Mã số: ……………. PHẢN ỨNG CỦA TỶ GIÁ HỐI ĐOÁI TRƢỚC CÚ SỐC CHÍNH SÁCH TIỀN TỆ, ỨNG DỤNG MÔ HÌNH DSGE VÀ SVAR CHO VIỆT NAM
M s: .
PHN NG CA T GI HI OI TRC
C SC CHNH SCH TIN T,
NG DNG M HNH DSGE V SVAR CHO VIT NAM
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TM TT TI
L do chn ti
Vit Nam trong qu trnh hi nhp vi nn kinh t ton cu, hot ng xut
khu, nhp khu hng ha,dch v ngy cng pht trin, tng trng vi tc cao d
kinh t quc gia cng nh tnh hnh th gii ang phi i mt vi nhiu kh khn.
Th trng ngoi hi hnh thnh v ngy cng pht trin, Vit Nam tng lng d
tr ngoi hi ln cao. kim sot lm pht, ngn hng nh nc thc hin cc chnh
sch tht cht tin t....
Trong tnh hnh , vic xem xt s bin ng ca t gi hi oi l rt quan
trng trong chnh sch tin t ca mi quc gia chnh v vy, ti ny mun hng
ti cc phn ng ca t gi hi oi trc c sc chnh sch tin t nhm m t mt
cch xc thc nhttrong vics dng cc cng c hu ch v kinh t lng
Mc tiu nghin cu
Bi vit tp trung vo phn tch trng hp nn kinh t nh m thng quan m
hnh DSGE.c lng cc tham s ca m hnh v tp trung vo hm phn ng y
xem xt n tc ng ca cc c sc kinh t ngoi sinh n nn kinh t nh th no.
Ngoi ra,bi vit cn xem xt thm s ph hp trong vic s dng cc m hnh
VAR m phng li cc phn ng ca cc bin kinh t khi phi i mt vi cc c
sc t gi thng mi, cng ngh, lm pht th gii, sn lng th gii v t bit l
c sc chnh sch tin t -xem xt s truyn dn ca t gi hi oi .
Tm kim mt cng c hiu qu thc hin cc chnh sch v m, nhm
chng ti tin hnh thc hin m hnh DSGE ang c s dng ph bin cc
ngn hng trung ng ca nhiu nc trn th gii.
Phng php nghin cu
Bi vit xy dng m hnh DSGE cho nn kinh t nh m theo cch tip cn
ca Bayesian vi cc bin kinh t. Sau da vo cc bin quan st: l hng sn
lng (output gap), lm pht, li sut danh ngha, thay i t gi hi oi danh ngha
v t gi thng mi c lng cc tham s cho cc bin ca m hnh DSGE. Xy
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dng phn phi tin nghim cho cc tham s cha bit ca m hnh. T cc bin quan
st, xy dng phng trnh likelihood cng vi phn phi tin nghim thit lp t
trc xc nh cc phn phi hu nghim cho cc tham s. Cui cng, da vo
phng php Monter Carlo v Markov chain Monte Carlo (MCMC) tm tt thng
k li phn phi hu nghim ca tham s. T cc kt qu trn, chng ti c lng
hm phn ng y (IRF) xem xt phn ng ca cc bin trc tc ng ca cc c sc
kinh t v m.
Sau chng ti c lng thm cc m hnh VAR Recursive vi cch thit
lp thay i trt t ca cc bin c c hm IRF. Sau em so snh vi hm
IRF t m hnh DSGE la chn m hnh VAR Recursive c thit lp ph hp
xem xt phn ng ca cc bin trc tc ng ca c sc tht cht chnh sch tin t.
Ni dung nghin cu
Bi vit da trn tng ca ba bi nghin cu chnh: Lubik, T.A.,
Schorfheide, F., 2007. Do central banks respond to exchange rate move-ments? A
structural investigation, Jarkko P. Jskel, David Jennings (2011): Monetary policy
and the exchange rate: Evaluation of VAR models v gn y nht Tingguo
Zheng,Huiming Guo (2013): Estimating a small open economy DSGE model with
indeterminacy: Evidence from China.
Chng ti c lng m hnh DSGE vi 5 bin quan st c c cc tham
s ca m hnh, c lng hm phn ng y v phn r phng sai xem xt s tc
ng ca nhng c sc kinh t v m n nn kinh t ca Vit Nam.
Sau khi c c hm IRF ca DSGE chng ti tip tc c lng m hnh
VAR theo hai dng: VAR quy (recursive VAR) v VAR du hiu hn ch (sign-
restricted VAR). Trong VAR quy, chng ti thit lp cc cch p t khc nhau. T
c lng c cc hm IRF ca cc m hnh VAR sau xem xt vi hm IRF
c lng trc ca DSGE cng vi nhng vn puzzle xut hin (nu c)
nhn nh v m hnh VAR.
ng gp ca ti
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Xy dng c mt m hnh DSGE c s so snh v c th c s dng
nh gi phn no tnh hnh kinh t ca Vit Nam. c lng hm IRF xem xt
phn ng v mc phn ng, thi gian tr v trng thi n nh ca cc yu t kinh
t v m khi chu tc ng ca cc c sc trong nc v th gii.
Xy dng m hnh VAR theo nhiu cch p t trt t khc nhau i vi VAR
quy v p t du phn ng ca cc bin trong m hnh VAR du hiu hn ch.
Hng pht trin ca ti
Trong m hnh DSGE vn tn ti nhiu tham s khng tht s phn nh c
tnh hnh Vit Nam. Th nht :do khch quan v nhiu hn ch v d liu ( di, tn
tin cy) v cch phn tch la nn m hnh khng trnh khi nhng sai st v mt k
thut v phng php v ng thi do hn ch ch quan ca chng ti cha th nm
bt c nhng tinh ty trong m hnh v khai thc s dng ph hp. Th hai: Cc
tham s khi a vo tin nghim th khng hon ton ging nhau cc quc gia,vic
a vo hng lot t m hnh ca Trung Quc cng khin cho m hnh ca chng ti
khng tht s lm ng, tt nh nhng g chng ti mong mun. Th ba, chng ta
khng th xem nhng tc ng ca cc bin nc ngoi nh mt bin ngoi sinh tht
s v trong iu kin hi nhp hin nay, tt c cc quc gia u cn phi xem xt n
mi bin ng khng ch trong nc m cn trn th gii, v nhng bin ng
v nn c a vo m hnh khi c lng c c mt ci nhn tng quan v
ton din hn.Th t, c nhiu m hnh c s dng c lng cc yu t v m,
vic lm ca chng ti ch quan st c mt vi kha cnh, v c th c nhiu
phng php ph hp hn vi tnh hnh ca Vit Nam. Cui cng, hin nay nhiu nh
nghin cu xy dng pht trin v hon thin m hnh DSGE, c nhiu hng
nghin cu nh p t gi tr tham s ri c lng hay m hnh t c lng
tham s hoc c hai.
T , chng ti hng n vic m rng m hnh thm cc bin nc ngoi
nh mt bin ni sinh xem xt phn ng ca nn kinh t nh th no trc c c
sc trong v ngoi nc ton din hn. Tip theo,tm kim nhng nguyn nhn dn
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n cc puzzle v ci thin m hnh VAR hn ch bt nhng nguyn nhn do vn
k thut.
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MC LC
DANH MC T VIT TT ...................................................................................... 3
DANH MC BNG ................................................................................................... 5
DANH MC HNH .................................................................................................... 6
1. TNG QUAN V CC NGHIN CU TRC Y ................................. 8
1.1. Cc nghin cu v chnh sch tin t: .................................................................. 8
1.1.1. Jonathan Kearns and Phil Manners (2005) ............................................. 8
1.1.2. John B. Taylor (2001): .......................................................................... 11
1.2. Cc l thuyt v vn puzzle ........................................................................... 15
1.3. Cc nghin cu dng m hnh VAR xem xt t gi hi oi v cc puzzle ...... 17
1.3.1. Almuth Scholl, Harald Uhlig (2008) .................................................... 17
1.3.2. Almuth Scholl, Harald Uhlig (2009) .................................................... 19
1.4. Cc m hnh DSGE trong thc nghim: ............................................................ 22
1.4.1. Jarkko P. Jskel, David Jennings ...................................................... 22
1.4.2. Thomas A. Lubika, Frank Schorfheide ................................................. 27
1.4.3. Tingguo Zheng, Huiming Guo (2013) .................................................. 28
2. PHNG PHP NGHIN CU .................................................................. 29
2.1. Cc l thuyt v xy dng m hnh DSGE ........................................................ 29
2.1.1. Lch s v l thuyt ca m hnh DSGE .............................................. 29
2.1.2. Cc trng phi trong m hnh DSGE ................................................. 29
2.1.3. Cc bc xy dng c bn ca m hnh DSGE ................................... 31
2.1.4. Tng quan v gii php cho m hnh DSGE: ....................................... 33
2.2. M hnh Structural Vector Autoregression (SVAR) .......................................... 33
2.2.1. Tng quan m hnh VAR ..................................................................... 33
2.2.2. Phng php uc lng SVAR ............................................................ 35
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2.2.3. Hm phn ng y v Phn r phng sai ........................................... 36
3. M HNH DSGE CHO NN KINH T NH M V C LNG CHO
VIT NAM ............................................................................................................ 37
3.1. M hnh DSGE cho nn kinh t nh m SOE: .................................................. 37
3.1.1. M hnh nn kinh t nh m c th ha ............................................... 38
3.1.2. Gii php v s (Numerical) : ............................................................... 40
3.2. c lng m hnh DSGE cho Vit Nam ......................................................... 41
3.2.1. Xy dng phng trnh o lng : ....................................................... 41
3.2.2. M t d liu ......................................................................................... 42
3.3. La chn tin nghim ......................................................................................... 47
3.4. Kt qu c lng .............................................................................................. 49
3.5. Phn tch hm phn ng y .............................................................................. 52
3.6. Phn tch phn r phng sai ............................................................................. 56
4. KT QU T M HNH VAR ..................................................................... 57
4.1. VAR quy theo cc cch p t....................................................................... 57
4.2. VAR hn ch du hiu ........................................................................................ 63
5. KT LUN ..................................................................................................... 65
TI LIU THAM KHO ........................................................................................... 1
PH LC A: KT QU KIM NH TNH DNG. .............................................. 5
PH LC B: PHN PHI TIN NGHIM V HU NGHIM CA THAM S 7
PH LC C: THNG TIN K THUT THC HIN C LNG DSGE ........ 8
PH LC D: PHNG PHP C LNG THAM S ...................................... 9
PH LC E: THUT TON DU HIU HN CH SIGN RESTRICTIONS . 11
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DANH MC T VIT TT
DSGE Dynamic stochastic general equilibrium
M hnh cn bng ng tng th ngu nhin
VAR Vector Auto-Regression
T hi quy Vect
GDP Gross Domestic Product
Tng sn phm quc ni
ECB European Central Bank
Ngn hng trung ng Chu u
UIP Uncovered Interest Rate Parity
Ngang gi li sut khng phng nga
PPP Purchasing Power Parity
Ngang gi sc mua
REER Real Effective Exchange Rate
T gi hi oi thc hiu lc
NEER Nominal Effective Exchange Rate
T gi hi oi hiu dng danh ngha
IRF Impulse Response Function
Hm phn ng y
SOE Small Open Economy
Nn kinh t nh, m
CPI Consumer Price Index
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Ch s gi tiu dng
AR Auto Regressive
T hi quy
MCMC Markov chain Monte Carlo
IMF International Monetary Fund
Qu tin t quc t
SBV State Bank of Vietnam
Ngn hng nh nc Vit Nam
SVAR Structural VAR
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DANH MC BNG
Bng 1: Tp hp s kin ca c, Canada, New Zealand, Anh. ................................................ 8
Bng 2: D liu ca c, Canada, New Zealand, Anh. .............................................................. 9
Bng 3: Ngun d liu s cp ca m hnh ............................................................................ 43
Bng 4: Kim nh tnh dng cho cc bin quan st ............................................................... 47
Bng 5: Phn phi tin nghim ca cc tham s ..................................................................... 49
Bng 6: Kt qu c lng hu nghim ca cc tham s ....................................................... 52
Bng 7: Phn r phng sai theo cc c sc c s .................................................................. 56
Bng 8: p t du hiu trong m hnh VAR du hiu hn ch ............................................. 63
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DANH MC HNH
Hnh 1: Tp hp kt qu 4 loi tin t: la c, la Canada, la New Zealand v
ng Bng Anh. ............................................................................................................ 10
Hnh 2: Mt cch iu ha ca delayed overshooting puzzle. ................................ 15
Hnh 3: Mt cch iu ha ca forward discount puzzle. ....................................... 16
Hnh 4: Mt cch iu ha ca exchange rate puzzle. ............................................. 16
Hnh 5: Bng chng delayed overshooting puzzle theo cch p t th nht .......... 18
Hnh 6: Bng chng delayed overshooting puzzle theo cch p t th hai. .......... 19
Hnh 7:c: Phn ng vi c sc chnh sch tin t,dng VAR cu trc. .................... 20
Hnh 8:Canada: Phn ng vi c sc chnh sch tin t,dng VAR cu trc. ............. 21
Hnh 9:New Zealand: Phn ng vi c sc chnh sch tin t,dng VAR cu trc. ... 21
Hnh 10: Thy in: Phn ng vi c sc chnh sch tin t,dng VAR cu trc. .... 22
Hnh 11: Hm IRF trc c sc chnh sch tin t ca DSGE. .................................. 24
Hnh 12: Hm IRF trc c sc chnh sch tin t ca p t 1ca VAR quy. ..... 25
Hnh 13: Hm IRF trc c sc chnh sch tin t ca p t 2 ca VAR quy. .... 25
Hnh 14: Hm IRF trc c sc chnh sch tin t ca VAR du hiu hn ch. ........ 26
Hnh 15: GDP thc (gi so snh nm 1994) ................................................................. 44
Hnh 16: th li sut chit khu t 2000 2011 theo qu ....................................... 45
Hnh 17: REER, NEER v t gi USDVND theo thi gian. ........................................ 46
Hnh 18: Hm phn ng y ca DSGE. .................................................................... 54
Hnh 19: Hm phn ng y ca DSGE di tc ng ca c sc chnh sch tin t 55
Hnh 20. VAR quy p t 1 ..................................................................................... 57
Hnh 21. VAR quy p t 2 ..................................................................................... 59
Hnh 22. VAR quy p t 3 ..................................................................................... 61
Hnh 23: Phn phi IRF m hnh VAR du hiu hn ch ............................................ 64
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Hnh 24: 20 phn ng gn vi trung v nht m hnh VAR du hiu hn ch ............. 64
Hnh 25: Phn phi tin nghim v phn phi hu nghim ca cc tham s. ............... 7
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1. TNG QUAN V CC NGHIN CU TRC Y
1.1. Cc nghin cu v chnh sch tin t:
1.1.1. Jonathan Kearns and Phil Manners (2005)
The impact of monetary policy on the exchange rate: a study using
intraday data
Bi nghin cu ny s dng d liu ni nht (intraday data) c lng hiu
ng ca s thay i chnh sch tin t ln t gi hi oi. Tc gi s dng nghin cu
s kin (event study) vi mt s thi k c la chn cn thn cho bn quc gia
(Australia, Canada, New Zealand v Vng quc Anh y l cc quc gia m chnh
sch tin t khng tp trung vo t gi hi oi v quyt nh c a ra trc khi n
c thi hnh) m bo rng s thay i trong chnh sch tin t l yu t ngoi
sinh ca t gi hi oi.
Thit lp s kin
Bng 1: Tp hp s kin ca c, Canada, New Zealand, Anh. Ngun: Jonathan
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Kearns and Phil Manners (2005): The impact of monetary policy on the exchange
rate: a study using intraday data
D liu
Bng 2: D liu ca c, Canada, New Zealand, Anh. Ngun: Jonathan Kearns
and Phil Manners (2005): The impact of monetary policy on the exchange rate: a
study using intraday data.
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Kt qu:
Hnh 1: Tp hp kt qu 4 loi tin t: la c, la Canada, la New Zealand v
ng Bng Anh.
Th nht, tnh trung bnh, mt s tht cht bt ng 0.25% s dn n s gia
tng t gi 0.35%, vi cc c lng i vi mi quc gia ring r t - %. Cc
kt qu ny ch bo rng s thay i ca chnh sch tin t ch chim mt phn rt nh
trong s bin ng quan st thy ca t gi hi oi nhng quc gia ny.
Th 2, s thay i trong chnh sch tin t c hiu ng khc nhau ln t gi ph
thuc vo vic ngi dn k vng nh th no vo chnh sch tng lai. Cc tc gi
a ra mt kt qu bt ng l s k vng vo chnh sch tng lai c mt tc n
ln hn i vi t gi hi oi (khong 0.4%) nhiu hn so vi ch do s thay i
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trong chnh sch tin t m khng c s thay i trong k vng chnh sch tng lai
(khong 0.2%).
Kt lun:
-Th nht, t gi tng trung bnh khong 1 % trc s gia tng bt ng
1% trong chnh sch li sut. i vi cc quc gia ring r khong 1 1.8%. tnh
trung bnh, mt s tht cht bt ng 0.25% s dn n s gia tng t gi 0.35%, vi
cc c lng i vi mi quc gia ring r t - %.
- Tc ng ca chnh sch tin t ln t gi hi oi c tm thy s xy ra
gn nh ngay lp tc. Nu tc gi s dng mt ca s s kin (event window) m
kt thc sau khi quyt nh chnh sch c a ra, cc c lng cng khng thay
i, ch bo rng cc thng tin c phn nh nhanh chng vo trong t gi hi
oi. Mc d, s dng mt ca s s kin hp trong khng c cc s kin nh
dng khc xy ra, c sc chnh sch tin t ch gii thch khong 10 -20% s bin
ng ca t gi. Nhn chung, cc kt qu xut rng chnh sch tin t ch chim
mt phn nh trong cc bin ng quan st c ca t gi hi oi.
Th 2, bi nghin cu ny a ra mt bng chng mi rng khng phi tt
c cc bt ng trong chnh sch u dn n nhng hiu ng ging nhau ln t gi.
S k vng vo chnh sch tng lai c tm ra c tc ng ln hn cc bt ng
trong chnh sch ti thi im ra quyt nh thay i chnh sch. Mt s gia tng
1% (0.25%) cuar li sut hin ti v li sut tng lai lm tng t gi khong 1.7%
(0.4%). Cc kt qu c lng cho cc quc gia n l khong 1.3 2.2%. ngc
li mt bt ng trong chnh sch ch dn n mt s thay i c th on trc ch
0.9% (0.2%). Cc kt qu ny, a ra s tin on khng bit trc s thay i ca
t gi cn bng trong di hn, bi v s phn ng ngay lp tc trong t gi hi oi
cao hn so vi l thuyt ngang gi li sut xut, a thm mt s kh hiu
ca thc nghim.
1.1.2. John B. Taylor (2001):
The Role of the Exchange Rate in Monetary Policy Rules
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Trong bi nghin cu ny, Taylor tng hp v tm tt cc nghin cu v vai tr
ca t gi hi oi trong quy lut chnh sch, ng thi a ra cc li gii thch hp
cho cc kt qu trc.
Tc gi xem xt li cc ng trong mt s nghin cu gn y v tnh a ra
mt chnh sch tiu chun: Laurence Ball (1999), Lars Svensson (2000), and myself
(1999b). Cc nghin cu ny xem xt quy tc chnh sch dng:
it = ft + gyt + h0et + h1et-1
trong : it l li sut danh ngha ngn hn c a ra bi ngn hng trung
ng, t l t l lm pht, v yt l s chnh lch ca GDP thc v GDP tim nng, et l
t gi hi oi thc (et tng c ngha l s tng gi tr ng ni t - yt gi gin tip).
Trong phng trnh trn, khng c h s chn vi ng l t l lm pht mc tiu
bng 0 v li sut v t gi hi oi c o lng bng t l vi gi tr cn bng di
hn. Dng quy tc chnh sch tuyn tnh nh trn ch l mt trng hp n gin ca
cc dng phi tuyn tnh vi cc tr ca sn lng, lm pht, li sut v t gi hi
oi.
Cc thng s chnh sch l f, g, h0 v h1. Nu f > 1, g > 0, v h0 = h1 = 0, th quy
tc chnh sch khng phn ng trc t gi hi oi (Taylor, 1993). Cc thng s h
trong phng trnh bng 0 l quy tc chnh sch tin t trong nn kinh t ng v khc
khng l quy tc chnh sch tin t trong nn kinh t m, tuy nhin thut ng ny c
th dn n nhm ln bi v trong thc t, mt chnh sch ti u c th thit lp cho c
h0 v h1 u bng 0, hay xp x nh th.
Mt cu hi v vai tr ca t gi trong quy tc chnh sch l liu rng cc thng
s h c nn bng khng v nu nh vy th gi tr v du ca chng nh th no. V
d, mt li gii thch ca quy tc thc nghim c tho lun bi Obstfeld v Rogoff
(1995) a ra rng h0 nn nh hn khng v h1 bng khng. Mt t gi cao hn so vi
mc chun s dn n ngn hng trung ng gim li sut ngn hn, thng qua
chnh sch tin t ni lng.
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tr ca t gi hi oi trong eq (1) cho php s phn ng ng phc tp hn
so vi ch c phn ng n gin ca t gi hin ti. V d, nu h1 dng v h0 m
nhng gi tr tuyt i ca h0 ln hn h1, do , phn ng ca li sut ban u b p
mt phn trong thi k tip theo. Mt gii thch khc ca quy tc thc nghim a ra
bi Obstfeld v Rogoff l h0 < 1 v h1 = - h0; do , li sut phn ng trc s thay
i trong t gi hi oi; iu ny c th l mt gii thch i s tt hn cho tng
rng mt s gia tng trong t gi hi oi s dn n ni lng tin t, nhng khng c
m hnh cu trc m phng mt cch ngu nhin quy tc v tht s kh khn
tm ra li gii thch no tt hn.
Ball (1999) tm ra h0 = -0.37 v h1 = 0.17. ng tm ra y l cc gi tr thng s
chnh sch ti u s dng trong m hnh nn kinh t m n gin vi gi chm thay
i (sticky prices). Du hiu v ln ph hp vi gii thch theo quy tc thc
nghim c xut bi Obstfeld v Rogoff, v c h0 v h0 + h1 u nh hn khng.
Do vy, mt s tng t gi 10% lm ct gim li sut 3.7%, c ko theo bi mt s
b p 1.7%, ng rng phn ng di hn li sut gim 2%. Phn ng m ca li sut
c t tn l m hnh Ball (Balls model) bi v t gi tng c hiu ng ngc li
i vi tng cu; s tng gi lm hng ha nc ngoi r hn v hng ha trong nc
t hn, do vy lm gim xut khu. S ct gim li sut lm gim bt hiu ng
ngc li ny.
S b p li sut mt phn l bi v tc ng tr ca s gia tng t gi i vi
lm pht. Lm pht c o lng l thp tm thi bi v s tng t gi, tuy nhin, bi
v s gim trong lm pht l ngn hn, iu ny khng thch hp cho ngn hng trung
ng ni lng tin t bi v lm pht s thp hn.
S dng mt m hnh khc vi cc tc nhn hng ti tng lai (forward-
looking agent) v nhiu hn cc nhn t v m hon ho, Svensson (2000) xem xt
quy tc chnh sch tng t nh Ball (1999). Svensson tm ra cc thng s h0 = -0.45
v h1 = 0.45. M phng ca Svensson (2000) ch ra rng quy tc ny lm gim lch
chun ca lm pht t 2.1 xung cn 1.8%; tuy nhin, n cng lm gia tng phng
sai ca sn lng t 1.7 ln 1.8%. V vy, quy tc chnh sch, m phn ng trc t
gi hi oi theo cch ny, c th ph hng output performance.
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Cui cng, xem xt nghin cu th 3 ca dng quy tc chnh sch tin t vi
mt m hnh khc vi mt s vn dng khc. Theo Taylor (1999b), tc gi xem xt
quy tc chnh sch tin t m c dng ging nh ca Ball and Svensson. Cc h s h0
= -0.25 v h1 = 0.15 v y l mt ng c cho quy tc chnh sch tin t cho ngn
hng trung ng Chu u (the European Central Bank - ECB). T gi hi oi et l t
gi dollar euro. Do vy, s gim gi 10% ca ng EURO so vi ng USD to ra
s gia tng 0.1 im phn trm (10%) trong li sut mc tiu ca ECB. Thy rng cc
h s ny nh hn so vi cc h s trong nghin cu ca Ball.
Gii thch cc kt qu tm c:
Quy lut chnh sch vi cc thng s c thit lp bng khng khng c phn
ng trc tip ca li sut trc t gi hi hoi, n c mt phn ng gin tip ca li
sut trc t gi hi oi. D thy iu ny, gi s thng s h bng 0, do , li sut
s ch phn ng trc lm pht v sn lng thc. Nhng, bi v quy lut chnh sch,
chng ta c th k vng rng nu lm pht hoc GDP thc gia tng hoc st gim
trong tng lai sau li sut cng s tng hoc gim trong tng lai. c tnh ca
quy tc chnh sch l a ra nhng k hoch d on m s c s dng trong nhng
giai on tng lai.
Kt lun:
Mt vn quan trng v vn cn cha n nh trong chnh sch tin t ti cc
nn kinh t m l bao nhiu trong phn ng ca li sut nn c c trc t gi hi
oi trong c ch tin t ca t gi hi oi linh hot, lm pht mc tiu, v quy tc
chnh sch tin t. cc nghin cu n ngy hm nay ch bo rng quy tc chnh sch
tin t m phn ng trc tip trc t gi hi oi- cng nh l trc lm pht v sn
lng khng lm tt hn so vi lm pht v sn lng cn bng, v thng lm xu
hn, hn so vi quy tc chnh sch m khng phn ng trc tip ti t gi hi oi.
Bi nghin cu ny c gng gii thch cho kt qu tm ra bng cch khng nh
hiu ng gin tip ca t gi hi oi ln li sut. hiu ng gin tip ny tn ti thm
ch nu ngn hng trung ng thc thi quy tc chnh sch m khng c hiu ng t gi
hi oi trc tip. Tnh (qun tnh inertia) kt hp vi cc k vng hp l dn n