Real Income
& Utility
Money income
Money income is just income measured in terms of money.
Y L §g¨C¤éªº¦¬¤J¬O $100¡A³o $100 «K¬O¥Lªº money income¡C
Real income (¹ê½è©Ò±o)
In general, real income is the goods that a person can consume with
his income.
L §gªº money income ¬O $100¡A¦ý¥Lªº¹ê½è©Ò±o¤S¬O¦h¤Ö©O¡H°²³]¥u¦³¤@ºØ product (X)¡A»ù®æ¬° $20¡A
L §gªº¹ê½è©Ò±o«K¬O 5X ¡CY»ù®æ¤U°¦Ü $10¡A¦Ó¥Lªº money income ¤£ÅÜ¡A«h¥L©Ò¯à±o¨ìªºX (§Y¹ê½è©Ò±o) ¼W¥[¡C
¤ñ¸û¹ê½è©Ò±oªº§xÃø
¤UªíÅã¥Ü¦b»ù®æ§ïÅÜ«á¹ï L §gªº¼v’à¡A§ïÅÜ«á¥L¦³§ó¦hªº X ¡A¦ý Y «o¤Ö¤F¡C¥Lªº¹ê½è©Ò±o¬O¦h¤FÁÙ¬O¤Ö¤F©O¡H(³]money
income = $100; Px = price of X; Py = price of Y)
Prices
|
Consumption Choice
|
Real income
|
Before change:
Px = $20; Py = $10
|
2.5X & 5Y
(=$100)
|
2.5X + 5Y
($100)
|
After change:
Px = $10; Py = $20
|
6X & 2Y
(= $100)
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6X + 2Y
($100)
|
Real income & Indifference Curve Approach
n¤ñ¸û¡A«Kn©w¥X¤ñ¸ûªº«ü¼Ð¡C¦b indifference curve approach ¤¤¡Areal income ªº°ª§C¬O ¥H
utility ¬°«ü¼Ðªº¡C utility ·U°ª¡A¹ê½è©Ò±o·U°ª¡C¥ª¹Ïªº¬õ½u¬°»ù®æ§ïÅÜ«eªº budget line¡AA ÂI«h¬O L §gªº¿ï¾Ü¡C
Click button 1
¸û¡u¥¡vªº¬õ½u¬O»ù®æ§ïÅܫ᪺ budget line¡AB ÂI¬O L §g¦b»ù®æ§ïÅܫ᪺¿ï¾Ü¡C§Ṳ́£¯à»¡ B ÂI¥Nªíªº¹ê»Ú©Ò±o¬O°ª¤FÁÙ¬O§C¤F¡C
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¥H utility ¬° real income ªº«ü¼Ð¡AY U1 ¬O L §gªº indifference curve¡A«h A ÂIªº
utility ¥²¤j©ó B ÂI¡AA ÂIªº real income ¸û°ª¡C
Click button 3
Y U2 ¬O L §gªº indifference curve¡A«h B ÂIªº utility ¥²¤j©ó A ÂI¡A§Y B ÂIªº real
income ¸û°ª¡C
Click button 4
Y U3 ¬O L §gªº indifference curve¡A«h Point A ©M Point B ªº utility ¬Û¦P¡A¬O¬°
real income constant ¡C