{"id":26834,"date":"2023-12-07T03:09:42","date_gmt":"2023-12-07T03:09:42","guid":{"rendered":"https:\/\/masterskills.org\/blog\/duong-ngan-sach-budget-line-trong-kinh-te-vi-mo-la-gi.html"},"modified":"2023-12-22T14:39:00","modified_gmt":"2023-12-22T07:39:00","slug":"duong-ngan-sach-budget-line-trong-kinh-te-vi-mo-la-gi","status":"publish","type":"post","link":"https:\/\/masterskills.org\/blog\/duong-ngan-sach-budget-line-trong-kinh-te-vi-mo-la-gi.html","title":{"rendered":"\u0110\u01b0\u1eddng ng\u00e2n s\u00e1ch (Budget line) trong kinh t\u1ebf vi m\u00f4 l\u00e0 g\u00ec?"},"content":{"rendered":"
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H\u00ecnh minh h\u1ecda (Ngu\u1ed3n: khanacademy)<\/p>\n<\/div>\n<\/div>\n

\u0110\u01b0\u1eddng ng\u00e2n s\u00e1ch<\/font><\/h2>\n

Kh\u00e1i ni\u1ec7m\u00a0<\/b><\/p>\n

\u0110\u01b0\u1eddng ng\u00e2n s\u00e1ch<\/b> trong ti\u1ebfng Anh g\u1ecdi l\u00e0: Budget line.<\/b><\/p>\n

Tr\u01b0\u1edbc khi \u0111i v\u00e0o kh\u00e1i ni\u1ec7m ta gi\u1ea3 s\u1eed nh\u01b0 sau:<\/p>\n

Gi\u1ea3 s\u1eed ng\u01b0\u1eddi ti\u00eau d\u00f9ng c\u00f3 m\u1ed9t m\u1ee9c thu nh\u1eadp I \u0111\u01b0\u1ee3c d\u00f9ng \u0111\u1ec3 chi ti\u00eau, mua s\u1eafm c\u00e1c h\u00e0ng h\u00f3a X v\u00e0 Y trong m\u1ed9t kho\u1ea3ng th\u1eddi gian nh\u1ea5t \u0111\u1ecbnh.\u00a0<\/p>\n

\u0110\u1ec3 \u0111\u01a1n gi\u1ea3n h\u00f3a, ta c\u0169ng gi\u1ea3 s\u1eed r\u1eb1ng, ng\u01b0\u1eddi ti\u00eau d\u00f9ng n\u00e0y kh\u00f4ng \u0111\u1ec3 d\u00e0nh, do \u0111\u00f3, thu nh\u1eadp I s\u1ebd \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng h\u1ebft cho m\u1ee5c ti\u00eau t\u1ed1i \u0111a h\u00f3a \u0111\u1ed9 th\u1ecfa d\u1ee5ng c\u1ee7a anh ta (hay ch\u1ecb ta).\u00a0<\/p>\n

Trong \u0111i\u1ec1u ki\u1ec7n \u0111\u00f3, m\u1ee9c thu nh\u1eadp I n\u00f3i tr\u00ean \u0111\u00e3 t\u1ea1o ra m\u1ed9t s\u1ef1 gi\u1edbi h\u1ea1n \u0111\u1ed1i v\u1edbi kh\u1ea3 n\u0103ng mua s\u1eafm c\u00e1c gi\u1ecf h\u00e0ng h\u00f3a c\u1ee7a ng\u01b0\u1eddi ti\u00eau d\u00f9ng. Anh ta (hay ch\u1ecb ta) kh\u00f4ng th\u1ec3 chi ti\u00eau cho c\u00e1c h\u00e0ng h\u00f3a v\u01b0\u1ee3t qu\u00e1 m\u1ee9c thu nh\u1eadp I.\u00a0<\/p>\n

Tuy nhi\u00ean, kh\u1ed1i l\u01b0\u1ee3ng c\u00e1c h\u00e0ng h\u00f3a X, Y m\u00e0 anh ta (hay ch\u1ecb ta) c\u00f3 th\u1ec3 mua \u0111\u01b0\u1ee3c kh\u00f4ng ch\u1ec9 t\u00f9y thu\u1ed9c v\u00e0o m\u1ee9c thu nh\u1eadp I. Ch\u00fang c\u00f2n ph\u1ee5 thu\u1ed9c v\u00e0o gi\u00e1 c\u1ea3 c\u1ee7a c\u00e1c h\u00e0ng h\u00f3a n\u00e0y. G\u1ecdi PX, PY\u00a0l\u1ea7n l\u01b0\u1ee3t l\u00e0 gi\u00e1 c\u1ea3 th\u1ecb tr\u01b0\u1eddng c\u1ee7a c\u00e1c h\u00e0ng h\u00f3a X v\u00e0 Y.\u00a0<\/p>\n

Khi mua m\u1ed9t kh\u1ed1i l\u01b0\u1ee3ng x h\u00e0ng h\u00f3a X, s\u1ed1 l\u01b0\u1ee3ng ti\u1ec1n c\u1ea7n \u0111\u1ec3 chi tr\u1ea3 l\u00e0 x.PX. Khi mua m\u1ed9t kh\u1ed1i l\u01b0\u1ee3ng y v\u1ec1 h\u00e0ng h\u00f3a Y, s\u1ed1 ti\u1ec1n ng\u01b0\u1eddi ti\u00eau d\u00f9ng ph\u1ea3i b\u1ecf ra l\u00e0 y.PY. V\u1eady m\u1ecdi gi\u1ecf h\u00e0ng h\u00f3a (x,y) m\u00e0 ng\u01b0\u1eddi ti\u00eau d\u00f9ng c\u00f3 th\u1ec3 mua s\u1eafm \u0111\u01b0\u1ee3c ph\u1ea3i th\u1ecfa m\u00e3n \u0111i\u1ec1u ki\u1ec7n sau:<\/p>\n

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B\u1ea5t \u0111\u1eb3ng th\u1ee9c (0) th\u1ec3 hi\u1ec7n s\u1ef1 r\u00e0ng bu\u1ed9c ng\u00e2n s\u00e1ch \u0111\u1ed1i v\u1edbi ng\u01b0\u1eddi ti\u00eau d\u00f9ng. Anh ta (hay ch\u1ecb ta) ch\u1ec9 c\u00f3 th\u1ec3 mua \u0111\u01b0\u1ee3c nh\u1eefng gi\u1ecf h\u00e0ng h\u00f3a nh\u1ea5t \u0111\u1ecbnh trong mi\u1ec1n r\u00e0ng bu\u1ed9c m\u00e0 b\u1ea5t \u0111\u1eb3ng th\u1ee9c (0) ch\u1ec9 ra.\u00a0<\/p>\n

Khi gi\u1ecf h\u00e0ng h\u00f3a (x,y) kh\u00f4ng th\u1ecfa m\u00e3n b\u1ea5t \u0111\u1eb3ng th\u1ee9c (0), t\u1ee9c x.PX + y.PY > I, n\u00f3 c\u00f3 th\u1ec3 l\u00e0 gi\u1ecf h\u00e0ng h\u00f3a \u0111\u00e1ng mong mu\u1ed1n \u0111\u1ed1i v\u1edbi ng\u01b0\u1eddi ti\u00eau d\u00f9ng (v\u1ec1 m\u1eb7t s\u1edf th\u00edch), song n\u00f3 l\u1ea1i l\u00e0 gi\u1ecf h\u00e0ng h\u00f3a kh\u00f4ng kh\u1ea3 thi \u2013 ng\u01b0\u1eddi ti\u00eau d\u00f9ng kh\u00f4ng th\u1ec3 mua \u0111\u01b0\u1ee3c trong kh\u1ea3 n\u0103ng ti\u1ec1n b\u1ea1c c\u1ee7a m\u00ecnh (r\u00e0ng bu\u1ed9c v\u1ec1 m\u1eb7t ng\u00e2n s\u00e1ch).\u00a0<\/p>\n

V\u1ec1 ph\u01b0\u01a1ng di\u1ec7n h\u00ecnh h\u1ecdc, c\u00f3 th\u1ec3 bi\u1ec3u th\u1ecb mi\u1ec1n r\u00e0ng bu\u1ed9c ng\u00e2n s\u00e1ch \u0111\u1ed1i v\u1edbi ng\u01b0\u1eddi ti\u00eau d\u00f9ng b\u1eb1ng tam gi\u00e1c AOB tr\u00ean h\u00ecnh 1. M\u1ecdi \u0111i\u1ec3m n\u1eb1m trong h\u00ecnh tam gi\u00e1c AOB v\u00e0 n\u1eb1m tr\u00ean c\u00e1c c\u1ea1nh c\u1ee7a n\u00f3, \u0111\u1ec1u th\u1ecfa m\u00e3n b\u1ea5t \u0111\u1eb3ng th\u1ee9c (0), n\u00ean \u0111\u1ec1u l\u00e0 nh\u1eefng \u0111i\u1ec3m kh\u1ea3 thi.\u00a0<\/p>\n

Nh\u1eefng \u0111i\u1ec3m n\u1eb1m b\u00ean ngo\u00e0i tam gi\u00e1c n\u00e0y l\u00e0 nh\u1eefng \u0111i\u1ec3m kh\u00f4ng kh\u1ea3 thi \u2013 nh\u1eefng \u0111i\u1ec3m th\u1ec3 hi\u1ec7n c\u00e1c gi\u1ecf h\u00e0ng h\u00f3a m\u00e0 ng\u01b0\u1eddi ti\u00eau d\u00f9ng kh\u00f4ng th\u1ec3 mua \u0111\u01b0\u1ee3c.<\/p>\n

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H\u00ecnh 1: Mi\u1ec1n r\u00e0ng bu\u1ed9c ng\u00e2n s\u00e1ch<\/p>\n<\/div>\n<\/div>\n

Kh\u00e1i ni\u1ec7m \u0111\u01b0\u1eddng ng\u00e2n s\u00e1ch<\/b><\/p>\n

\u0110\u01b0\u1eddng ng\u00e2n s\u00e1ch<\/b> m\u00f4 t\u1ea3 c\u00e1c gi\u1ecf h\u00e0ng h\u00f3a (x,y) t\u1ed1i \u0111a m\u00e0 ng\u01b0\u1eddi ti\u00eau d\u00f9ng c\u00f3 th\u1ec3 mua \u0111\u01b0\u1ee3c.\u00a0<\/p>\n

\u0110\u01b0\u1eddng ng\u00e2n s\u00e1ch cho ch\u00fang ta bi\u1ebft s\u1ed1 l\u01b0\u1ee3ng h\u00e0ng h\u00f3a Y t\u1ed1i \u0111a m\u00e0 ng\u01b0\u1eddi ti\u00eau d\u00f9ng c\u00f3 th\u1ec3 mua \u0111\u01b0\u1ee3c khi \u0111\u00e3 mua m\u1ed9t l\u01b0\u1ee3ng h\u00e0ng h\u00f3a X nh\u1ea5t \u0111\u1ecbnh, hay s\u1ed1 l\u01b0\u1ee3ng h\u00e0ng h\u00f3a X t\u1ed1i \u0111a m\u00e0 ng\u01b0\u1eddi ti\u00eau d\u00f9ng c\u00f3 th\u1ec3 mua\u00a0\u0111\u01b0\u1ee3c khi \u0111\u00e3 mua m\u1ed9t l\u01b0\u1ee3ng h\u00e0ng h\u00f3a Y nh\u1ea5t \u0111\u1ecbnh.\u00a0<\/p>\n

Khi \u0111\u00e3 mua m\u1ed9t l\u01b0\u1ee3ng x nh\u1ea5t \u0111\u1ecbnh, s\u1ed1 l\u01b0\u1ee3ng y t\u1ed1i \u0111a c\u00f3 th\u1ec3 mua \u0111\u01b0\u1ee3c ch\u00ednh l\u00e0 l\u01b0\u1ee3ng thu nh\u1eadp I c\u00f2n l\u1ea1i sau khi \u0111\u00e3 mua x chia cho m\u1ee9c gi\u00e1 PY:\u00a0<\/p>\n

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T\u1eadp h\u1ee3p c\u00e1c gi\u1ecf h\u00e0ng h\u00f3a (x,y) t\u1ed1i \u0111a \u1edf \u0111\u00e2y ph\u1ea3i th\u1ecfa m\u00e3n \u0111\u1eb3ng th\u1ee9c hay ph\u01b0\u01a1ng tr\u00ecnh:<\/p>\n

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D\u1ec5 d\u00e0ng nh\u1eadn ra r\u1eb1ng (1) v\u00e0 (2) ho\u00e0n to\u00e0n t\u01b0\u01a1ng \u0111\u01b0\u01a1ng nhau. Ph\u01b0\u01a1ng tr\u00ecnh (1) hay (2) ch\u00ednh l\u00e0 ph\u01b0\u01a1ng tr\u00ecnh \u0111\u01b0\u1eddng ng\u00e2n s\u00e1ch.\u00a0<\/p>\n

V\u00ec ph\u01b0\u01a1ng tr\u00ecnh (1) l\u00e0 m\u1ed9t ph\u01b0\u01a1ng tr\u00ecnh tuy\u1ebfn t\u00ednh n\u00ean \u0111\u01b0\u1eddng ng\u00e2n s\u00e1ch l\u00e0 m\u1ed9t \u0111\u01b0\u1eddng th\u1eb3ng. Ch\u00fa \u00fd r\u1eb1ng ch\u00fang ta bi\u1ec3u th\u1ecb x, y l\u00e0 kh\u1ed1i l\u01b0\u1ee3ng c\u1ee7a c\u00e1c h\u00e0ng h\u00f3a X, Y, n\u00ean \u0111i\u1ec1u \u0111\u00f3 gi\u1ea3 \u0111\u1ecbnh ng\u1ea7m r\u1eb1ng x v\u00e0 y l\u00e0 nh\u1eefng s\u1ed1 kh\u00f4ng \u00e2m.\u00a0<\/p>\n

C\u00f3 th\u1ec3 kh\u00f4ng kh\u00f3 kh\u0103n \u0111\u1ec3 nh\u1eadn ra r\u1eb1ng, \u0111\u01b0\u1eddng AB tr\u00ean h\u00ecnh 1 ch\u00ednh l\u00e0 \u0111\u01b0\u1eddng ng\u00e2n s\u00e1ch g\u1eafn li\u1ec1n v\u1edbi \u0111i\u1ec1u ki\u1ec7n v\u1ec1 thu nh\u1eadp v\u00e0 gi\u00e1 c\u1ea3 \u0111\u00e3 bi\u1ebft.\u00a0<\/p>\n

\u0110i\u1ec3m m\u00fat A tr\u00ean tr\u1ee5c tung bi\u1ec3u th\u1ecb l\u01b0\u1ee3ng h\u00e0ng h\u00f3a Y t\u1ed1i \u0111a c\u00f3 th\u1ec3 mua \u0111\u01b0\u1ee3c khi ng\u01b0\u1eddi ti\u00eau d\u00f9ng kh\u00f4ng mua m\u1ed9t \u0111\u01a1n v\u1ecb h\u00e0ng h\u00f3a X n\u00e0o. Tung \u0111\u1ed9 c\u1ee7a n\u00f3 c\u00f3 gi\u00e1 tr\u1ecb b\u1eb1ng I\/PY.<\/p>\n

T\u01b0\u01a1ng t\u1ef1, \u0111i\u1ec3m m\u00fat B tr\u00ean tr\u1ee5c ho\u00e0nh bi\u1ec3u th\u1ecb l\u01b0\u1ee3ng h\u00e0ng h\u00f3a X t\u1ed1i \u0111a c\u00f3 th\u1ec3 mua \u0111\u01b0\u1ee3c khi ng\u01b0\u1eddi ti\u00eau d\u00f9ng kh\u00f4ng mua m\u1ed9t \u0111\u01a1n v\u1ecb h\u00e0ng h\u00f3a Y n\u00e0o. Ho\u00e0nh \u0111\u1ed9 c\u1ee7a n\u00f3 c\u00f3 gi\u00e1 tr\u1ecb b\u1eb1ng I\/PX.\u00a0<\/p>\n

Nh\u1eefng \u0111i\u1ec3m n\u1eb1m tr\u00ean \u0111\u01b0\u1eddng ng\u00e2n s\u00e1ch AB \u0111\u1ec1u l\u00e0 nh\u1eefng \u0111i\u1ec3m kh\u1ea3 thi trong \u0111i\u1ec1u ki\u1ec7n thu nh\u1eadp I \u0111\u01b0\u1ee3c chi ti\u00eau h\u1ebft. Nh\u1eefng \u0111i\u1ec3m kh\u1ea3 thi n\u1eb1m trong mi\u1ec1n r\u00e0ng bu\u1ed9c ng\u00e2n s\u00e1ch nh\u01b0ng kh\u00f4ng n\u1eb1m tr\u00ean \u0111\u01b0\u1eddng ng\u00e2n s\u00e1ch \u0111\u1ec1u bi\u1ec3u th\u1ecb c\u00e1c tr\u01b0\u1eddng h\u1ee3p thu nh\u1eadp hay ng\u00e2n s\u00e1ch I kh\u00f4ng \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng h\u1ebft.\u00a0<\/p>\n

V\u1ecb tr\u00ed c\u1ee7a \u0111\u01b0\u1eddng ng\u00e2n s\u00e1ch ph\u1ee5 thu\u1ed9c v\u00e0o m\u1ee9c thu nh\u1eadp I v\u00e0 c\u00e1c m\u1ee9c gi\u00e1 c\u1ee7a c\u00e1c h\u00e0ng h\u00f3a X,Y. \u0110\u1ed9 d\u1ed1c c\u1ee7a \u0111\u01b0\u1eddng ng\u00e2n s\u00e1ch ph\u1ee5 thu\u1ed9c v\u00e0o m\u1ee9c gi\u00e1 t\u01b0\u01a1ng \u0111\u1ed1i c\u1ee7a hai h\u00e0ng h\u00f3a n\u00e0y v\u00e0 \u0111o b\u1eb1ng (- PX\/PY)<\/p>\n

(T\u00e0i li\u1ec7u tham kh\u1ea3o: Gi\u00e1o tr\u00ecnh Kinh t\u1ebf Vi m\u00f4, PGS.TS. Ph\u00ed M\u1ea1nh H\u1ed3ng, NXB \u0110\u1ea1i h\u1ecdc Qu\u1ed1c Gia H\u00e0 N\u1ed9i)<\/i><\/p>\n<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"

\n \u0110\u01b0\u1eddng ng\u00e2n s\u00e1ch (ti\u1ebfng Anh: Budget line) l\u00e0 m\u1ed9t c\u00f4ng c\u1ee5 \u0111\u1ed3 th\u1ecb bi\u1ec3u di\u1ec5n l\u1ef1a ch\u1ecdn c\u1ee7a ng\u01b0\u1eddi ti\u00eau d\u00f9ng.\n <\/div>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[414],"tags":[],"_links":{"self":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/posts\/26834"}],"collection":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/comments?post=26834"}],"version-history":[{"count":0,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/posts\/26834\/revisions"}],"wp:attachment":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/media?parent=26834"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/categories?post=26834"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/tags?post=26834"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}