Tiểu luận môn tài chính tiền tệ Lý thuyết về bộ ba bất khả thi

Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn

TRƯỜNG ĐẠI HỌC KINH TẾ THÀNH PHỐ HỒ CHÍ MINH
KHOA TÀI CHÍNH NHÀ NƯỚC
  
 Tài chính Tiền tệ
Đề tài:
LÝ THUYẾT VỀ BỘ BA BẤT KHẢ THI
Giảng viên hướng dẫn : ThS. Trương Minh Tuấn
Nhóm sinh viên thực hiện : Nhóm 05
Lớp : VB16BQT01
Khoá : 16B
Thành phố Hồ Chí Minh
Tháng 03 năm 2014
Lớp: VB16BQT01 - Nhóm 05 1
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
DANH SÁCH NHÓM THUYẾT TRÌNH
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Lớp: VB16BQT01 - Nhóm 05 2
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
NHẬN XÉT CỦA GIẢNG VIÊN
Nhận xét Điểm
Lớp: VB16BQT01 - Nhóm 05 3
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
MỤC LỤC
Chương 1. Giới thiệu chung về bộ ba bất khả thiRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR
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 R R5%\%53]^_]`0*)*%0W`J*%a%S)*%'0Z%b6.*%a%S)*%'J
'c39d*)**%XU2'e)RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR
 R R R%a%S)*%'0Z%/)`0*%a%S)*%'J'c39d*%XU2'e)*8UG%RRRRRRRRRRRRRRRRR
 R R"R%a%S)*%'0Z%/)`0*%a%S)*%'J'c39d*%XU2'e)%%/f'RRRRRRRRRRRRRRR

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 RR%CX''6)*h(2*V6i6`06j6RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR#
 RDR%CX''k3clm']'(6%]3(/?C-/'%]SSn RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRA
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"RR?2%-'0*%a%l'p3/%b63q`8nRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR #
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DR R%9d*U/RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR 
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Chương 2: Thực tiễn áp dụng bộ ba bất khả thiRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR""
R2464Y'Z%['%h*)*9d*RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR""
 R R2464Y'Z%['%h%OsRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR""
 R"R2464Y'Z%['%h5tRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR""
 RR2464Y'Z%['%h(78*RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR""
"R)*`YUJ'%p*'@hc'I6RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR""
"R Rp6'Q*V6f-%)'RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR""
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"RR%G'(9:*%kZ%/)'&'38*RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR"
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Lớp: VB16BQT01 - Nhóm 05 4

Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
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Chương 3: Kết luậnRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR
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Lớp: VB16BQT01 - Nhóm 05 5
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
CHƯƠNG 1. GIỚI THIỆU CHUNG VỀ BỘ BA BẤT KHẢ THI
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'%0%~%\%4Y'Z%['%•RTheo lý thuyết này, một quốc gia không thể đồng thời
đạt được cả ba mục tiêu: chính sách tiền tệ độc lập, tỷ giá cố định, và tự do hoá
dòng vốn.
1. Lịch sử ra đời của lý thuyết bộ ba bất khả thi:
1.1. Mô hình Mundell – Fleming và các hàm ý về chính sách tài khóa, chính
sách tiền tệ dưới các chế độ tỷ giá:
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'a%UX')*U2*V6*)*O'%6%'/)ROCU9,*j]0UZ%hU=*%/W
'%CX'42464Y'Z%['%R5%\%53]€_]*%1(6Sp%c•[%6CZ%
%c•[*V6*%a%S)*%'J'c`0*%a%S)*%'0Z%/)39d*)**%XU2'e)Z%)*
%6R
1.1.1. Chính sách tài khoá và chính sách tiền tệ dưới chế độ tỷ giá cố định:
='M.%\%53]€_]*%1(6(H.*%a%S)*%'J'c`0*%a%
S)*%'0Z%/)*b'%0'%6CU+*)*'(f'%)*V6*)*O'%6%'/)R‚'U='f
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'fUR
Hình 1.1: Mô hình IS-LM của Mundell-Fleming với tỷ giá cố định
Lớp: VB16BQT01 - Nhóm 05 6
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
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39%6C'%O%&'S†0'Q%/F*[*'J*V6JZ%'X`\O%0(
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9d*RI%H'()%%|')*U2*V6`c*64)/f'cUXf-%)''(/9d*.
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-%['X%0%*)N0~*%a%S)*%`%c%/)•.'k*0O%0(9<S†
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U4H9,2'c[UZ%O%0(9<4)/f'cU3C'(\*)
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%0(9<S†4)*)**%kZ%/)'(M'%G'(9:hU%'9,2'cU9,*

36/f'c'(9d*UbR
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%/).'%\S6Ub'Y'CX(H.*%a%S)*%'0Z%/)'(hM%c•[%<*%a%S)*%'J
'cR‚'U='fUrlHình 1.1n.2'Sph(2*%a%S)*%'J'cS†*%CU9:
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'Q'(/2''%:6‚S†•6CfU*O4Hi‰R/Ub.*%a%S)*%'J'c
Z%%c•[%/0'/0U06'QS[9,•8*6RI9,*f.[UG%
(H.4‚'U='fUr.*%'6'%p*%c2'*%a%S)*%'0Z%b6h(2.U9:
3G*%*%CS6….3‡'d2'*)*O'%6%'/)'%F39'fURB%
Lớp: VB16BQT01 - Nhóm 05 7
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
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'JZ%Z%*b`%c%/)4+S*%/Sph(2*%a%S)*%'0Z%/)46U=R
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•[*6/%<`0*%a%S)*%'J'cZ%c•[%<R
1.1.2. Chính sách tài khoá và chính sách tiền tệ dưới chế độ tỷ giá linh
hoạt:
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-%=6/%6*V6U9:*/.L5.$Š`0[UG%*b2'Sph(2*%a%
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Lớp: VB16BQT01 - Nhóm 05 8
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Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
Hình 1.2: Mô hình IS-LM của Mundell-Fleming với tỷ giá linh hoạt.
1.2. Thuyết bộ ba bất khả thi của GS. Robert Mundell và Marcuss Fleing:
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Hình 1.3. Tam giác bộ ba bất khả thi
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Lớp: VB16BQT01 - Nhóm 05 9
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
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Chính
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BS/)'`8 B% b b
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Bảng 1.1. Nguyên lý của bộ ba bất khả thi
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Uf'U9,*UK'%:*[46&*'MR
1.3.Thuyết tam giác mở rộng của Yigang và Tangxian:
i6`06j6l"!! n'X-'&*-%)''(W'%CX'42464Y'Z%['%*V6
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Lớp: VB16BQT01 - Nhóm 05 10
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
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Lớp: VB16BQT01 - Nhóm 05 11
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Lớp: VB16BQT01 - Nhóm 05 12
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
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1.4. Thuyết tứ diện (A tetrahedron Hypothesis):
* Cơ chế tỷ giá trung gian - nền tảng của thuyết tam giác mở rộng và
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Lớp: VB16BQT01 - Nhóm 05 13
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
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* Thuyết tứ diện:
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Lớp: VB16BQT01 - Nhóm 05 14
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
Hình 1.5. Thuyết tứ diện
(/Hình 1.5.*%'6*b2''k3cUJRF'F'39d'9,'(9*%/
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Lớp: VB16BQT01 - Nhóm 05 15
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
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Lớp: VB16BQT01 - Nhóm 05 16
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
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Lớp: VB16BQT01 - Nhóm 05 17
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
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Bảng 1.3. Sự lựa chọn cơ chế tỷ giá theo thuyết tứ diện
2.Khái niệm chung về bộ ba bất khả thi:
2.1. Chính sách tiền tệ độc lập:
Lớp: VB16BQT01 - Nhóm 05 18
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
%a%S)*%'J'cU2*-0%|*%a%S)*%0%09d*'%p*%c%H
&*Ua*%UJ'X'Z%'X.%9Z%•6'OUX%|*%a%S)*%.UX'1)%6C
'Q[.%6C*)*4XS8`ˆZ%)*R
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'J'cU'%p*%c*%a%S)*%-%[*%ZPZ%'XR%u%fXJZ%'X*b3Y
%c-%)''(b.*%a%-%VS†'QvSY'%/F*'%‚'*%F'*'J`09,*fR
(/*)*'(9:%,-0C*%a%-%VZ%•6'OUX'e)'Q%6C[`0*)*
4XS8Z%'X`ˆZ%)*R%a%`\SpU2*-'J'c0C0%J%0Z%'X'
(H*%S†-JZ%'X'Q'(9h+UG%%<RC%MU2*-'J'c•)
k**b'%02'*)*dU*%a%-%Vf3&'%p*%c*)**%X9,*'Q'(9h
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'J}C*<f-%)'*6/Rb0*%96ZU2*-'J'c•)k**bZ%[Q0
*%/*%a%-%V'J'c%b6*%'M*%a%-%V4H*)*%-%)'%0%'J'(6'([*%/
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2.2. Ổn định tỷ giá:
oUG%'e)-'f/(6*)]/36%%ˆ6U*%a%-%V'X%0%*)*4c
-%)-+UG%)*[R)]/0C0*%/%'%k**V6%0U='9U8`d(V(/*V6

JZ%'X[U.0'Q'%MJ'*V6**%`)/UK2'cRY'*[
-0*%/'(9:U='9'8'MRC%M.'e)*8UG%%6C+UG%•)k*
*bF''()*V6bRe)•)+UG%0*%/*%a%-%VY'U2'**&U%Y-
'%&*)**S84M'(/`04M/03‡`0/JZ%'X
a3&.f-%)'*6/'(/9d*0'e)=%9*8UG%3@3‡UXC*<
%0%b6Y'Sp**f%'(6%'(M'%G'(9:'%Xd.%•[0jY'Z%}[`0
%-Z%}'QMRI/0(6.'a%•)*k%‚**V6'e)*qQ*[Z%*%/
%|%00*%a%S)*%ST3&**&*%a%S)*%-%%,-`d'%p*'X3@4X
*[JZ%'X.%Y'0Z%U6*b3Y%c4/4b'0S[
I%\*%'e)•)*k%‚**%u%|*bZ%[Q3‡UX4Y'+
'(/'Q'(9h.(V(/f-%)'*6/0*q3‡UX-%O4+S6Kp*`0'Q
'(9hZ%4J`|R
2.3. Hội nhập tài chính (tự do hóa dòng vốn):
L0`c**%/*)**%V'%U9,*'p3/*%CU+*)*'0S['0*%a%'(/9d*
'%0%'0S['0*%a%9d*/0`09,*f'%]/'e)%8U/)3/'%G'(9:•C
UG%R
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Lợi ích:
Lớp: VB16BQT01 - Nhóm 05 19
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
’?|%\%-•8*6'Q'(9h%6%%<`0-%O4+Kp*'8'
%<.-%0U='9U63f%b6U='9R
’%\% :f/(6U2p*-*%/*%a%-%V'X%0%%J*[*)*%`0
•['(G'8'%<U'%]/ZG-%|'%6CU+'„%2%-R
L,a*%d%Y'6f'„%2%-'0*%a%0'f/(6U2p*-*%/*%a%
-%V'X%0%%J*[*)*%`0•['(G'8'%<U'%]/ZG-%|'%6CU+'„%2
%-R
Hạn chế:?2%-'0*%a%*•U9,**%/0CM%O3‡UX4Y'+
Z%'X%|Q=UOCRq`8)'X-*%[C`0/JZ%'XU6-%=0‚
%f`06'a%U=*<R

3. Sự kết hợp của bộ ba bất khả thi:
3.1. Tỷ giá cố định và tiền tệ độc lập: U9,*ZX'%,-4H*)*%p6*%N'%G
'(9:`8Ub%6C*%a%-%V-%['%X'-ZS/)'`8%/0'/0RB%*bZ
S/)'`8.8M%c|6vSY'`0'e)S†4G-%)`–R
3.2. Tiền tệ độc lập và tự do vốn: U9,*ZX'%,-4H*)*%p6*%N*%XU2'e
)'%[•.`dp6*%N0C*%a%-%VlI?™nU9,*•CJ'p3/YUG%vSY'
%9U+f'e)-%[`%0%'%]/CM'‚**V6'%G'(9:R
3.3. Tự do vốn và tỷ giá cố định: U9,*ZX'%,-4H*)*%p6*%N*%XU2'e
)*8UG%%9-%['„4ŒU2*-'J'cRUJ0C*b%ˆ60*%a%-%VUvY'U
2'**&UJ*%1%vSY''(/9d*U2*-`dvSY'9d*/0R
4. Thước đo bộ ba bất khả thi:
4.1. Thước đo:
4.1.1. Độc lập tiền tệ (MI):
5k*U2U2*-'J'cU9,*U/4H%0%G*%U[/*V6k*'9<•6%0
Q*V6vSY'%0'%)|6•8*6Sh'f`0•8*6*<ShR%1S8k*U2U2*
-'J'cU9,*j)*UG%4H*'%k*

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
Lớp: VB16BQT01 - Nhóm 05 20
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
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Lớp: VB16BQT01 - Nhóm 05 21
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
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%J%9d*%CMSOZ%)*.*%u%f%9')*U2*V6*)*ZX'%,-*%a%S)*%UX
*)*4XS8Z%'X`ˆ.%6C%|'%6CU+*%a%S)*%S6Z%V%/[ž
4.2. Chứng minh:
4.2.1. Dùng mô hình tam giác đều:
?\% 0Sp%%N6`JCM'‚*%/f'U2*V642464Y'Z%['%R5•*f%
'%%c*%/*)*&*'M'8'%Y'.=9,'0*%a%S)*%'J'cU2* Sp+UG%
*V6'e).`0%2%-'0*%a%%/0'/0R8%G*%`d•*f%l%6C•&*
'Mn0*)***&*%a%S)*%'f*)*U1%R5&*'M%2%-'0*%a%U8%G*%`d

U1%ZS/)'`8Š&*'M+UG%'e)U+9,*`dU1%'%[•%/0'/0Š&*
'M*%a%S)*%'J'cU2*-U89,*`dU1%]%'J'cRY'ZP*F-&*
'M0/*•*b'%Uf'U9,*4h2'U1%H|6Ra3&.&*'M*%a%S)*%'J
'cU2*-`0'e)+UG%Uf'U9,*4hU1%ZS/)'`8%/0'/0R5&*'M*%a%
S)*%'J'cU2*-`0%2%-'0*%a%%/0'/0*b'%Z%['%`dU1%'%[•
%/0'/0R
8*.&*'M'e)+UG%`0%2%-'0*%a%Uf'U9,*4hU1%M
%'J'cR
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
Lớp: VB16BQT01 - Nhóm 05 22
BMŸS/)'`8
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn

%a%S)*%'J'cU2*-e)+UG%
?2%-'0*%a%%/0'/0
Tam giác bộ ba bất khả thi.
Nguyên lý của bộ ba bất khả thi:
q`8
9U2
%/0'/0
%a%
S)*%'J
'cU2*-
?c'%8
'e)*8
UG%
a3&
BS/)'`8 B% b b
(78*'(9d**2**[

*)*%'%)E•"!!#
LM%'J'c b Z% b ?KB/.ry
e)'%[+ *b *b B% I%'.Ž*
p6`0/4['b'‚''6*b'%'%YC(H2'•8*6Z%'%'%p*%c
UK'%:46&*'MRIXUf'U9,*&*'M3q`89U2%/0'/0`0%c
'%8'e)*8UG%'%\%09d*-%['%p*%cZX%/f*%ZS/)'`8.`0%9`C
'%\3q`8Z%'%*%[C`0/JZ%'X2'*)*%'p3/U9,*.%ˆ60Z%'%p*
%cU9,*&*'M3q`89U2'p3/R9<'p.2'Z%'%p*%cU9,*&*
'M%c'%8'e)*8UG%`03q`89U2`0/JZ%'X'p3/'%\Z%'%
'%p*%cU9,*&*'M*%a%S)*%'J'cU2*-`\-%['%p*%c]%'J'c
lM%'J'c*b'%U9,*%\%38%9`c**)*•8*6]%*)*
*%a%S)*%'J'c8%9Z%8ry%c6CnR0*qf.U*bU9,*&*'M*%a%
S)*%'J'cU2*-`0'p3/%b63q`8'%\-%[%CS%%c'%8'e)*8UG%R0
Z%Ub'%\-%['%p*%c4c-%)-U'e)'%[+R
Lớp: VB16BQT01 - Nhóm 05 23
%6Ÿ•%/0'/0
LM%'J'Ṃ
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
4.2.2. Dùng đồ thị (R, Y):
(M•%\%`†`dZW%c*)*U9:%9S6
BP'-%,-*)*'+%,-|6S[9,`0vSY'0'fUb*bSp*O4H*)
*O'%6%'/)R
LM U9:43@2''-%,-*)*U*O4H'(O'%G'(9:'c'cR
L`050%*=|'JF'*V6*)%O`0*'J*V6*<•6•[W
'J'c*V6%09d*R
r vSY'R
Y U9:'+*=R
ISU9:4'%G'-%,-*)*k*vSY'`0'%%-*O4H'%G'(9:
%0%b6`ˆR
I 0U='9

S 'X'ZcR
Ổn định tỷ giá và độc lập tiền tệ :
Thị trường vốn đóng.
wY'-%)''„m'%p*%c*%a%S)*%'J'ch(203G*%*%CL5UX
L5 R
L5 *‚''f'%\*bg'%Y-%<.*b ¡i!0*%/SY'Z%}(qIw
[0Y'*O4H'e)RIX%09d**%/%2%-'0*%a%0*%/)-p*
*0dU8`d*8UG%'e)ƒ¡%2%-'0*%a%S†Z%'K'fR
Độc lập tiền tệ và hội nhập tài chính:
w''fUmX%09d*'%p*%c*%a%S)*%'J'ch(2'%\U9:
L53G*%*%CjY''%0%L5 R9:L5 *‚''f*b('%Y-03q`8
3G*%*%C(69d*/0`0'fUb*bk*S[9,i d%<k*S[9,i!
Lớp: VB16BQT01 - Nhóm 05 24
Lý thuyết về bộ ba bất khả thi GVHD: ThS. Trương Minh Tuấn
0*%/SY'Z%}(q[ƒ¡*/f'c[.*=/f'c'Qƒ¡Z%'%
+UG%'e)R
Tỷ giá thả
nˆi.
Ổn định tỷ giá và hội nhập tài chính
j''fUm'%p*%c*%a%S)*%h(2'J'cU9:L53G*%*%CUX
L5 R
L5 *‚''f*0C'f*b('%Y jY'Z%}(q[lIwn0'e)
4XU+.%09d*-%[4U‚-Z%/[/f'c0C4H*)*%4</f'c`0/'%G
'(9:ƒ¡0L5 3G*%*%CUXL5ƒ¡*%a%S)*%'J'c`')*3&R
Tỷ giá cố định
Lớp: VB16BQT01 - Nhóm 05 25