</small></i>

phieu khong thay doi giu*a 5 gid- chieu hom nay den 8 gio* sanghom sau vi thi trirong dong cua khong cd giao dich mo'i phat

Isinh; dugc ghi nhan ft khi thi trirong vira mo* cua, sap dong cua

va gia an trira; dugc ghi nhan nhieu hon trong thcri gian giao

dich con lai. Hau het cac ky thuatva phtrong phap kinh te lirong

deu dua tren gia dinh cac quan sat dirge thu thap theo dinh ky

deu dan cua tan suat Trong nhung trirong hgp nhir vay, nha

nghien cun thirong Irra chon mot tan suat phu hop, khi do, quansat dirge gia dinh cd gia tri khong doi trong thcri gian giua haithdi diem lien ke.

Bang 1.3 cho vf du du lieu GDP gia nam 1994 (ty dong) cua

Viet Nam trong giai doan 1996 - 2011. Chuoi GDP cd tan suat

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<i><small>Chtrcrng 1. Cdu true dir lieu vd phfin itch dir lieu ca ban</small></i>

hoac dinh tfnh (qualitative) (nhtr ngay trong tuan, xep hang tinnhiem...).

Do cac sir kien trong qua khu* co the anh hiromg den tirong

lai, phan ti'ch dir lieu chuoi thai gian dac biet quan tam den giatri qua khir va tirong lai cua cac bien so, cung nhu* su* tirongquan cua gia tri bien so theo thcri gian. Dac diem nay lam cho

phan ti'ch dir lieu tho*i gian trer nen kho khan horn so <i>v&i dir </i>lieucheo. Trong dtr lieu chuoi thoi gian, bien so tre (laggedvariable) 1 giai doan ky hieu la Y<i>t-r, tre</i> s giai doan diro-c ky hieu

la <i>Yt-s. </i>Bien so trircrc (lead variable) 1 giai doan dircrc ky hieu la

<i>Yt+i> </i>tru-dc <i>k</i> giai doan ky hieu<i> la Yt+k.</i>

<b>1.1.3. Dfrlieu bang</b>

Dir lieu b&ng (Panel data) la dang du* lieu ket ho* cua dir

lieu chuoi thd*i gian va dir lieu cheo. Co the goi du* lieu b&ng la

<b>Bang 1.4. Vidu du* lieu bang</b>

7 <small>MalaysiaPhilippinesSingaporeThailandVietnam</small>

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<i><small>Chu’O’ng 1. Cau true dir lieu va phan tfch dir lieu ca bdn</small></i>

Tang trudng GDP cua 5 quoc gia ASEAN trong giai doan

2010-2014 trong Bang 1.4 co dang du* lieu bang, trong do cacdo'n vi cheo dirge quan sat la 5 quoc gia ASEAN, thdi gian dirge

quan sat la giai doan 2010-2014.

Co the sir dung cau true ma tran de dien dat bien so GDPnay nhir sau:

Dirlieu bang cua bien Yu luc nay se la ma tran TxN trong do

<i>t theo</i> hang doc va i theo hang ngang:

<b><small>^K7V,2014 ^TH,2014 — ^M/1,2014</small></b>

<b><small>^KAT,2010</small></b> <i><small>Yth,</small></i><b><small>2010</small></b> <small>■ ■ •</small> <b><small>^M/1,2010JvW,2011</small></b> <i><small>Yt</small><b><small> H,2011</small></b></i> <small>• • ■</small> <i><small>YmA,</small><b><small>2011</small></b></i>

<i><b><small>Y[t=YVN2012</small></b><small>Yth,</small></i><b><small> 2012</small></b> <small>• • •</small> <i><small>YmA,</small></i><b><small>2012</small></b>

<i><small>Yvn,</small><b><small>2013</small></b><small>Yth,</small><b><small>2013</small></b></i> <small>• • •</small> <b><sup>^M/1,2013</sup></b>

<b>1.2.Phan tfchdir lieu co*ban</b>

Trude khi su* dung dir lieu de udc lirgng, thong thudng nhanghien cuu phai <i>"c&m" </i>dirge dir lieu, noi each khac la hieu dirge

dac diem du lieu dang su dung. Phan nay trinh bay ngan gon

nhung each thuc khac nhau de phan tich du lieu bang cac do thiva thong ke do'n gi^n.

<b>1.2.1.Quan sdtbang du lieu</b>

Bude khdi diem de phan tfch du lieu la nhln vao bang dulieu (spreadsheet) de quan sat kho&ng dao dong cua du lieu.Doi vdi du lieu chuoi thdi gian, can xem x6t them thdi diem batdau va ket thuc cua du lieu.

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<i><small>Chircrng 1. Cau true dir lieu vd phdn tfch dir lieu cor bdn</small></i>

Khi nhin vao gia tri cua dir lieu, can liru y: (i) nhirng quansat ngoai lai (outliers) la nhung quan sat co gia tri 16n hoac nhd

bat thirong so veri nhung quan sat khac; (ii) nhung diem gaycau true (structure breaks) trong du* lieu chuoi thoi gian ladiem ma co dien bien khac biet so voi xu hirong chung (chang

han trong mot giai doan tang lien tuc cua du* lieu thi co mot vaigia tri tang manh rbi giam manh); (iii) diem chuyen hunng cuadu

* lieu la nhung diem ma tai do gia tri quan sat dao chieu.

Nhung trirdng hop nay can liru y vi co the anh hirong Ion denket qua hoi qui.

<b>1.2.2. Phan tich dothi</b>

Str dung cac do thi cho phep thay dtro'c birc tranh tong the

ve dien bien cua du* lieu, dong thoi cung cho phep thay dtro'cnhung quan sat ngoai lai va diem gay, diem chuyen hirong de

hon so voi nhin tir bang dir lieu. Cac cong cu do thi thirong

diro-c str dung gbm:

<i>- Histogram:</i> cho thay cac chi so lien quan den phan phoixac suat cua bien so. De ve bieu do phan phoi xac suat cua motchuoi dir lieu trong EViews, thirc hien cac thao tac sau:

• Nhap Quick/ <b>Series Statistics/ Histogram andStat</b>

• Go ten chuoi vao hop <b>Seriesname•OK</b>

<i>- Do thiphdn tan (scatter plots): </i>cho thay sir ket hop gia tri

cua hai chuoi dir lieu (chang han X, Y) de thay dirge moi quan

he giira chung neu co. Do thi thirong dirge trinh b&y dtroi dang

nhung cham tron voi true hoanh (true X) va true tung (true Y).Tir do thi c6 the nhin thay xu hirong va moi quan he giira X, Y.

7

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<i><small>Chuang 1. Cdu true dir lieu vd phfin tich dir lieu cor bdn</small></i>

Ngoai ra, con de xem xet mire phan tan cua du* lieu va de xem

cac gia tri ngoai lai.

<i>- Do thi dang dirang(line graphs}:</i> phu hop de so sanh dien

bien cua cac chuoi du* lieu theo thoi gian hay de xem xet moiquan he cua hai chuoi X,Y. Ngoai ra, t£r do thi dang dirong co the

nhin ro tfnh xu hirong cua dir lieu.

<i>-Dothi cot (bar graphs): </i>du’o’c sir dung de so sanh theo th di

gian (nhir doanh so nam nay so voi doanh so nam tru’de) hay de

so sanh gitra cac hang muc. Du- lieu se du'o’c sap xep theo dang

cot dung voi true hoanh la thoi gian, cac the loai,... va true tung

trinh bay nhung gia tri (nhir doanh so ban hang A theo thd*igian; haygia tri ban dirpx cua hang A, B, C..)

<i>- Do thihinh tron (pie charts):</i> du'o’c bieu thi diroa dang hinhtron, thong thirong de do kfch co* cua cac hang muc hay ty le

phan tram dong gop cua tung hang muc trong tong the chung

ma theo do tong cac hang muc nay hop lai se thanh 100%. Do

thi nay thtrong chi du'o’c dung cho mot chuoi du* lieu v6*i tat caso deu la dtrong, de xem ty le dong gop. Do do, do thi nay

thirong ft du'o’c sir dung trong dinh lirong.

De ve do thi trong EViews, thirc hien cac thao tac sau:• Nhap Quick/ <b>Graph...</b>

• Nhap ten chuoi/ cac chuoi can ve do thi vao hop<b> SeriesList</b>

<b>1.2.3. Thong ke mo ta</b>

Thong ke mo ta cung cap cac chi so lien quan den ph^n phoi

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<i><small>Chirang 1. Cau true dir lieu vd phdn tfch dir lieu ccrbdn</small></i>

xac suat cua chuoi dir lieu gbm co trung binh, pheromg sat dolech chuan, sai so chuan, do nghieng, do nhon.

<i>- Trung binh (Mean), </i>ky hieu E(X) = dirp'C tfnh toan theo

cong thu*c: <i> X =</i>

<i>- Phirerng sai (Variance), ky</i> hieu var(X) = (7y, derac tfnh toan

mere dao dong cua du* lieu quanh gia tri trung binh nen dero’c

dung de xem mere do tan xa cua dir lieu. Trong tai chinh,

pheromg sai cua gia tai san tai chinh con la chi so do lerdmg rui ro

dau tir vao tai san tai chinh do.

<i>- Do lech chuan (Standard deviation),</i> ky hieu <i>ox, </i>la can bac

hai cua phiromg sai, dircrc tfnh toan theo cong there: o<i>x — </i>

<i>-xT^x-- Do nghieng (Skewness),</i> do Itrcrng ser bat doi xirng cua phan

phoi xac suat quanh gia tri trung binh. Trong phan phoi chuan

xac suat hai ben mang tfnh doi xerng deu nhau, doi xumg qua giatri trung binh cung chinh bang gia tri trung vi (median) va lanod du- lieu tap trung 16m nhat (mod). Neu do nghieng deromg(>0) co nghla la phan phoi xac suat co duoi phdi dai, co nghTa latrung binh < trung vi, noi each khde, chuoi du* lieu co phan phoi

xac suat khong deu, nha nghien cum da thu thap mot so dir lieunhan gid tri qud 16m. Ngerac lai, do nghieng am (<0) co nghTa la

phan phoi xac suat khong deu, co duoi trai dai, nha nghien cumda thu thap mot so dir lieu nhan gia tri qua nho. Gia tri do

nghieng dumc tinh theo cong there:

<i>skewness =</i>

9

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<i><small>Chuvng 1. Cau true dir lieu vd phdn tfch dir lieu cor bdn</small></i>

<i>- Do nhon(Kurtosis) </i>do lirdmg do nhon hoac bang cua phanphoi xac suat. Do nhon cua phan phoi chuan bang 3. Neu do

nhon 16-n ho*n 3 (>3), phan phoi dirge goi la co do nhon virgtchuan (leptokurtic), neu do nhon nhd horn 3 (< 3), phan phoidirge goi la co do nhon dircri chuan (platykurtic). Gia tri do

nhon dirge tfnh theo cong thirc:. sF=1(Xi-x)4kurtosis = ■

Trong EViews, de tfnh toan cac tri so thong ke mo ta, thirchien cac thao tac sau:

• Nhap Quick/ Group Statistics/ Descriptive Statistics.

• Chon Common Sample khi sir dung qui mo mau chung

cho cac chuoi; Individual Sample khi sir dung qui mo

mau rieng cho tirng chuoi. Hai Iga chon nay chi khacnhau khi so lirgng quan sat co gan gia tri trong cac chuoikhac nhau.

• Nhap ten chuoi/ cac chuoi can phan tfch thong ke mo U

vao hop Series List.

Ngoai cac gia tri thong ke mo ti o tren,de phan tfch moitiromg quan giira hai hay nhieu bien so, he so hiep phtro'ng sai(covariance) va he so tirong quan (correlation) cung dirge sir

Hiep phtromg sai cua 2 chuoi, ky hieu cov(X, Y), dirge tfnh

theo cong thirc:

<i>cov(X,= E{[X- E(X)][Y- E(Y}]}</i>

Hiep phtremg sai dirge dung de xem xet rnu'c tiromg quan

tuyen tfnh giira hai bien <i>X, Y. </i>Neu hai bien <i>Xt Yco mu'e</i> bien dong

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<i><small>Chuang 1. Cau true dir Hep 6a phan tfch dir lieu ca ban</small></i>

ciing chieu nhau thi <i>cov(X,Y)</i> se duong (>0), ngucrc lai hai bien

X, <i>Y</i>bien dong ngiro'c chieu nhau thi <i>cov(X,Y)</i> se am (<0). Va khi

<i>cov(X,Y) =0</i> thi hai bien khong co moi quan he tuyen tmh. Tuy

nhien, <i>cov(X, Y) </i>chiu anh huong cua don vi cua <i>hai bien X vaY;</i>

do vay, khong the nhan xet ve do Ion trong moi tirong quan cua

hai bien nay dira vao <i>cov(X,</i> Y)

De khac phuc nhirgc diem cua hiep phuong sai, he so tirongquan duo*c sir dung. Theo do, he so tirong quan dune tmh nhtr

<i>P~ crxcrY</i>

He so tirong quan <i>(p)</i> duong (hay am) dung de xem xet moi

tirong quan tuyen tmh cua X va <i>Y </i>la cung chieu (hay ngucrcchieu). Ngoai ra, <i>p con </i>do mire do manh yeu trong moi tirongquan giua hai bien nay, biet rang<i>-1 < p < 1.</i>

chuoi trong EViews dune thirc hien bang each:

• Chon <b>Quick/ Group Statistics/ Covariances</b>

• Chon <b>Quick/ Group Statistics/ Correlations1.3. Du*lieu chuoi then gian va nhumgxu*ly co* ban1.3.1. Cac thanhphancua du lieu chuoi then*gian</b>

Chuoi thcri gian co 4 thanh phan:

<i>-Xuhwang (trend, Tt):</i> dien bien tang hoac giam nhat quancua chuoi theo thcri gian. Hinh 1.1 cho thay GDP Viet Nam tronggiai doan 1996-2011 (du* lieu trong Bang 1.3) co xu hirong tangmanh.

11.

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<i><small>Chircrng 1. Cau true dir lieu vd phdn tfch dir lieu ca bdn</small></i>

<i>Ghichu:GDP Viet Namgiai dogn 1996-2011</i>

Nguon: GSO (2016)

<b>Hinh 1.1.Chuoi then gian cotfnh xuhird'ng</b>

<b>Hinh 1.2. Chuoithen gian cotinhchuky</b>

<b><small>54 ■ "i r i""i i i “i i‘ i i r t~i T"r—i itt—i”'i—i—ri " i i i r i i -r—t—r—t—r—r~</small></b>

<b><small>1 1 1 1 1__ t 1 1 1 1 t t 13</small></b>

<b><small>I t 1___III fill I I___1___1__</small></b><i><b><small>t__</small></b></i><b><small>1___1___I---1---1___I___1---L</small></b>

<i>Ghi chu: Ty le thatnghiepCanadagiaidogn1976-2012</i>

Nguon: IFS (2016)

<i>- Chu ky (Cycle, Ct): sir lap lai</i> cua dien bien tang giam sau

mot thd'i gian (dai hon 1 nam) va thu-ong khong co dinh kho&ngthoi gian tang hoac giam. Hinh 1.2 cho thay tfnh chu ky erta ty le

that nghiep Canada, trong do, cSc dinh cua chu ky ro-i v£o cacnam 1983/ 1993, 2003 cac day cua chu ky ro*i vao cac nam1980,1990, 2000,2009.

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<i><small>Chuang 1. Cau true dir lieu va phdn t(ch dir lieu cor ban</small></i>

<i>-Mua vu (Seasonal,St): </i>str lap lai cua dien bien tang giamtrong mot nam, thu'd’ng xuat hien o’ cac du* lieu co tan suat caonhu

* thang, qui. Str lap lai nay thu'dng co dinh vao thang hoac

qui nhat dinh trong nam. Hinh 1.3 cho thay dien bien chi so sanxuat cong nghiep cua Viet Nam hang thang bi anh hirdrig boathanh phan mua vu, trong do chi so san xuat cong nghiep thap

nhat vao nhung thang dau nam do san xuat giam o' nhtrng thangtet, va cao nhat vao cac thang cuoi nam do cac doanh nghiep giatang san xuat dap irng nhu cau tang cao. Ngoai ra, de dang nhan

thay rang, ngoai tinh mua vu, chuoi san xuat cong nghiep trong

Hinh 1.3 con co tinh xu hircrng.

<b>Hinh 1.3. Chuoi thengian co tinh mua vu</b>

<i>Ghi chu:Ch! so san xuat cong nghiep Viet Nam giai doanthang</i>

<i>1/2008-12/2015Nguon: GSO (2016)</i>

<i>-Ngau nhien (Irregular, It):</i> dien bien mang tinh ngau nhien,

khong cd tinh he thong va khong the du* doan. Hinh 1.4 cho thay

qui luat.

13.

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<i><small>Chircrng 1. Cau true dir lieu va phan rich dir lieu ca ban</small></i>

<b><small>I II III IV I II III IV I II III IV I II III IV2009 2010 2011 2012</small></b>

<i>Ghichu: Mac thaydoi (lainhugn) ngay cua ty gid JPY/USD</i>

Moi quan he giira mot chuoi thdi gian (Yt) va cac thanh

phan cua no dirge the hien qua mo hinh, third'ng gap la mo hinh

nhan tmh (Multiplicative Components Model) va mo hinh cong

tinh (Additive Components Model).

- Mo hinh nhan tinh (1.1) xem cac gia tri cua mot chuoi thd'i

gian dirge tao thanh bd*i tich so cua tirng thanh phan xu htrong(Tt), chu ky (Ct), miia vu (St) va ngau nhien (It).

- Mo hinh cong tinh (1.2) xem cac gia tri cua mot chuoi thd'i

gian dirge tao thanh hoi tong cac gia tri cua cac thanh phan

cua nd.

Liru y rang, khong phai tat ca dir lieu chuoi thd'i gian deu c6

du 4 thanh phan nay, tuy nhien, thanh phan ngau nhien luonton tai trong moi chuoi thd'i gian. Cdc thanh phan khong ngaunhien (xu htrang, chu ky, mua vu) trong nhieu tru'dmg hgp can

<b>Hinh1.4. Chuoithen gianco tinh ngaunhien</b>

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<i><small>Chirang 1. Cau true dir lieu va phdn t(ch dir lieu cor bdn</small></i>

phai du'crc loai bd tuy muc di'ch cua nha nghien cun.

Ngoai nhung thanh phan tren, trong dir lieu chuoi thai giancon co 3 dac diem quan trong la quan sat ngoai lai, diem chuyenhu'6'ng va diem gay cau true. Hinh 1.5 cho thay co mot so quansat ngoai lai trong dien bien loi nhuan ngay cua chi so congnghiep Dow Jones. Hinh 1.6 cho thay diem chuyen huorig cuachuoi ty le that nghiep cua Y. Hinh 1.7 cho thay diem gay cau

true cua chuoi chi so gia dau hang nam cua My. Nhu* da de cap &tren, nhumg dac diem nay can dac biet liru trong qua trinh

phan ti'ch chuoi then gian vi chiing co anh htrorig manh den ket

qua u'6'c lu'O'ng.

<b>Hinh1.5. Chuoi thd*igian</b> <i><b>co </b></i><b>cac quansat ngoailai</b>

<i>Ghi chu: Lai nhuan ngaycua chi socong nghiep Dow Jones (Dow</i>

<i>JonesIndustryIndex} giai dogn1/1/1980 31/9/1990</i>

Ngubn: Quandl (2016)

15

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