ECONOMIC MODELS(经济模式) 尼科尔森中级微观ppt
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尼科尔森中级微观经济学课件 (13)
A Two-Input Production Function
• To find average productivity, we hold k=10 and solve
APl = q/l = 60,000l - 1000l2
• APl reaches its maximum where
APl/l = 60,000 - 2000l = 0 l = 30
marginal physical product
of
capital MPk
q k
fk
ห้องสมุดไป่ตู้
marginal physical product
of
labor
MPl
q l
fl
3
Diminishing Marginal Productivity
• The marginal physical product of an input depends on how much of that input is used
12
Marginal Rate of Technical
Substitution (RTS)
• The slope of an isoquant shows the rate
at which l can be substituted for k
k per period
- slope = marginal rate of technical substitution (RTS)
• To show that isoquants are convex, we would like to show that d(RTS)/dl < 0
中级微观经济学 课件
Economic Profit versus Accounting Profit
销售收入（美元）90000, 减：售出货物的成本40000,毛利50000, 减：显性成本：广告10000,折旧10000,水电煤气 3000,财务税2000,杂费5000,计30000。 会计利润（考虑隐性成本前的利润）20000,
∂L/∂l = w - λ(∂f/∂l) = 0 ∂L/∂k = v - λ(∂f/∂k) = 0 ∂L/∂λ = q0 - f(k,l) = 0
Lee, Junqing
Department of Economics , Nankai University
Lee, Junqing
Department of Economics , Nankai University
Lee, Junqing
Department of Economics , Nankai University
Definitions of Costs
z
Definitions of Costs
It is important to differentiate between accounting cost and economic cost
z
z
the accountant’s view of cost stresses out-ofpocket expenses, historical costs, depreciation, and other bookkeeping entries economists focus more on opportunity cost
z
Cost-Minimizing Input Choices
we could examine how a firm would choose k and l to maximize profit
中级微观经济学chap017.ppt
McGraw-Hill/Irwin
Copyright © 2001 by The McGraw-Hill Companies, Inc. All rights reserved.
17 - 7
Economists’ Differing Views About Social Policy
All economists agree that any policy proposal must embody both economic analysis and value judgments since the goals of policy reflect value judgments.
Copyright © 2001 by The McGraw-Hill Companies, Inc. All rights reserved.
17 - 4
Economists’ Differing Views About Social Policy
Economists have differing views on social policy because:
Their suggestions for social policy are determined by their subjective value judgments (normative views) as well as by their economic analyses.
McGraw-Hill/Irwin
McGraw-Hill/Irwin
Copyright © 2001 by The McGraw-Hill Companies, Inc. All rights reserved.
中级微观经济学(全套课件233P) ppt课件
➢ 第二套房子将出租给愿付490美元的人，随着我们沿需 求曲线向下移动，依此类推。
价格歧视（差别价格）垄断市场均衡
p p1 =$500 p2 =$490 p3 =$475
pe
123
S
得到住房的人与市场 解决的情形正好一样， 即这些人都是按超过 pe的价格租赁的人。 但人们支付的数量不 同。
QD,QS
--- John Maynard Keynes
精品资料
你怎么称呼老师？
如果老师最后没有总结一节课的重点的难点，你 是否会认为老师的教学方法需要改进？ 你所经历的课堂，是讲座式还是讨论式？ 教师的教鞭
“不怕太阳晒，也不怕那风雨狂，只怕先生骂我 笨，没有学问无颜见爹娘 ……” “太阳当空照，花儿对我笑，小鸟说早早早……”
一般垄断市场均衡
❖ 一般垄断者都要限制可能的
p
产量，从而使他的利润最大
化。
❖ 此时均衡价格Pe*高于竞争市
场的均衡价格pe的价格。
空置房 Pe*
pe
S
QD,QS
1.7.2 价格歧视（差别价东，他拥有所有的住房。或者 我们把许许多多个别的房东看作是—个整体，把他们的 行动看作是—个人的行动。
目的 通过假设简化模型 评估判断
1.1建立模型
经济模型的目的： ➢ 帮助提供关于经济现象的精确的洞察力 ➢ 因而：
不同的现象需要不同的模型。 通过假设简化是必要的。 案例：住房市场 ➢ 目的：住房价格由什么决定和谁将得到住房？ ➢ 通过假设简化模型 所有的住房除了位置不同之外，在其他任何方面都是相 同的 外城区住房的价格是外生变量 。 有大量潜在的住房需求者和供给者，即住房市场是完全 竞争的。
➢ 在出租房子时，房东可以决定依次把房子拍卖给愿出最 高价的人。
价格歧视（差别价格）垄断市场均衡
p p1 =$500 p2 =$490 p3 =$475
pe
123
S
得到住房的人与市场 解决的情形正好一样， 即这些人都是按超过 pe的价格租赁的人。 但人们支付的数量不 同。
QD,QS
--- John Maynard Keynes
精品资料
你怎么称呼老师？
如果老师最后没有总结一节课的重点的难点，你 是否会认为老师的教学方法需要改进？ 你所经历的课堂，是讲座式还是讨论式？ 教师的教鞭
“不怕太阳晒，也不怕那风雨狂，只怕先生骂我 笨，没有学问无颜见爹娘 ……” “太阳当空照，花儿对我笑，小鸟说早早早……”
一般垄断市场均衡
❖ 一般垄断者都要限制可能的
p
产量，从而使他的利润最大
化。
❖ 此时均衡价格Pe*高于竞争市
场的均衡价格pe的价格。
空置房 Pe*
pe
S
QD,QS
1.7.2 价格歧视（差别价东，他拥有所有的住房。或者 我们把许许多多个别的房东看作是—个整体，把他们的 行动看作是—个人的行动。
目的 通过假设简化模型 评估判断
1.1建立模型
经济模型的目的： ➢ 帮助提供关于经济现象的精确的洞察力 ➢ 因而：
不同的现象需要不同的模型。 通过假设简化是必要的。 案例：住房市场 ➢ 目的：住房价格由什么决定和谁将得到住房？ ➢ 通过假设简化模型 所有的住房除了位置不同之外，在其他任何方面都是相 同的 外城区住房的价格是外生变量 。 有大量潜在的住房需求者和供给者，即住房市场是完全 竞争的。
➢ 在出租房子时，房东可以决定依次把房子拍卖给愿出最 高价的人。
ECONOMIC MODELS(经济模式) 尼科尔森中级微观ppt
11
The Economic Theory of Value
• The Founding of Modern Economics
– the publication of Adam Smith’s The Wealth of Nations is considered the beginning of modern economics – distinguishing between “value” and “price” continued (illustrated by the diamond-water paradox)
– the Marshallian model is a partial equilibrium model
• focuses only on one market at a time
– to answer more general questions, we need a model of the entire economy
8
Optimization Assumptions
• Optimization assumptions generate precise, solvable models • Optimization models appear to be perform fairly well in explaining reality
• water has a low marginal value and a low marginal cost of production Low price • diamonds have a high marginal value and a high marginal cost of production High price
尼科尔森微观经济学课件 (4)
• The utility-maximization model predicts many aspects of behavior
• Thus, economists assume that people behave as if they made such calculations
2
Complaints about the Economic Approach
Quantity of x
7
First-Order Conditions for a Maximum
• Utility is maximized where the indifference
curve is tangent to the budget constraint
Quantity of y
– the marginal utility of income
15
Interpreting the Lagrangian Multiplier
• At the margin, the price of a good represents the consumer’s evaluation of the utility of the last unit consumed
• The individual’s objective is to maximize
utility = U(x1,x2,…,xn)
subject to the budget constraint
I = p1x1 + p2x2 +…+ pnxn
• Set up the Lagrangian:
L = U(x1,x2,…,xn) + (I - p1x1 - p2x2 -…- pnxn)
• Thus, economists assume that people behave as if they made such calculations
2
Complaints about the Economic Approach
Quantity of x
7
First-Order Conditions for a Maximum
• Utility is maximized where the indifference
curve is tangent to the budget constraint
Quantity of y
– the marginal utility of income
15
Interpreting the Lagrangian Multiplier
• At the margin, the price of a good represents the consumer’s evaluation of the utility of the last unit consumed
• The individual’s objective is to maximize
utility = U(x1,x2,…,xn)
subject to the budget constraint
I = p1x1 + p2x2 +…+ pnxn
• Set up the Lagrangian:
L = U(x1,x2,…,xn) + (I - p1x1 - p2x2 -…- pnxn)
微观经济理论 尼克尔森 lec1
If the profit function was u-shaped, the first order condition would result in q* being chosen and would be minimized
*
q*
Quantity
9
Second Order Conditions
– consumers seek to maximize utility – firms seek to maximize profit
• This chapter introduces the mathematics common to these problems
2
Maximization of a Function of One Variable
d [f ( x ) g ( x )] 6. f '(x) g'(x) dx
d [f ( x ) g ( x )] 7. f ( x )g ' ( x ) f ' ( x )g ( x ) dx
15
Rules for Finding Derivatives
f (x) d g ( x ) f ' ( x )g ( x ) f ( x )g ' ( x ) 8. 2 dx [g ( x )] provided that g ( x ) 0
y f (x1, x2 ,..., xn )
20
Partial Derivatives
• The partial derivative of y with respect to x1 is denoted by
y f or or fx or f1 x1 x1
尼克尔森《微观经济理论基本原理与扩展》第十版官方英文版教学PPT课件
– Continuation of distinction between value and price
• value meant “value in use” • price meant “value in exchange”
The Economic Theory of Value
• Labor theory of exchange value
Positive-Normative Distinction
• Positive economic theories seek to explain the economic phenomena that are observed
• Normative economic theories focus on what “should” be done
costs) – government regulators seek to maximize
public welfare
Optimization Assumptions
• Optimization assumptions generate precise, solvable models
• Optimization models appear to perform fairly well in explaining reality
Slides created by Linda Ghent
Eastern Illinois University
Chapter 1
Economic Models
Theoretical Models
• Economists use models to describe economic activities
• value meant “value in use” • price meant “value in exchange”
The Economic Theory of Value
• Labor theory of exchange value
Positive-Normative Distinction
• Positive economic theories seek to explain the economic phenomena that are observed
• Normative economic theories focus on what “should” be done
costs) – government regulators seek to maximize
public welfare
Optimization Assumptions
• Optimization assumptions generate precise, solvable models
• Optimization models appear to perform fairly well in explaining reality
Slides created by Linda Ghent
Eastern Illinois University
Chapter 1
Economic Models
Theoretical Models
• Economists use models to describe economic activities
中级微观经济学课件
况
市场均衡及其形成机制
市场均衡定义：市场上的供给和需求相等，价格不再变动的一种状态。
形成机制：在竞争市场中，价格变动会引发供给和需求的调整，最终达到市场均衡。
均衡的稳定性：在短期内，市场均衡是相对稳定的；但在长期中，市场均衡可能会因为 外部因素而发生变化。 市场均衡的意义：市场均衡是经济学的核心概念之一，对于理解市场经济运行规律和制 定经济政策具有重要的意义。
价格歧视和垄断定价
价格歧视定义：对同一商品或服务在不同市场以不同价格销售的行为。 目的：增加利润，最大化企业收益。 类型：一级、二级和三级价格歧视。 垄断定价：在独家垄断市场中，企业通过限制产量和抬高价格来最大化利润。
福利经济学及其主要观点
福利经济学定义：研究如何实现社会福利最大化的经济学分支。
消费者行为及其影响因素
消费者偏好：影响消费者行为的重要因素，决定了消费者的购买决策。 收入水平：收入水平的高低直接影响消费者的购买能力，进而影响其消费行为。 价格变动：价格变动对消费者行为有显著影响，价格上升或下降会影响消费者的需求量。 消费者预期：消费者对未来经济状况的预期会影响其当前的消费行为。
类型：垄断竞争市场、寡头市场、完全垄断市场 特点：产品差异、市场壁垒、市场集中度高、价格接受者
寡头市场的形成和竞争策略
寡头市场的定义：少数几家大企业占据了大部分的市场份额，从而影响市 场的价格和产量。
寡头市场的形成原因：市场进入壁垒、规模经济、产品差异化和政府政策 等因素导致市场结构趋于寡头化。
竞争策略：采用价格战、广告战Байду номын сангаас研发和创新等手段来争夺市场份额，提 高自身竞争力。
合作策略：通过达成协议、建立联盟等方式来共同控制市场价格和产量， 实现共赢。
市场均衡及其形成机制
市场均衡定义：市场上的供给和需求相等，价格不再变动的一种状态。
形成机制：在竞争市场中，价格变动会引发供给和需求的调整，最终达到市场均衡。
均衡的稳定性：在短期内，市场均衡是相对稳定的；但在长期中，市场均衡可能会因为 外部因素而发生变化。 市场均衡的意义：市场均衡是经济学的核心概念之一，对于理解市场经济运行规律和制 定经济政策具有重要的意义。
价格歧视和垄断定价
价格歧视定义：对同一商品或服务在不同市场以不同价格销售的行为。 目的：增加利润，最大化企业收益。 类型：一级、二级和三级价格歧视。 垄断定价：在独家垄断市场中，企业通过限制产量和抬高价格来最大化利润。
福利经济学及其主要观点
福利经济学定义：研究如何实现社会福利最大化的经济学分支。
消费者行为及其影响因素
消费者偏好：影响消费者行为的重要因素，决定了消费者的购买决策。 收入水平：收入水平的高低直接影响消费者的购买能力，进而影响其消费行为。 价格变动：价格变动对消费者行为有显著影响，价格上升或下降会影响消费者的需求量。 消费者预期：消费者对未来经济状况的预期会影响其当前的消费行为。
类型：垄断竞争市场、寡头市场、完全垄断市场 特点：产品差异、市场壁垒、市场集中度高、价格接受者
寡头市场的形成和竞争策略
寡头市场的定义：少数几家大企业占据了大部分的市场份额，从而影响市 场的价格和产量。
寡头市场的形成原因：市场进入壁垒、规模经济、产品差异化和政府政策 等因素导致市场结构趋于寡头化。
竞争策略：采用价格战、广告战Байду номын сангаас研发和创新等手段来争夺市场份额，提 高自身竞争力。
合作策略：通过达成协议、建立联盟等方式来共同控制市场价格和产量， 实现共赢。
中级微观经济学课件教材：课件十八讲380页
1、静态分析：不考虑时间因 素，只考察任一时点上的均衡 状态。 2、动态分析：分析有关总量 在一定时间过程中的变动。
实证分析和规范分析：
1、实证经济学：说明“是什么” 的问题。并不涉及到价值判断的 问题。
2、规范经济学：它要说明的是 “应该是什么”的问题。
经济模型分析
把经济理论用变量的函数关系来表示。
• 4、偏好的连续性：即偏好不应具有“跳跃”
• 5、偏好的局部非饱和性，或称局部非餍足性：即 对于任意的消费都不存在充分的满足。
• 6、偏好的强单调性：即消费者总是偏好更多的商 品，或者在心理上反映为多多益善。
• 7、偏好的严格凸性：即任意两个消费束的线性组 合至少应当与原来的消费束中的不好者一样好。
教材与参考
• 鉴于本课程的教学内容较为广泛和分散， 课时相对少，我们不便于指定一本统一的 教科书，整个教学内容以教学的大纲为依 据，在每一个教学单元指出相关的参考文 献。为了达到教学所要求的程度，同学们 可以根据教学的要求参看一些相关的文献。
基本考核方式
• 本课程的考核方式闭卷考试
主要教学参考书
一般地说，对于消费者的消费行为约束的具体表
现形式有：货币收入水平、商品价格和和其它的 行政、法律等因素
• 相对来说，市场的价格是外生的因素
• 若价格向量为， p ( p1, p2, , pn ), pi 0,i 1, 2, , n.
• 消费向量为 x (x1, x2, , xn ), xi 0,i 1, 2, , n.
A E B
O
第二章需求分析及其扩展
一、需求函数与间接效用函数
1、瓦尔拉斯的需求函数
• （1）基本概念：即是在满足消费预算约束 的条件下，消费者获得的最大的效用水平 时的解。
实证分析和规范分析：
1、实证经济学：说明“是什么” 的问题。并不涉及到价值判断的 问题。
2、规范经济学：它要说明的是 “应该是什么”的问题。
经济模型分析
把经济理论用变量的函数关系来表示。
• 4、偏好的连续性：即偏好不应具有“跳跃”
• 5、偏好的局部非饱和性，或称局部非餍足性：即 对于任意的消费都不存在充分的满足。
• 6、偏好的强单调性：即消费者总是偏好更多的商 品，或者在心理上反映为多多益善。
• 7、偏好的严格凸性：即任意两个消费束的线性组 合至少应当与原来的消费束中的不好者一样好。
教材与参考
• 鉴于本课程的教学内容较为广泛和分散， 课时相对少，我们不便于指定一本统一的 教科书，整个教学内容以教学的大纲为依 据，在每一个教学单元指出相关的参考文 献。为了达到教学所要求的程度，同学们 可以根据教学的要求参看一些相关的文献。
基本考核方式
• 本课程的考核方式闭卷考试
主要教学参考书
一般地说，对于消费者的消费行为约束的具体表
现形式有：货币收入水平、商品价格和和其它的 行政、法律等因素
• 相对来说，市场的价格是外生的因素
• 若价格向量为， p ( p1, p2, , pn ), pi 0,i 1, 2, , n.
• 消费向量为 x (x1, x2, , xn ), xi 0,i 1, 2, , n.
A E B
O
第二章需求分析及其扩展
一、需求函数与间接效用函数
1、瓦尔拉斯的需求函数
• （1）基本概念：即是在满足消费预算约束 的条件下，消费者获得的最大的效用水平 时的解。
第12章中级微观经济学
P
S
S1
PPT文档演模板
P0 P1 O• 1、垄断价格歧视
• 房东依次把房子拍卖给愿出最高价的人。
• 市场的价格和供给量与竞争市场的均衡价格和 均衡供给量一致。
• 2、一般垄断者
• 假定房东提供任何数量的房子成本一样，房东 将选择使收益最大化的价格和供给量。
替换商品2的比率。 • 即： △X2/△X1 = -(P1 /P2 ) • 或者说用预算线可以表示计量消费商品的机会成
本。
PPT文档演模板
第12章中级微观经济学
4、预算线的变动 决定预算线的要因是什 么？ 收入、相对价格
1）仅仅收入变化 收入增加预算线向外
平移，收入减少预算 线向内平移。
• 平新乔，《微观经济学十八讲》，北京大
学出版社，2001年。
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第12章中级微观经济学
第1章 市场
• 经济学的研究是通过对社会各种现象建立模型 来进行的。
• 背景：龙洞的房租比广州市中心的房租要高 • 解决问题：房租是如何决定的？用什么方法决
定谁住在龙洞谁住在市中心？哪种方法更好？
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第12章中级微观经济学
第二章 预算约束
• 经济学认为消费者总是选择他们能够负 担的最佳物品。
• “能够负担”——预算约束 • “最佳”——消费者效用最大化
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第12章中级微观经济学
一、预算约束
• 1、消费者的消费束(X1,X2) 表示消费者选择商品X1时的消费量和选择商品X2 时的消费量。
分配不一样。因此，效率和公平是不同的。
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第12章中级微观经济学
三、长期均衡
中级微观经济学 课件
Marginal Revenue Curve
z
Marginal Revenue and Elasticity
z
When the demand curve shifts, its associated marginal revenue curve shifts as well
z
z
a marginal revenue curve cannot be calculated without referring to a specific demand curve
Department of Economics , Nankai University
Inelasticity
CONTENTS
The Nature of Firms Profit Maximization Marginal Revenue Short-Run Supply by a Price-Taking Firm Profit Functions Profit Maximization and Input Demand
z
if the demand curve slopes downward, eq,p < 0 and MR < p if the demand is elastic, eq,p < -1 and marginal revenue will be positive
z
Elastic
3 2 1
eq,p < -1
z
z
shows the revenue per unit yielded by alternative output choices
The marginal revenue curve shows the extra revenue provided by the last unit sold In the case of a downward-sloping demand curve, the marginal revenue curve will lie below the demand curve
中级微观经济学课件
17
Adam Smith--The Invisible Smith--The Hand
Adam Smith (1723-1790) saw prices (1723as force that directed resources into activities where resources were most valuable. Prices told both consumers and firms the “worth” of goods. worth” Smith’ Smith’s somewhat incomplete explanation for prices: determined by the costs to produce the goods.
11
FIGURE 1-1: Production Possibility Frontier 1-
Amount of food per week (lbs.) 10 9.5 A
Opportunity cost of clothing = ½ pound of food
0
3 4
Amount of clothing per week (articles)
4
B
0
3
Amount of clothing 12 per week—articles of clothing
7
Production Possibility Frontier
At B, society can choose to produce 4 lbs. of food and 12 articles of clothing. Without more resources, points outside production possibilities frontier are unattainable
Adam Smith--The Invisible Smith--The Hand
Adam Smith (1723-1790) saw prices (1723as force that directed resources into activities where resources were most valuable. Prices told both consumers and firms the “worth” of goods. worth” Smith’ Smith’s somewhat incomplete explanation for prices: determined by the costs to produce the goods.
11
FIGURE 1-1: Production Possibility Frontier 1-
Amount of food per week (lbs.) 10 9.5 A
Opportunity cost of clothing = ½ pound of food
0
3 4
Amount of clothing per week (articles)
4
B
0
3
Amount of clothing 12 per week—articles of clothing
7
Production Possibility Frontier
At B, society can choose to produce 4 lbs. of food and 12 articles of clothing. Without more resources, points outside production possibilities frontier are unattainable
尼科尔森中级微观经济学课件 (1)
D
Quantity
Q*
3
Economic Efficiency and Welfare Analysis
Price
S At output Q1, total surplus will be smaller
P*
Q1
Q*
At outputs between Q1 and Q*, demanders would value an additional unit more than it would cost suppliers to produce
APPLIED COMPETITIVE ANALYSIS
1
Economic Efficiency and Welfare Analysis
• The area between the demand and the supply curve represents the sum of consumer and producer surplus
P1
been attained
without the price
control
D’
D
Quantity
Q1
Q2
18
Price Controls and Shortages
Price
SS
This shaded triangle
represents the value
of additional
LS producer surplus that
QD = 10 - P
and supply is given by
QS = P - 2
• Market equilibrium occurs where P* = 6 and Q* = 4
Quantity
Q*
3
Economic Efficiency and Welfare Analysis
Price
S At output Q1, total surplus will be smaller
P*
Q1
Q*
At outputs between Q1 and Q*, demanders would value an additional unit more than it would cost suppliers to produce
APPLIED COMPETITIVE ANALYSIS
1
Economic Efficiency and Welfare Analysis
• The area between the demand and the supply curve represents the sum of consumer and producer surplus
P1
been attained
without the price
control
D’
D
Quantity
Q1
Q2
18
Price Controls and Shortages
Price
SS
This shaded triangle
represents the value
of additional
LS producer surplus that
QD = 10 - P
and supply is given by
QS = P - 2
• Market equilibrium occurs where P* = 6 and Q* = 4
尼科尔森中级微观经济学课件 (13)
RTS > 0 and is diminishing for
A
kA
increasing inputs of labor
B
kB
q = 20
l per period
lA
lB
13
Marginal Rate of Technical Substitution (RTS)
• The marginal rate of technical substitution (RTS) shows the rate at which labor can be substituted for capital while holding output constant along an isoquant
which diminishes as l increases • This implies that q has a maximum value:
120,000l - 3000l2 = 0 40l = l2 l = 40
• Labor input beyond l = 40 reduces output 8
• But changes in the marginal productivity of labor over time also depend on changes in other inputs such as capital
– we need to consider flk which is often > 0
2fkflfkl (fk )3
fl2fkk )
• Because we have assumed fk > 0, the denominator is positive
尼科尔森中级微观经济学课件 (11)
8
Profit Maximization
• Since MR = MC at the profit-maximizing output and P > MR for a monopolist, the monopolist will set a price greater than marginal cost
firm
P MC 1
P
eQ,P
where eQ,P is the elasticity of demand for the entire market
11
The Inverse Elasticity Rule
• Two general conclusions about monopoly pricing can be drawn:
– the industry’s long-run supply curve is infinitely elastic with a price equal to both marginal and average cost
22
Monopoly and Resource Allocation
– a monopoly will choose to operate only in regions where the market demand curve is elastic
• eQ,P < -1
– the firm’s “markup” over marginal cost depends inversely on the elasticity of market demand
– the price-output combination where MR = MC
Profit Maximization
• Since MR = MC at the profit-maximizing output and P > MR for a monopolist, the monopolist will set a price greater than marginal cost
firm
P MC 1
P
eQ,P
where eQ,P is the elasticity of demand for the entire market
11
The Inverse Elasticity Rule
• Two general conclusions about monopoly pricing can be drawn:
– the industry’s long-run supply curve is infinitely elastic with a price equal to both marginal and average cost
22
Monopoly and Resource Allocation
– a monopoly will choose to operate only in regions where the market demand curve is elastic
• eQ,P < -1
– the firm’s “markup” over marginal cost depends inversely on the elasticity of market demand
– the price-output combination where MR = MC
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8
Optimization Assumptions
• Optimization assumptions generate precise, solvable models • Optimization models appear to be perform fairly well in explaining reality
– the exchange values of goods are determined by what it costs to produce them
• these costs of production were primarily affected by labor costs • therefore, the exchange values of goods were determined by the quantities of labor used to produce them
– focus on the effects of only a few forces at a time – other variables are assumed to be unchanged during the period of study
7
Optimization Assumptions
• because water is plentiful, consuming an additional unit has a relatively low value to individuals
14
The Economic Theory of Value
• Marshallian Supply-Demand Synthesis
17
Supply-Demand Equilibrium
• A more general model is
qD = a + bp
qS = c + dp
Equilibrium qD = qS
a + bp = c + dp
ac p* d b
18
Supply-Demand Equilibrium
– the Marshallian model is a partial equilibrium model
• focuses only on one market at a time
– to answer more general questions, we need a model of the entire economy
– is the basic assumption valid? do firms really seek to maximize profits?
– can the model predict the behavior of real-world firms?
5
Features of Economic Models
Quantity per period
16
P*
D
Q*
Supply-Demand Equilibrium
qD = 1000 - 100p qS = -125 + 125p
Equilibrium qD = qS
1000 - 100p = -125 + 125p
225p = 1125
p* = 5 q* = 500
Microeconomic Theory
Basic Principles and Extensions, 9e
By
WALTER NICHOLSON
Slides prepared by
Linda Ghent
Eastern Illinois University
Copyright ©2005 by South-Western, a division of Thomson Learning. All rights reserved.
– producing diamonds requires more labore Economic Theory of Value
• The Marginalist Revolution
– the exchange value of an item is not determined by the total usefulness of the item, but rather the usefulness of the last unit consumed
• water has a low marginal value and a low marginal cost of production Low price • diamonds have a high marginal value and a high marginal cost of production High price
Price
An increase in demand...
S
7 5
…leads to a rise in the equilibrium price and quantity.
D’ D
500 750
Quantity per period
20
The Economic Theory of Value
• General Equilibrium Models
9
Positive-Normative Distinction
• Positive economic theories seek to explain the economic phenomena that is observed • Normative economic theories focus on what “should” be done
– indirect approach
• shows that the model correctly predicts realworld events
4
Verification of Economic Models
• We can use the profit-maximization model to examine these approaches
11
The Economic Theory of Value
• The Founding of Modern Economics
– the publication of Adam Smith’s The Wealth of Nations is considered the beginning of modern economics – distinguishing between “value” and “price” continued (illustrated by the diamond-water paradox)
A shift in demand will lead to a new equilibrium:
Q’D = 1450 - 100P Q’D = 1450 - 100P = QS = -125 + 125P 225P = 1575
P* = 7
Q* = 750
19
Supply-Demand Equilibrium
• need to include the interrelationships between markets and economic agents
21
The Economic Theory of Value
• The production possibilities frontier can be used as a basic building block for general equilibrium models • A production possibilities frontier shows the combinations of two outputs that can be produced with an economy’s resources
– Alfred Marshall showed that supply and demand simultaneously operate to determine price – prices reflect both the marginal evaluation that consumers place on goods and the marginal costs of producing the goods
1
Chapter 1
ECONOMIC MODELS
2
Theoretical Models
• Economists use models to describe economic activities • While most economic models are abstractions from reality, they provide aid in understanding economic behavior
10
The Economic Theory of Value
• Early Economic Thought
– “value” was considered to be synonymous with “importance” – since prices were determined by humans, it was possible for the price of an item to differ from its value – prices > value were judged to be “unjust”
• Many economic models begin with the assumption that economic actors are rationally pursuing some goal
Optimization Assumptions
• Optimization assumptions generate precise, solvable models • Optimization models appear to be perform fairly well in explaining reality
– the exchange values of goods are determined by what it costs to produce them
• these costs of production were primarily affected by labor costs • therefore, the exchange values of goods were determined by the quantities of labor used to produce them
– focus on the effects of only a few forces at a time – other variables are assumed to be unchanged during the period of study
7
Optimization Assumptions
• because water is plentiful, consuming an additional unit has a relatively low value to individuals
14
The Economic Theory of Value
• Marshallian Supply-Demand Synthesis
17
Supply-Demand Equilibrium
• A more general model is
qD = a + bp
qS = c + dp
Equilibrium qD = qS
a + bp = c + dp
ac p* d b
18
Supply-Demand Equilibrium
– the Marshallian model is a partial equilibrium model
• focuses only on one market at a time
– to answer more general questions, we need a model of the entire economy
– is the basic assumption valid? do firms really seek to maximize profits?
– can the model predict the behavior of real-world firms?
5
Features of Economic Models
Quantity per period
16
P*
D
Q*
Supply-Demand Equilibrium
qD = 1000 - 100p qS = -125 + 125p
Equilibrium qD = qS
1000 - 100p = -125 + 125p
225p = 1125
p* = 5 q* = 500
Microeconomic Theory
Basic Principles and Extensions, 9e
By
WALTER NICHOLSON
Slides prepared by
Linda Ghent
Eastern Illinois University
Copyright ©2005 by South-Western, a division of Thomson Learning. All rights reserved.
– producing diamonds requires more labore Economic Theory of Value
• The Marginalist Revolution
– the exchange value of an item is not determined by the total usefulness of the item, but rather the usefulness of the last unit consumed
• water has a low marginal value and a low marginal cost of production Low price • diamonds have a high marginal value and a high marginal cost of production High price
Price
An increase in demand...
S
7 5
…leads to a rise in the equilibrium price and quantity.
D’ D
500 750
Quantity per period
20
The Economic Theory of Value
• General Equilibrium Models
9
Positive-Normative Distinction
• Positive economic theories seek to explain the economic phenomena that is observed • Normative economic theories focus on what “should” be done
– indirect approach
• shows that the model correctly predicts realworld events
4
Verification of Economic Models
• We can use the profit-maximization model to examine these approaches
11
The Economic Theory of Value
• The Founding of Modern Economics
– the publication of Adam Smith’s The Wealth of Nations is considered the beginning of modern economics – distinguishing between “value” and “price” continued (illustrated by the diamond-water paradox)
A shift in demand will lead to a new equilibrium:
Q’D = 1450 - 100P Q’D = 1450 - 100P = QS = -125 + 125P 225P = 1575
P* = 7
Q* = 750
19
Supply-Demand Equilibrium
• need to include the interrelationships between markets and economic agents
21
The Economic Theory of Value
• The production possibilities frontier can be used as a basic building block for general equilibrium models • A production possibilities frontier shows the combinations of two outputs that can be produced with an economy’s resources
– Alfred Marshall showed that supply and demand simultaneously operate to determine price – prices reflect both the marginal evaluation that consumers place on goods and the marginal costs of producing the goods
1
Chapter 1
ECONOMIC MODELS
2
Theoretical Models
• Economists use models to describe economic activities • While most economic models are abstractions from reality, they provide aid in understanding economic behavior
10
The Economic Theory of Value
• Early Economic Thought
– “value” was considered to be synonymous with “importance” – since prices were determined by humans, it was possible for the price of an item to differ from its value – prices > value were judged to be “unjust”
• Many economic models begin with the assumption that economic actors are rationally pursuing some goal