微观经济学consumerbehavior(编辑修改稿)

微观经济学consumerbehavior(编辑修改稿)内容摘要：

Basket U = FC C 25 = (10) A 25 = 5(5) B 25 = 10() Chapter 3 46 169。 2020 Pearson Education, Inc. Utility Although we numerically rank baskets and indifference curves, numbers are ONLY for ranking A utility of 4 is not necessarily twice as good as a utility of 2 There are two types of rankings Ordinal ranking Cardinal ranking Chapter 3 47 169。 2020 Pearson Education, Inc. Utility Ordinal Utility Function Places market baskets in the order of most preferred to least preferred, but it does not indicate how much one market basket is preferred to another Cardinal Utility Function Utility function describing the extent to which one market basket is preferred to another Chapter 3 48 169。 2020 Pearson Education, Inc. Utility The actual unit of measurement for utility is not important An ordinal ranking is sufficient to explain how most individual decisions are made Chapter 3 49 169。 2020 Pearson Education, Inc. Budget Constraints Preferences do not explain all of consumer behavior Budget constraints also limit an individual’s ability to consume in light of the prices they must pay for various goods and services Chapter 3 50 169。 2020 Pearson Education, Inc. Budget Constraints The Budget Line Indicates all binations of two modities for which total money spent equals total ine We assume only 2 goods are consumed, so we do not consider savings Chapter 3 51 169。 2020 Pearson Education, Inc. The Budget Line Let F equal the amount of food purchased, and C is the amount of clothing Price of food = PF and price of clothing = PC Then PFF is the amount of money spent on food, and PCC is the amount of money spent on clothing Chapter 3 52 169。 2020 Pearson Education, Inc. ICPFP CF The Budget Line The budget line then can be written: All ine is allocated to food (F) and/or clothing (C) Chapter 3 53 169。 2020 Pearson Education, Inc. The Budget Line Different choices of food and clothing can be calculated that use all ine These choices can be graphed as the budget line Example: Assume ine of $80/week, PF = $1 and PC = $2 Chapter 3 54 169。 2020 Pearson Education, Inc. Budget Constraints Market Basket Food PF = $1 Clothing PC = $2 Ine I = PFF + PCC A 0 40 $80 B 20 30 $80 D 40 20 $80 E 60 10 $80 G 80 0 $80 Chapter 3 55 169。 2020 Pearson Education, Inc. CFPPFC S lo p e 21 The Budget Line 10 20 A B D E G (I/PC) = 40 Food 40 60 80 = (I/PF) 20 10 20 30 0 Clothing Chapter 3 56 169。 2020 Pearson Education, Inc. The Budget Line As consumption moves along a budget line from the intercept, the consumer spends less on one item and more on the other The slope of the line measures the relative cost of food and clothing The slope is the negative of the ratio of the prices of the two goods Chapter 3 57 169。 2020 Pearson Education, Inc. The Budget Line The slope indicates the rate at which the two goods can be substituted without changing the amount of money spent We can rearrange the budget line equation to make this more clear Chapter 3 58 169。 2020 Pearson Education, Inc. The Budget Line YXPPPIYPXPIYPXPIYXYYXYXChapter 3 59 169。 2020 Pearson Education, Inc. Budget Constraints The Budget Line The vertical intercept, I/PC, illustrates the maximum amount of C that can be purchased with ine I The horizontal intercept, I/PF, illustrates the maximum amount of F that can be purchased with ine I Chapter 3 60 169。 2020 Pearson Education, Inc. The Budget Line As we know, ine and prices can change As ines and prices change, there are changes in budget lines We can show the effects of these changes on budget lines and consumer choices Chapter 3 61 169。 2020 Pearson Education, Inc. The Budget Line Changes The Effects of Changes in Ine An increase in ine causes the budget line to shift outward, parallel to the original line (holding prices constant). Can buy more of both goods with more ine Chapter 3 62 169。 2020 Pearson Education, Inc. The Budget Line Changes The Effects of Changes in Ine A decrease in ine causes the budget line to shift inward, parallel to the original line (holding prices constant) Can buy less of both goods with less ine Chapter 3 63 169。 2020 Pearson Education, Inc. The Budget Line Changes An increase in ine shifts the budget line outward Food (units per week) Clothing (units per week) 80 120 160 40 20 40 60 80 0 (I = $160) L2 (I = $80) L1 L3 (I = $40) A decrease in ine shifts the budget line inward Chapter 3 64 169。 2020 Pearson Education, Inc. The Budget Line Changes The Effects of Changes in Prices If the price of one good increases, the budget line shifts inward, pivoting from the other good’s intercept. If the price of food increases and you buy only food (xintercept), then you can’t buy as much food. The xintercept shifts in. If you buy only clothing (yintercept), you can buy the same amount. No change in yintercept. Chapter 3 65 169。 2020 Pearson Education, Inc. The Budget Line Changes The Effects of Changes in Prices If the price of one good decreases, the budget line shifts outward, pivoting from the other good’s intercept. If the price of food decreases and you buy only food (xintercept), then you can buy more food. The xintercept shifts out. If you buy only clothing (yintercept), you can buy the same amount. No change in yintercept. Chapter 3 66 169。 2020 Pearson Education, Inc. The Budget Line Changes (PF = 1) L1 An increase in the price of food to $ changes the slope of the budget line and rotates it inward. L3 (PF = 2) (PF = 1/2) L2 A decrease in the price of food to $.50 chan。