Independent variable and
dependent
variable
¦b y = f(x) ¤¤¡Ax ¤Î y ¤À§O¬O¦ÛÅÜ¼Æ (independent
variable) ©MÊÅÜ¼Æ (dependent variable)¡C¨ä·N«ä¬O y È·|¦]À³ x ȪºÅܰʦӧïÅÜ¡C
¼Æ¾Çªº¤@¯ë¼gªk·|§â independent variable ©M dependent
variable ¤À§O©ñ¦b x ¶b¤Î y ¶b¡C¥H»Ý¨D¨ç¼Æ (Demand function) ¬°¨Ò¡A¦]¬°»Ý¨D¶q¨ü»ù®æ¼vÅT¡A©Ò¥H»ù®æ
(P) ¬O independent variable¡A¦Ó»Ý¨D¶q (Q) ¬O dependent variable¡C
¦Ò¦Ò±z¡G«ö¼Æ¾Çªº¤@¯ë¼gªk¡A»Ý¨D¦±½u¤¤ªº»ù®æÀ³©ñ¦bx¶b¡AÁÙ¬Oy¶b¡H
x ¶b
y ¶b
Exogenous and endogenous
variable
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¤Î¥~¥ÍÅÜ¼Æ (exogenous variable) ¨âÃþ¡C
¥~¥ÍÅܼƪº¼ÆȬO¤wª¾ (given or autonomous)¡F¦Ó¤º¥ÍÅܼƪº¼ÆÈ«h¥Ñ¼Ò«¬¥»¨pºâ¥X¨Ó¡C
¨Ò¤l¡G¥H x-y ¹Ï¤ÀªR¦b®ü¬v¤½¶é¤@¤Ñªº®ø¶O¤ä¥X¡C
³]¤U¦C¥|ÂI¬O¼vÅT®ø¶O¤ä¥X(E)ªºÅܼơG
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(b) ª±¾÷°Ê¹CÀ¸ªº¦¸¼Æ (g) (§K¶O)
(c) ÁʶR¬ö©À«~ªº¼Æ¶q (s) (³]¨C³æ¦ì $20)
(d) ¤J³õ¶O (³]¨C¦¸ $100)
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¨Ò¤l¡G
Y¤wª¾ÁʶR¬ö©À«~ªº¼Æ¶q¬° 2¡A«h
E= 100 + 20 ¡Ñ 2+ 5q
E=140 + 5q¡C
Y¥~¥ÍÅܼƦp¡uÁʶR¬ö©À«~ªº¼Æ¶q¡vÅܬ° 4¡A«h
E = 100 + 20 ¡Ñ 4 + 5q¡C
E = 180 + 5q
¦Ò¦Ò±z¡G¥H
x-y ¹Ïªí¹F¡uª±¾÷°Ê¹CÀ¸ªº¦¸¼Æ¡v¹ï¡u®ø¶O¤ä¥X¡vªº¼vÅT¡C
¤W¹Ï¾î½uªí¥Ü¡G¡uª±¾÷°Ê¹CÀ¸ªº¦¸¼Æ¡v¹ï¡u®ø¶O¤ä¥X¡vµL¼vÅT¡AµL½×ª±¦h¤Ö¦¸¡A®ø¶O¤ä¥X³£¬O $100¡C