{"id":23853,"date":"2023-12-06T08:57:03","date_gmt":"2023-12-06T08:57:03","guid":{"rendered":"https:\/\/masterskills.org\/blog\/ham-ich-loi-cong-tinh-additive-utility-function-la-gi.html"},"modified":"2023-12-22T09:09:04","modified_gmt":"2023-12-22T02:09:04","slug":"ham-ich-loi-cong-tinh-additive-utility-function-la-gi","status":"publish","type":"post","link":"https:\/\/masterskills.org\/blog\/ham-ich-loi-cong-tinh-additive-utility-function-la-gi.html","title":{"rendered":"H\u00e0m \u00edch l\u1ee3i c\u1ed9ng t\u00ednh (Additive utility function) l\u00e0 g\u00ec?"},"content":{"rendered":"
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H\u00ecnh minh h\u1ecda<\/p>\n<\/figcaption><\/figure>\n

H\u00e0m \u00edch l\u1ee3i c\u1ed9ng t\u00ednh (Additive utility function)<\/font><\/font><\/h2>\n

\u0110\u1ecbnh ngh\u0129a<\/b><\/p>\n

H\u00e0m \u00edch l\u1ee3i c\u1ed9ng t\u00ednh<\/b> trong ti\u1ebfng Anh l\u00e0 Additive utility function<\/b>.\u00a0H\u00e0m \u00edch l\u1ee3i c\u1ed9ng t\u00ednh<\/i> l\u00e0 h\u00e0m \u00edch l\u1ee3i c\u00f3 d\u1ea1ng: U = Ua + Ub + Uc.<\/p>\n

Trong \u0111\u00f3:<\/p>\n

U l\u00e0 \u00edch l\u1ee3i<\/p>\n

Ua, Ub, Uc l\u1ea7n l\u01b0\u1ee3t l\u00e0 \u00edch l\u1ee3i c\u1ee7a c\u00e1c nh\u00f3m h\u00e0ng h\u00f3a a, b, c v\u00e0 c\u00e1c nh\u00f3m n\u00e0y kh\u00f4ng th\u1ec3 thay th\u1ec3 cho nhau.<\/p>\n

V\u00ec \u00edch l\u1ee3i c\u1ee7a h\u00e0ng h\u00f3a a kh\u00f4ng ph\u1ee5 thu\u1ed9c v\u00e0o c\u1ee7a b, n\u00ean \u00edch l\u1ee3i c\u1eadn bi\u00ean c\u1ee7a h\u00e0ng h\u00f3a a ch\u1ec9 ph\u1ee5 thu\u1ed9c v\u00e0o l\u01b0\u1ee3ng h\u00e0ng h\u00f3a a ch\u1ee9 kh\u00f4ng ph\u1ee5 thu\u1ed9c v\u00e0o h\u00e0ng h\u00f3a kh\u00e1c. Khi \u0111\u00f3, n\u1ebfu t\u1ea5t c\u1ea3 c\u00e1c h\u00e0ng h\u00f3a \u0111\u1ec1u c\u00f3 \u00edch l\u1ee3i c\u1eadn bi\u00ean gi\u1ea3m d\u1ea7n, th\u00ec \u0111\u01b0\u1eddng b\u00e0ng quan s\u1ebd c\u00f3 d\u1ea1ng l\u1ed3i so v\u1edbi \u0111i\u1ec3m g\u1ed1c, t\u1ee9c cong v\u00e0o ph\u00eda trong.<\/p>\n

T\u1ed5ng h\u1ee3p l\u1ea1i, ch\u00fang ta c\u00f3 th\u1ec3 n\u00f3i n\u1ebfu c\u00f3 h\u00e0m \u00edch l\u1ee3i c\u1ed9ng t\u00ednh v\u00e0 m\u1ecdi h\u00e0ng h\u00f3a \u0111\u1ec1u c\u00f3 \u00edch l\u1ee3i c\u1eadn bi\u00ean gi\u1ea3m d\u1ea7n, \u0111\u01b0\u1eddng b\u00e0ng quan s\u1ebd c\u00f3 d\u1ea1ng l\u1ed3i. \u0110\u1ec3 r\u00f5 r\u00e0ng h\u01a1n, h\u00e3y xem h\u00ecnh minh h\u1ecda ph\u00eda d\u01b0\u1edbi:<\/p>\n

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Ngu\u1ed3n: T\u1eeb \u0111i\u1ec3n Kinh t\u1ebf h\u1ecdc, NXB \u0110\u1ea1i h\u1ecdc Kinh t\u1ebf Qu\u1ed1c d\u00e2n<\/p>\n<\/figcaption><\/figure>\n

C\u00f3 \u0111\u01b0\u1eddng b\u00e0ng quan I1 li\u00ean quan \u0111\u1ebfn hai h\u00e0ng h\u00f3a X v\u00e0 Y. Xem x\u00e9t \u0111i\u1ec3m A tr\u00ean \u0111\u01b0\u1eddng b\u00e0ng quan v\u00e0 s\u1ef1 di chuy\u1ec3n \u0111\u1ebfn \u0111i\u1ec3m B. T\u1ea1i \u0111i\u1ec3m B, ch\u00fang ta c\u00f3 nhi\u1ec1u h\u00e0ng h\u00f3a X h\u01a1n v\u00e0 \u00edt h\u00e0ng h\u00f3a Y h\u01a1n.<\/p>\n

N\u1ebfu \u00edch l\u1ee3i c\u1eadn bi\u00ean c\u1ee7a X gi\u1ea3m d\u1ea7n v\u00e0 ch\u1ec9 ph\u1ee5 thu\u1ed9c v\u00e0o l\u01b0\u1ee3ng c\u1ee7a X, th\u00ec ch\u00fang ta bi\u1ebft r\u1eb1ng \u00edch l\u1ee3i c\u1eadn bi\u00ean c\u1ee7a X t\u1ea1i B ph\u1ea3i nh\u1ecf h\u01a1n so v\u1edbi \u0111i\u1ec3m A, ch\u1ec9 \u0111\u01a1n gi\u1ea3n v\u00ec t\u1ea1i A ng\u01b0\u1eddi ti\u00eau d\u00f9ng c\u00f3 nhi\u1ec1u h\u00e0ng h\u00f3a X h\u01a1n. V\u00ec t\u1ea1i A anh ta c\u00f3 \u00edt h\u00e0ng h\u00f3a Y h\u01a1n, n\u00ean \u00edch l\u1ee3i c\u1eadn bi\u00ean t\u1eeb Y m\u00e0 anh ta nh\u1eadn \u0111\u01b0\u1ee3c t\u1ea1i A s\u1ebd l\u1edbn h\u01a1n.<\/p>\n

T\u1eeb \u0111\u00f3 suy ra r\u1eb1ng t\u1ec9<\/span> l\u1ec7 c\u1ee7a hai \u00edch l\u1ee3i c\u1eadn bi\u00ean – \u0111\u1ea1i l\u01b0\u1ee3ng quy\u1ebft \u0111\u1ecbnh \u0111\u1ed9 d\u1ed1c c\u1ee7a \u0111\u01b0\u1eddng b\u00e0ng quan (t\u1ee9c t\u1ec9<\/span> l\u1ec7 thay th\u1ebf c\u1eadn bi\u00ean c\u1ee7a n\u00f3) – ph\u1ea3i gi\u1ea3m v\u00e0 t\u1ea1i B, \u0111\u01b0\u1eddng b\u00e0ng quan \u00edt d\u1ed1c h\u01a1n so v\u1edbi \u0111i\u1ec3m A. Do \u0111\u00f3, ch\u00fang ta c\u00f3 th\u1ec3 k\u1ebft lu\u1eadn r\u1eb1ng h\u00e0m \u00edch l\u1ee3i c\u1ed9ng t\u00ednh h\u00e0m \u00fd \u0111\u01b0\u1eddng b\u00e0ng quan c\u00f3 t\u00ednh l\u1ed3i.<\/p>\n

Ch\u00fang ta c\u00f3 th\u1ec3 m\u00f4 t\u1ea3 m\u1ed9t t\u00ednh ch\u1ea5t kh\u00e1c c\u1ee7a h\u00e0m \u00edch l\u1ee3i c\u1ed9ng t\u00ednh b\u1eb1ng \u0111\u1ed3 th\u1ecb tr\u00ean. H\u00e3y quan s\u00e1t s\u1ef1 di chuy\u1ec3n t\u1eeb A \u0111\u1ebfn C. \u0110i\u1ec3m n\u00e0y n\u1eb1m tr\u00ean \u0111\u01b0\u1eddng ng\u00e2n s\u00e1ch cao h\u01a1n. N\u1ebfu \u00edch l\u1ee3i c\u1eadn bi\u00ean c\u1ee7a X ch\u1ec9 ph\u1ee5 thu\u1ed9c v\u00e0o l\u01b0\u1ee3ng h\u00e0ng h\u00f3a X v\u00e0 gi\u1ea3 \u0111\u1ecbnh n\u00e0y c\u0169ng \u0111\u00fang v\u1edbi Y th\u00ec \u00edch l\u1ee3i c\u1eadn bi\u00ean ta\u1ecb C d\u1ed1c h\u01a1n so v\u1edbi t\u1ea1i A.<\/p>\n

L\u00ed<\/span> do \u1edf \u0111\u00e2y \u0111\u01a1n gi\u1ea3n ch\u1ec9 l\u00e0 ch\u00fang ta c\u00f3 nhi\u1ec1u h\u00e0ng h\u00f3a Y h\u01a1n (\u00edch l\u1ee3i c\u1eadn bi\u00ean gi\u1ea3m) v\u00e0 l\u01b0\u1ee3ng h\u00e0ng h\u00f3a X kh\u00f4ng \u0111\u1ed5i (\u00edch l\u1ee3i c\u1eadn bi\u00ean nh\u01b0 c\u0169).<\/p>\n

Ph\u00e2n t\u00edch t\u01b0\u01a1ng t\u1ef1 \u0111\u01b0a ch\u00fang ta \u0111\u1ebfn v\u1edbi nh\u1eadn \u0111\u1ecbnh r\u1eb1ng \u0111\u01b0\u1eddng b\u00e0ng quan \u0111i qua \u0111i\u1ec3m D (v\u00ed d\u1ee5 I2) ph\u1ea3i \u00edt d\u1ed1c h\u01a1n so v\u1edbi \u0111i\u1ec3m A. T\u1eeb \u0111\u00f3 suy ra r\u1eb1ng \u0111\u01b0\u1eddng b\u00e0ng quan ti\u1ebfp tuy\u1ebfn v\u1edbi \u0111\u01b0\u1eddng ng\u00e2n s\u00e1ch m\u1edbi ph\u1ea3i n\u1eb1m \u1edf 1 \u0111i\u1ec3m gi\u1eefa C v\u00e0 D, ch\u1eb3ng h\u1ea1n E.<\/p>\n

Nh\u01b0ng \u0111i\u1ec1u n\u00e0y l\u1ea1i h\u00e0m \u00fd r\u1eb1ng n\u1ebfu c\u00e1c \u00edch l\u1ee3i \u0111\u1ed9c l\u1eadp v\u1edbi nhau, s\u1ef1 thay \u0111\u1ed5i trong thu nh\u1eadp lu\u00f4n lu\u00f4n l\u00e0m cho ng\u01b0\u1eddi ti\u00eau d\u00f9ng mua c\u1ea3 hai h\u00e0ng h\u00f3a nhi\u1ec1u h\u01a1n. Ngh\u0129a l\u00e0 X v\u00e0 Y ph\u1ea3i l\u00e0 h\u00e0ng h\u00f3a th\u00f4ng th\u01b0\u1eddng. B\u1edfi v\u1eady, m\u1ed9t trong nh\u1eefng t\u00ednh ch\u1ea5t c\u1ee7a h\u00e0m \u00edch l\u1ee3i c\u1ed9ng t\u00ednh l\u00e0 ch\u00fang lu\u00f4n h\u00e0m \u00fd nh\u1eefng h\u00e0ng h\u00f3a \u0111\u01b0\u1ee3c \u0111\u01b0a v\u00e0o h\u00e0m \u00edch l\u1ee3i l\u00e0 h\u00e0ng h\u00f3a th\u00f4ng th\u01b0\u1eddng.<\/p>\n

(T\u00e0i li\u1ec7u tham kh\u1ea3o: T\u1eeb \u0111i\u1ec3n Kinh t\u1ebf h\u1ecdc, NXB \u0110\u1ea1i h\u1ecdc Kinh t\u1ebf Qu\u1ed1c d\u00e2n)<\/em><\/p>\n<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"

\n H\u00e0m \u00edch l\u1ee3i c\u1ed9ng t\u00ednh l\u00e0 m\u1ed9t h\u00e0m \u00edch l\u1ee3i c\u00f3 d\u1ea1ng: U = Ua + Ub + Uc. Trong \u0111\u00f3: U l\u00e0 \u00edch l\u1ee3i; Ua, Ub, Uc l\u1ea7n l\u01b0\u1ee3t l\u00e0 \u00edch l\u1ee3i c\u1ee7a c\u00e1c nh\u00f3m h\u00e0ng h\u00f3a a, b, c v\u00e0 c\u00e1c nh\u00f3m n\u00e0y kh\u00f4ng th\u1ec3 thay th\u1ec3 cho nhau.\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\/23853"}],"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=23853"}],"version-history":[{"count":0,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/posts\/23853\/revisions"}],"wp:attachment":[{"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/media?parent=23853"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/categories?post=23853"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/masterskills.org\/blog\/wp-json\/wp\/v2\/tags?post=23853"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}