平狄克《微观经济学》(第8版)笔记和课后习题详解

平狄克第八版课后答案【篇一：平狄克微观经济学课后习题答案-第7-8 章】> 1. 显性成本2. 她自己做其他事时会得到的最高收入3. 多用资本,少用工人4. 完全竞争价格给定, 即斜率不变5. 不意味6. 意味着递增7. avcac mc 递增mc=avc 最低点mc=ac 最低点1.1 形9 . 长期扩展线为把等产量线簇上斜率相同点连起来,此时它改变了斜率10 .规模经济基础是内在经济,针对一种产品范围经济基础是同时生产高度相关的产品.练习题1.avc=1000 ac=1000+1000/q非常大,最后为10002. 不对,除非工人只可以在这里找到工作3. 见书后4. 见书后5. 见书后6. 每个均衡点斜率更小7. 不同意,应按不同时段定价,如不可,则同意8. 见书后9.tc=120000+3000(q/40)+2000ac=75+122000/qmc=75ac 随q 减小2 个劳动组,1600 元1/4, 更大的生产能力11.190 万元53 元53 元19 元第七章附录练习题1 、我们考查规模报酬时可由f( ak，al)与af( k，l)之间的关系判断当f( ak，al) af( k，l),表明是规模报酬递增；当f( ak，al) =af( k，l),表明是规模报酬不变；当f( ak，al) af( k，l),表明是规模报酬递减；( a)规模报酬递增；( b)规模报酬不变；( c)规模报酬递增。

2 、根据已知条件，资本价格r=30 ，设劳动价格为w，则成本函数c=30k+ wl联立(1) ，(2)，(3)可得k=(w/3) 1/2 ,l=(300/w) 1/2 ,此时成本最小，代入成本函数c=30k+ wl ，得c=2 ( 300w ) 1/2联立(1) ，(2)，(3)可得k/l=3/4 ,此时成本最小，即生产既定产出的成本最小化的资本和劳动的组合为资本/劳动=3/4。

4、( a)已知q=10k0.8(l-40)0.2 ,得mpl=2(k/ (l-40))0.8 , mpk=8( (l-40) / k)0.2 ,在最小成本点有：mpl/ mpk=w/r即2(k/ (l-40))0.8/8( (l-40) / k)0.2=w/r ，k/( l-40) =4 w/r ，l-40=kr/4w ，0.80.20.2q=10k(l-40)=10 k ( r/4w)，最小需求为:k=q/10(r/4w)0.2 ，l=40+ q (r/4w)0.8/10总成本函数为：tc=10q+kr+lw=10q+q/10((4w)0.2r0.8+(r/4)0.8w0.2)+40w( b)当r=64 ，w=32 时tc=10q+ (2*20.2+0.50.8)32 q/10+1280tc=1280+10q+91.84 q/10=1280+19.184q该技术呈现规模递减。

第1篇导论：市场和价格第1章绪论1.1复习笔记1．微观经济学的主题（1）微观经济学的研究对象微观经济学研究的是个体经济单位（如消费者、工人、投资者、土地所有者和企业）的行为，也研究构成市场与行业的消费者和厂商的相互影响。

微观经济学的核心内容是论证亚当·斯密的“看不见的手”原理。

（2）经济模型经济模型是现代经济理论的一种主要分析方法，也称为经济数学模型，指用数学形式所表述的经济过程或经济理论结构。

现实世界的情况是由各种主要变量和次要变量构成的，因而非常复杂，只有把次要因素排除在外，才能对经济运行进行严格的分析。

运用经济模型，事先做出某些假设，可以排除掉许多次要因素，从而建立起一定的模型，然后通过运用这一模型，可以对错综复杂的现实世界做出简单的描述。

（3）经济理论的局限性在经济学、物理学或者其他学科中，没有一个理论是绝对正确的。

理论的有用性和合理性取决于它是否对其试图解释和预测的一系列现象成功地做出了解释和预测。

比如说，厂商并不总是追求其利润的最大化的，因此，厂商理论只在解释厂商某些行为（如资本投资决策的时机）时才获得了有限的成功。

尽管如此，这一理论确实解释了有关厂商和行业的行为、成长和演变方面的大量现象，所以它已经成为决策者手中一个重要的工具。

2．实证分析和规范分析（1）微观经济学的分析方法微观经济学既研究实证问题，也研究规范问题。

实证问题主要是解释和预测，规范问题则研究“应该如何”。

实证分析和规范分析都是重要的经济学分析方法。

（2）实证分析和规范分析的含义实证分析是进行经济分析的一种重要方法，特点是它对有关命题的逻辑分析，旨在理解经济过程实际是什么、将会是什么、为什么，而不涉及对结果好坏和是否公平的评价，其中不包含任何价值判断。

实证分析既有定性分析，也有定量分析。

规范分析也是经济学分析经济问题的一种方法，它以一定的价值判断作为出发点，提出行为的标准，并研究如何才能符合这些标准。

它力求说明“应该是什么”的问题，或者说，它回答这样的问题：为什么要做出这种选择，而不做出另一种选择？（3）实证分析和规范分析的关系实证分析和规范分析既有联系又有区别。

平狄克《微观经济学》（第8版）教材配套题库生产（圣才出品）第6章生产一、单项选择题1．一种投入的平均产量由下列哪一项中的比率决定？（）A．总产量的变化与总产量之比B．一种投入单位数的变化与所有投入单位数的变化之比C．所有投入的总单位数与一种投入的总单位数之比D．总产量与一种投入的总单位数之比【答案】D【解析】一种投入要素的平均产量＝总产量/该要素的总投入量。

2．边际收益递减规律是指（）。

A．任何一种投入的总产量最终一定会达到最大，且随着该投入单位数的增加而减少B．任何一种投入的平均产量最终一定会达到最小，且随着所有投入的增加而成比例的增加C．任何一种投入的边际产量应该最终都会随着该投入单位数的增加而减少D．任何一种投入的边际产量应该最终都会随着该投入的单位数增加而成比例的减少【答案】C【解析】边际收益递减指在其他投入不变的情况下，随着可变投入的不断增加边际产量最终会下降。

但并不反映边际产量的减少与可变投入的增加在量上是否成比例。

3．如果一种投入的边际产量为正，但它随着投入单位数的增加而递减（）。

A．平均产量正在下降B．总产量达到了最大，正要开始下降C．总产量正在增加，但增加的速度越来越慢D．企业一定是在长期中运作【答案】C【解析】只要边际产量还为正，总产量就一定是在增加的，只是随边际产量递减，总产量的增加速度下降。

边际产量递减，平均产量可能在下降阶段，也可能仍在上升阶段。

4．理性的生产者选择的生产区域应是（）。

A．MP＞AP阶段B．MP下降阶段C．AP下降阶段D．MP与AP相交之点起至MP与横轴交点止【答案】D【解析】生产的第Ⅱ阶段为合理的生产阶段，这一阶段AP＞MP ＞0。

5．假定图中有一条总产量曲线。

若由于技术进步使得劳动更具效率，那么新的总产量曲线（）。

A．应该在第一条总产量曲线之下，且更平坦B．应该在第一条总产量曲线之上，且更平坦C．应该在第一条总产量曲线之下，且更陡峭D．应该在第一条总产量曲线之上，且更陡峭【答案】D【解析】技术进步使得等量劳动能够生产出更大的总产量，且劳动的边际产量更高，而劳动的边际产量在几何图形中表现为总产量曲线的斜率，因此总产量曲线在原曲线之上，且斜率更大，也就是更陡峭。

平狄克《微观经济学》（第8版）笔记和课后习题详解完整版>精研学习䋞>无偿试用20％资料全国547所院校视频及题库全收集考研全套>视频资料>课后答案>往年真题>职称考试第1篇导论：市场和价格第1章绪论1.1复习笔记1.2课后复习题详解1.3课后练习题详解第2章供给和需求的基本原理2.1复习笔记2.2课后复习题详解2.3课后练习题详解第2篇生产者、消费者与竞争性市场第3章消费者行为3.1复习笔记3.2课后复习题详解3.3课后练习题详解第4章个人需求和市场需求4.1复习笔记4.2课后复习题详解4.3课后练习题详解第4章附录需求理论——一种数学的处理方法第5章不确定性与消费者行为5.1复习笔记5.2课后复习题详解5.3课后练习题详解第6章生产6.1复习笔记6.2课后复习题详解6.3课后练习题详解第7章生产成本7.1复习笔记7.2课后复习题详解7.3课后练习题详解第7章附录生产与成本理论——一种数学的处理方法第8章利润最大化与竞争性供给8.1复习笔记8.3课后练习题详解第9章竞争性市场分析9.1复习笔记9.2课后复习题详解9.3课后练习题详解第3篇市场结构与竞争策略第10章市场势力：垄断和买方垄断10.1复习笔记10.2课后复习题详解10.3课后练习题详解第11章有市场势力的定价11.1复习笔记11.2课后复习题详解11.3课后练习题详解第11章附录纵向联合厂商第12章垄断竞争和寡头垄断12.1复习笔记12.2课后复习题详解12.3课后练习题详解第13章博弈论与竞争策略13.1复习笔记13.2课后复习题详解13.3课后练习题详解第14章投入要素市场14.1复习笔记14.2课后复习题详解14.3课后练习题详解第15章投资、时间与资本市场15.1复习笔记15.2课后复习题详解15.3课后练习题详解第4篇信息、市场失灵与政府的角色第16章一般均衡与经济效率16.1复习笔记16.2课后复习题详解16.3课后练习题详解第17章信息不对称的市场17.1复习笔记17.2课后复习题详解17.3课后练习题详解第18章外部性和公共物品18.1复习笔记18.2课后复习题详解附录指定平狄克《微观经济学》教材为考研参考书目的院校列表。

微观经济学平狄克第八版课后答案【篇一：平狄克《微观经济学》课后答案 (中文版) 1-3章】> 1．市场是通过相互作用决定一种或一系列产品价格的买卖双方的集合，因此可以把市场看作决定价格的场所。

行业是出售相同的或紧密相关的产品的厂商的集合，一个市场可以包括许多行业。

2．评价一个理论有两个步骤：首先，需要检验这个理论假设的合理性；第二，把该理论的预测和事实相比较以此来验证它。

如果一个理论无法被检验的话，它将不会被接受。

因此，它对我们理解现实情况没有任何帮助。

3．实证分析解释“是什么”的问题，而规范分析解释的是“应该是什么”的问题。

对供给的限制将改变市场的均衡。

a中包括两种分析，批评这是一种“失败的政策”——是规范分析，批评其破坏了市场的竞争性——是实证分析。

b向我们说明在燃油的配给制下总社会福利的被损坏——是实证分析。

4．由于两个市场在空间上是分离的，商品在两地间的运输是套利实现的条件。

如果运输成本为零，则可以在oklahoma购买汽油，到new jersey出售，赚取差价；如果这个差价无法弥补运输成本则不存在套利机会。

5．商品和服务的数量与价格由供求关系决定。

鸡蛋的实际价格从1970年至1985年的下降，一方面是由于人们健康意识的提高而导致鸡蛋需求的减少，同时也因为生产成本的降低。

在这两种因素下，鸡蛋的价格下降了。

大学教育的实际价格的升高，是由于越来越多的人倾向于获得大学教育而导致需求提高，同时教育的成本也在升高。

在这两方面因素作用下，大学教育费用提高了。

6．日圆相对美圆来说，价值升高，升值前相比，兑换同样数量的日圆需要付出更多的美圆。

由汇率的变化引起购买力的变化，在日本市场出售的美国汽车，由于美圆贬值日圆升值，持有日圆的消费者将较以前支付较底的价格；而在美国市场出售的日本汽车，由于日圆升值美圆贬值，持有美圆的消费者将面对较以前提高的价格。

4.长期弹性和短期弹性区别在于消费者对价格变化的反映速度以及可获得的替代品。

《微观经济学》学问点总结第一章绪论微观经济学争论个体经济单位的行为，包括消费者、工人、投资者、土地全部者、企业，事实上包括任何参与经济运行的个人和法人。

宏观经济学争论经济总量，诸如国民产出的水平和增长率、利率、失业以及通货膨胀。

微观经济学就是关于有限性的，争论如何配置稀缺资源。

重要概念包括权衡取舍，价格等。

微观经济学既关注实证问题，也关注标准问题。

实证问题主要是解释和推想，而标准问题关注的是“应当如何”引号的问题。

独立的经济单位按功能可分为买者和卖者。

市场是买者和卖者的集合，通过他们实际或潜在的相互作用来打算一种或多种商品的价格。

行业是指出售一样或严密相关产品的厂商的集合。

套利是指在一个地方低价买进，然后在另一个地方高价卖出的行为。

完全竞争市场，即有很多买者和卖者的市场，没有任何买者和卖者能够影响价格。

卡特尔是指集体行动的生产者群体。

市场价格，竞争性市场中通行的价格。

市场范围，市场的边界，既包括地理的边界，又包括就产品范围而言的边界。

名义价格，未经通货膨胀调整确实定价格。

实际价格，一种依据总体价格指标衡量的价格，这是经过通胀调整后的价格。

消费者价格指数，CPI，衡量总体价格水平的指标。

生产者价格指数，PPI，衡量半成品和批发品的总体价格水平的指标。

其次章供给和需求的根本原理供给曲线，描绘生产者情愿出售的商品数量与该商品价格之间关系的曲线。

供给的变动表示供给曲线的移动，供给量的变动表示沿着供给曲线的移动。

需求曲线，消费者情愿购置的商品数量与该商品价格之间的关系。

需求的变动表示需求曲线的移动，需求量的变动表示沿着需求曲线的移动。

替代品，一种商品的价格上升会导致另一种商品的需求量增加的两种商品。

互补品，一种商品的价格上升会导致另一种商品的需求量下降的两种商品。

均衡或市场出清价格，供给和需求相等时的价格。

市场机制，自由市场中价格不断变动直到市场出清的趋势。

过剩，供给大于需求的情形。

短缺，需求量大于供给量的情形。

目　录第1篇　导论：市场和价格第1章　绪　论第2章　供给和需求的基本原理第2篇　生产者、消费者与竞争性市场第3章　消费者行为第4章　个人需求和市场需求第5章　不确定性与消费者行为第6章　生　产第7章　生产成本第8章　利润最大化与竞争性供给第9章　竞争性市场分析第3篇　市场结构与竞争策略第10章　市场势力：垄断和买方垄断第11章　有市场势力的定价第12章　垄断竞争和寡头垄断第13章　博弈论与竞争策略第14章　投入要素市场第15章　投资、时间与资本市场第4篇　信息、市场失灵与政府的角色第16章　一般均衡与经济效率第17章　信息不对称的市场第18章　外部性和公共物品附　录　指定平狄克《微观经济学》教材为考研参考书目的院校列表第1篇　导论：市场和价格第1章　绪　论一、单项选择题1．经济学可以被定义为（ ）。

A ．政府对市场制度的干预B ．企业赚取利润的活动C ．研究稀缺资源如何有效配置的问题D ．个人的生财之道2．经济物品是指（ ）。

A ．有用的东西B ．稀缺的物品C ．要用钱购买的物品D ．有用且稀缺的物品C【答案】经济学是研究人们和社会如何做出选择，来使用可以有其他用途的稀缺的经济资源在现在或是将来生产各种物品，并把物品分配给社会的各个成员或集团以供消费之用的一门社会科学。

【解析】D【答案】现实世界中绝大多数的物品都是不能自由取得的，因为资【解析】3．一个经济体必须作出的基本选择是（ ）。

A ．生产什么B ．生产多少，何时生产C ．为谁生产D ．以上都是4．宏观经济学与微观经济学的关系是（ ）。

A ．相互独立的B ．两者建立在共同的理论基础上C ．两者既有联系又有矛盾D ．毫无联系源是稀缺的，要获得这些有限的物品就必须付出代价，这种物品就被称为“经济物品”。

D【答案】经济学所要解决的问题包括：①生产什么；②如何生产；③为谁生产；④何时生产。

【解析】C【答案】宏观经济学所研究的总量经济特征正是由经济体系中无数微观主体（家庭和厂商）的经济行为所决定的，因而微观经济主体的决策行为就构成了宏观经济分析的基础，宏观经济学需要构建自己的微观基础。

平狄克鲁宾费尔德《微观经济学》重点知识点第一章：微观经济学的研究对象：个别经济单位的决策构成行业和市场的消费者和生产者的相互影响微观经济学的理论框架：假设定义分析框架经验研究结论；同时经验研究又同时作用于假设市场和行业的区别：行业是生产一类相同或相关产品的厂商的集合行业是作为市场的供给方出现的。

基本假设：理性人，产权明确和信息完全。

经济模型：是现代西方经济理论的一种重要分析方法，又称经济数学模型，指用数学形式表达的经济过程或经济理论结构。

经济理论具有局限性实证分析（positive analysis）：规范分析（normative analysis）：微观经济学的核心：价格分析（prize analysis）有三个逐步深入的层次，1，分析单个消费者或生产者的经济行为；2，分析单个市场的价格决定问题；3，分析所有单个市场的价格的同时决定。

市场：买者和买者的集合以及由此构成的引起买卖的可能性。

市场的范围：市场的价格：（计算实际价格和名义价格）（基准年消费物价指数/计算年消费物价指数）*计算年的名义价格第二章：供给曲线：对于其他条件不变的情况下，对于市场上能够得到的价格生产者愿意出售的数量供给的变动是由非价格因素决定的其表现为整条曲线的移动（影响供给的有：相关原材料价格变化，技术变化，政策因素和自然因素）供给量的变动是由生产价格变动引起的，其表现为同一条曲线上点的移动需求曲线：对于其他条件不变的情况下，对于不同的价格水平下消费者愿意购买的数量。

需求的曲线是由非价格因素决定的，其表现为整条曲线的移动（影响需求的有：相关替代品的价格变化，消费者偏好，消费者收入和消费者对产品的价格预期）需求量的变动是由生产价格变动引起的，其表现为同一条曲线上点的移动市场的均衡出清,剩余市场机制总结：1，供给和需求相互作用,决定了市场达到均衡状态的价格水平，2，当市场偏离均衡时，市场会自动调整直到从新回到均衡，3，自由市场是市场机制有效的前提。

第2章供给和需求的基本原理一、单项选择题1．若需求曲线为直角双曲线，则商品价格的上升将引起消费者在该商品上的总花费（）。

A．增加B．下降C．不变D．以上均有可能【答案】C【解析】因为直角双曲线上点弹性处处相等且等于1，即处处为单位弹性。

单位弹性的商品降价或提高价格对厂商的销售收入都没有影响，因此消费者在该商品上的总花费不变。

2．下列说法中正确的是（）。

A．收入弹性取决于商品本身的属性B．不同商品在一定收入范围内具有相同的收入弹性C．同一商品在不同的收入范围内具有相同的收入弹性D．同一商品在不同的收入范围内具有不同的收入弹性【答案】D【解析】收入弹性取决于商品本身的属性和消费者的收入水平。

例如，对同一个消费者而言，任一收入水平下，都会有必需品和奢侈品，其收入弹性自然不同；同时，对同一个消费者而言，收入水平极低时，水果是奢侈品，收入弹性，但收入水平提高后，也许就成了必需品了，收入弹性。

因此，商品不同、收入水平不同，都会有不同的收入弹性。

3．需求价格弹性等于（ ）。

A ．需求曲线上两点间价格的变动量除以需求的变动量B ．需求曲线上需求的变动量除以价格的变动量C ．需求曲线上价格的变动比除以需求的变动比D ．需求曲线上需求的变动比除以价格的变动比【答案】D【解析】需求价格弹性表示商品需求量对自身价格变动的反应程度，即：。

4．商品是正常品，则当其价格下降时（ ）。

A ．商品的需求量会下降B ．商品的需求会下降C ．商品的需求量会上升D ．商品的需求会上升【答案】C【解析】需求变动是指价格之外的变量变化对消费者决策的影响，它与整个需求曲线的移动是对应的；需求量的变动则是价格变化对消费者均衡购买量的影响，它对应于一条需求曲线上点的移动。

因此当商品价格下降时，其需求量会上升。

1I E >1I E <//P Q Q E P P∆=∆x x x x x x5．如果某商品的价格下降5%后，消费者对此商品的货币支出增加了2%，则需求曲线在这一区域内的需求弹性为（ ）。

第6章生产6.1复习笔记1．厂商及其生产决策（1）企业存在的原因企业指由经理人来管理、与企业所有者分离，并雇用和管理大量工人的工厂。

相对于独立工人生产的高成本、低质量和无效性，企业提供了独立工人所欠缺的协调方法，消除了工人进行每项任务所需的协商过程，以及对于任务费用的讨价还价。

因此，企业之所以存在是因为它们可以让商品和服务的生产远比没有企业时高效得多。

（2）生产技术将投入转化为产出（或产品）的过程是厂商运行的中心。

投入也称生产要素，通常可以将投入分为劳动、原材料和资本三大类。

（3）生产函数生产函数描述的是厂商在每一特定的投入要素组合下所能生产的最大产出。

假定有两种投入要素：劳动L和资本K，生产函数可以表示为：q＝F（K，L）这个方程显示了产出与劳动和资本这两种投入要素之间的数量关系。

（4）短期和长期短期指的是在此时段内，至少有一种生产要素是无法变更的。

在此期间，不可变更的投入要素也称为固定投入要素。

长期指的是在此时段内所有的投入要素都是可变的。

在短期内，厂商使用的是固定规模的生产设备，变化的是使用强度；在长期中，企业的规模有了变化，短期中的固定投入要素也是厂商根据以往的生产和销售作出长期决策的结果。

短期与长期之间，并没有一个特定的区分标准，要视具体情况而定。

2．一种可变投入（劳动）下的生产（1）平均产量和边际产量一种要素（如劳动）可变下的生产，可用劳动的平均产量（它度量人的平均生产率）和劳动的边际产量（它度量了生产过程中最后一单位劳动的生产率）来描述。

图6.1一种可变投入下的生产劳动的平均产量AP L是每单位劳动投入的产出，由总产量q除以总劳动投入L得到。

劳动的边际产量MP L是增加一单位劳动所带来的产出增加量。

概括而言，可用以下关系表示：AP L＝产出/劳动投入＝q/LMP L＝产出变化量/劳动变化量＝Δq/ΔL图6.1（a）中的总产量曲线显示了不同劳动投入数量下的产出；（b）图中的边际产量和平均产量曲线由总产量曲线直接推导而得。

第13章博弈论与竞争策略13.1课后复习题详解1．合作博弈和非合作博弈之间的区别是什么？各举出一个例子。

答：博弈按照参与人之间能否达成协议分为合作博弈与非合作博弈。

能达成协议的称为合作博弈，合作博弈强调团队理性；不能达成协议的称为非合作博弈，非合作博弈更注重个人理性。

合作博弈和非合作博弈之间的主要差别是一份有约束力的合同，即双方必须坚持的一项协议，在合作博弈中是可能的，但在非合作博弈中是不可能的。

合作博弈的一个例子是关于一个行业中的两个厂商谈判一项开发一种新技术的联合投资（假设其中任何一个厂商都没有能独自成功的足够知识）。

如果两个厂商能够签订一份分配联合投资利润的有约束力的合同，则使双方都获益的合作的结果就是可能的。

非合作博弈的一个例子就是两竞争的厂商相互考虑到对方的可能的行为，并独立确定价格或广告策略以夺取市场份额的情况。

2．什么是占优策略？为什么一个占优策略均衡是稳定的？答：占优策略指不管其对手采取什么策略，该竞争者采取的策略都是最优策略。

占优策略均衡是指博弈方都采用占优策略所达到的均衡。

占优策略均衡是一种纳什均衡。

纳什均衡指每一个竞争者都确信，在给定竞争对手策略决定的情况下，他选择了最好的策略。

占优策略均衡稳定的原因是参与者在均衡时都没有激励去改变各自的策略。

3．解释纳什均衡的含义。

它与占优策略均衡有何不同？答：（1）纳什均衡的含义纳什均衡指这样一种策略集，在这一策略集中，每一个博弈者都确信，在给定竞争对手策略决定的情况下，他选择了最好的策略。

纳什均衡是由所有参与人的最优策略所组成的一个策略组合，也就是说，给定其他人的策略，任何个人都没有积极性去选择其他策略，从而没有人有积极性去打破这个均衡。

（2）纳什均衡和占优策略均衡的不同占优策略的均衡是纳什均衡的一种特例，不管其他博弈方如何做，占优策略总是最优的。

纳什均衡依赖各博弈方的理性。

占优策略均衡：我所做的是不管你做什么我所能做的最好的；你所做的是不管我做什么你所能做的最好的。

第9章竞争性市场分析9.1 复习笔记1．政府政策的损益评价——消费者剩余和生产者剩余消费者剩余和生产者剩余被用来评价消费者和生产者的损益。

将此方法用于分析天然气价格控制、航空管制、小麦价格支持计划和食糖配额时，可以发现损益可能相当大。

（1）消费者剩余和生产者剩余在无管制的竞争市场上，消费者和生产者按现行市价买卖商品。

但是，对于某些消费者来说，商品价值超过市场价格，他们愿意支付更高的价格。

消费者剩余是消费者获得的超过购买商品支付的总效益或总价值，等于需求曲线与市场价格之间的面积。

生产者剩余测度厂商在提供一定数量的某种产品时实际接受的总支付和愿意接受的最小总支付之间的差额，等于供给曲线与市场价格之间的面积。

总的来看，消费者剩余和生产者剩余测度竞争市场的福利效益。

（2）无谓损失价格控制导致总剩余的净损失，称之为无谓损失。

无谓损失是价格控制造成的低效率，其形成是因为生产者剩余的损失超过了消费者剩余的增加，或者是消费者剩余的损失超过了生产者剩余的增加。

由于政府政策通常将福利从一方转移给另一方，通常导致无谓损失，从而发生净损失。

在部分案例中，无谓损失较小，但有些案例，比如价格支持和进口配额，无谓损失较大。

无谓损失是一种经济低效率的形式，政府在设计和实施政策时必须加以考虑。

2．竞争性市场的效率（1）经济效率经济效率衡量经济主体利用经济资源的有效性。

高的经济效率表示对资源的充分利用或者能以最有效的生产方式进行生产；低的经济效率表示对资源的利用不充分或没有以最有效的方式进行生产。

（2）不同市场组织下的经济效率不同市场组织下的经济效率是不相同的，市场组织的类型直接影响经济效率的高低。

经济学家通过对不同市场条件下厂商的长期均衡状态的分析得出结论：完全竞争市场的经济效率最高，垄断竞争市场较高，寡头市场较低，垄断市场最低。

可见市场的竞争程度越高，则经济效率越高。

（3）政府干预竞争市场政府干预竞争市场并不总是坏事。

政府及政府所代表的社会，可能有经济效率以外的其他社会福利目标。

平狄克鲁宾费尔德《微观经济学》重点知识点第一章：微观经济学的研究对象：个别经济单位的决策构成行业和市场的消费者和生产者的相互影响微观经济学的理论框架：假设定义分析框架经验研究结论；同时经验研究又同时作用于假设市场和行业的区别：行业是生产一类相同或相关产品的厂商的集合行业是作为市场的供给方出现的。

基本假设：理性人，产权明确和信息完全。

经济模型：是现代西方经济理论的一种重要分析方法，又称经济数学模型，指用数学形式表达的经济过程或经济理论结构。

经济理论具有局限性实证分析（positive analysis）：规范分析（normative analysis）：微观经济学的核心：价格分析（prize analysis）有三个逐步深入的层次，1，分析单个消费者或生产者的经济行为；2，分析单个市场的价格决定问题；3，分析所有单个市场的价格的同时决定。

市场：买者和买者的集合以及由此构成的引起买卖的可能性。

市场的范围：市场的价格：（计算实际价格和名义价格）（基准年消费物价指数/计算年消费物价指数）*计算年的名义价格第二章：供给曲线：对于其他条件不变的情况下，对于市场上能够得到的价格生产者愿意出售的数量供给的变动是由非价格因素决定的其表现为整条曲线的移动（影响供给的有：相关原材料价格变化，技术变化，政策因素和自然因素）供给量的变动是由生产价格变动引起的，其表现为同一条曲线上点的移动需求曲线：对于其他条件不变的情况下，对于不同的价格水平下消费者愿意购买的数量。

需求的曲线是由非价格因素决定的，其表现为整条曲线的移动（影响需求的有：相关替代品的价格变化，消费者偏好，消费者收入和消费者对产品的价格预期）需求量的变动是由生产价格变动引起的，其表现为同一条曲线上点的移动市场的均衡出清,剩余市场机制总结：1，供给和需求相互作用,决定了市场达到均衡状态的价格水平，2，当市场偏离均衡时，市场会自动调整直到从新回到均衡，3，自由市场是市场机制有效的前提。

Chapter 9The Analysis of Competitive MarketsReview Questions1. What is meant by deadweight loss? Why does a price ceiling usually result in a deadweight loss?Deadweight loss refers to the benefits lost by consumers and/or producers when markets do not operate efficiently. The term deadweight denotes that these are benefits unavailable to any party. A price ceiling set below the equilibrium price in a perfectly competitive market will result in a deadweight loss because it reduces the quantity supplied by producers. Both producers and consumers lose surplus because less of the good is produced and consumed. The reduced (ceiling) price benefits consumers but hurts producers, so there is a transfer from one group to the other. The real culprit, then, and the primary source of the deadweight loss, is the reduction in the amount of the good in the market.2. Suppose the supply curve for a good is completely inelastic. If the government imposed a priceceiling below the market-clearing level, would a deadweight loss result? Explain.When the supply curve is completely inelastic, it is vertical. In this case there is no deadweight loss because there is no reduction in the amount of the good produced. The imposition of the price ceiling transfers all lost producer surplus to consumers. Consumer surplus increases by the differencebetween the market-clearing price and the price ceiling times the market-clearing quantity.Consumers capture all decreases in total revenue, and no deadweight loss occurs.3. How can a price ceiling make consumers better off? Under what conditions might it make themworse off?If the supply curve is highly inelastic a price ceiling will usually increase consumer surplus because the quantity available will not decline much, but consumers get to purchase the product at a reduced price. If the demand curve is inelastic, on the other hand, price controls may result in a net loss of consumer surplus because consumers who value the good highly are unable to purchase as much as they would like. (See Figure 9.3 on page 321 in the text.) The loss of consumer surplus is greater than the transfer of producer surplus to consumers. So consumers are made better off when demand is relatively elastic and supply is relatively inelastic, and they are made worse off when the opposite is true.4. Suppose the government regulates the price of a good to be no lower than some minimum level.Can such a minimum price make producers as a whole worse off? Explain.With a minimum price set above the market-clearing price, some consumer surplus is transferred to producers because of the higher price, but some producer surplus is lost because consumerspurchase less. If demand is highly elastic, the reduction in purchases can offset the higher priceproducers receive, making producers worse off. In the diagram below, the market-clearing price and quantity are P0 and Q0. The minimum price is set at P', and at this price consumers demand Q'.Assuming that suppliers produce Q' (and not the larger quantity indicated by the supply curve),producer surplus increases by area A due to the higher price, but decreases by the much larger area B because the quantity demanded drops sharply. The result is a reduction in producer surplus. Note thatChapter 9 The Analysis of Competitive Markets141 if suppliers produce more than Q , the loss in producer surplus is even greater because they will have unsold units.5. How are production limits used in practice to raise the prices of the following goods or services:(a) taxi rides, (b) drinks in a restaurant or bar, (c) wheat or corn?Municipal authorities usually regulate the number of taxis through the issuance of licenses ormedallions. When the number of taxis is less than it would be without regulation, those taxis in the market may charge a higher-than-competitive price.State authorities usually regulate the number of liquor licenses. By requiring that any bar or restaurant that serves alcohol have a liquor license and then limiting the number of licenses available, the state limits entry by new bars and restaurants. This limitation allows those establishments that have a license to charge a higher-than-competitive price for alcoholic beverages.Federal authorities usually regulate the number of acres of wheat or corn in production by creating acreage limitation programs that give farmers financial incentives to leave some of their acreage idle.This reduces supply, driving up the price of wheat or corn.6. Suppose the government wants to increase farmers’ incomes. Why do price supports oracreage-limitation programs cost society more than simply giving farmers money?Price supports and acreage limitations cost society more than the dollar cost of these programsbecause the higher price that results in either case will reduce quantity demanded and hence consumer surplus, leading to a deadweight loss because farmers are not able to capture the lost surplus. Giving farmers money does not result in any deadweight loss but is merely a redistribution of surplus from one group to the other.7. Suppose the government wants to limit imports of a certain good. Is it preferable to use animport quota or a tariff? Why?Changes in domestic consumer and producer surpluses are the same under import quotas and tariffs.There will be a loss in (domestic) total surplus in either case. However, with a tariff, the government can collect revenue equal to the tariff times the quantity of imports, and these revenues can beredistributed in the domestic economy to offset some of the domestic deadweight loss. Thus there is less of a loss to the domestic society as a whole with a tariff. With an import quota, foreign producers can capture the difference between the domestic and world price times the quantity of imports.Therefore, with an import quota, there is a loss to the domestic society as a whole. If the national government is trying to minimize domestic welfare loss, it should use a tariff.142Pindyck/Rubinfeld, Microeconomics,Eighth Edition8. The burden of a tax is shared by producers and consumers. Under what conditions willconsumers pay most of the tax? Under what conditions will producers pay most of it? What determines the share of a subsidy that benefits consumers?The burden of a tax and the benefits of a subsidy depend on the elasticities of demand and supply.If the absolute value of the ratio of the elasticity of demand to the elasticity of supply is small, the burden of the tax falls mainly on consumers. If the ratio is large, the burden of the tax falls mainly on producers. Similarly, the benefit of a subsidy accrues mostly to consumers (producers) if the ratio of the elasticity of demand to the elasticity of supply is small (large) in absolute value.9. Why does a tax create a deadweight loss? What determines the size of this loss?A tax creates deadweight loss by artificially increasing price above the free market level, thusreducing the equilibrium quantity. This reduction in quantity reduces consumer as well as producer surplus. The size of the deadweight loss depends on the elasticities of supply and demand and on the size of the tax. The more elastic supply and demand are, the larger will be the deadweight loss. Also, the larger the tax, the greater the deadweight loss.Exercises1. From time to time, Congress has raised the minimum wage. Some people suggested that agovernment subsidy could help employers finance the higher wage. This exercise examines the economics of a minimum wage and wage subsidies. Suppose the supply of low-skilled labor is given by L S= 10w, where L S is the quantity of low-skilled labor (in millions of persons employed each year), and w is the wage rate (in dollars per hour). The demand for labor is given by L D=80 - 10w.a. What will be the free-market wage rate and employment level? Suppose the governmentsets a minimum wage of $5 per hour. How many people would then be employed?In a free-market equilibrium, L S=L D. Solving yields w= $4 and L S=L D= 40. If the minimumwage is $5, then L S= 50 and L D= 30. The number of people employed will be given by the labor demand, so employers will hire only 30 million workers.Chapter 9 The Analysis of Competitive Markets143b. Suppose that instead of a minimum wage, the government pays a subsidy of $1 per hour foreach employee. What will the total level of employment be now? What will the equilibrium wage rate be?Let w s denote the wage received by the sellers (i.e., the employees), and w b the wage paid by the buyers (the firms). The new equilibrium occurs where the vertical difference between the supply and demand curves is $1 (the amount of the subsidy). This point can be found whereL D(w b) =L S(w s), andw s-w b= 1.Write the second equation as w b= w s- 1. This reflects the fact that firms pay $1 less than thewage received by workers because of the subsidy. Substitute for w b in the demand equation:L D(w b) = 80 - 10(w s- 1), soL D(w b) = 90 - 10w s.Note that this is equivalent to an upward shift in demand by the amount of the $1 subsidy. Now set the new demand equal to supply: 90 - 10w s= 10w s. Therefore, w s= $4.50, and L D= 90 -10(4.50) = 45. Employment increases to 45 (compared to 30 with the minimum wage), but wage drops to $4.50 (compared to $5.00 with the minimum wage). The net wage the firm pays falls to $3.50 due to the subsidy.2. Suppose the market for widgets can be described by the following equations:Demand: P= 10 -Q Supply: P=Q- 4where P is the price in dollars per unit and Q is the quantity in thousands of units. Then:a. What is the equilibrium price and quantity?Equate supply and demand and solve for Q: 10 -Q = Q– 4. Therefore Q = 7 thousand widgets.Substitute Q into either the demand or the supply equation to obtain P.P= 10 - 7 = $3.00,orP= 7 - 4 = $3.00.144Pindyck/Rubinfeld, Microeconomics,Eighth Editionb. Suppose the government imposes a tax of $1 per unit to reduce widget consumption andraise government revenues. What will the new equilibrium quantity be? What price will the buyer pay? What amount per unit will the seller receive?With the imposition of a $1.00 tax per unit, the price buyers pay is $1 more than the pricesuppliers receive. Also, at the new equilibrium, the quantity bought must equal the quantitysupplied. We can write these two conditions asP b-P s= 1Q b=Q s.Let Q with no subscript stand for the common value of Q b and Q s. Then substitute the demandand supply equations for the two values of P:(10 -Q) - (Q- 4) = 1Therefore, Q= 6.5 thousand widgets. Plug this value into the demand equation, which is theequation for P b, to find P b= 10 - 6.5 = $3.50. Also substitute Q= 6.5 into the supply equationto get P s=6.5 - 4 = $2.50.The tax raises the price in the market from $3.00 (as found in part a) to $3.50. Sellers, however,receive only $2.50 after the tax is imposed. Therefore the tax is shared equally between buyersand sellers, each paying $0.50.c. Suppose the government has a change of heart about the importance of widgets to thehappiness of the American public. The tax is removed and a subsidy of $1 per unit granted to widget producers. What will the equilibrium quantity be? What price will the buyer pay?What amount per unit (including the subsidy) will the seller receive? What will be the total cost to the government?Now the two conditions that must be satisfied areP s-P b= 1Q b=Q s.As in part b, let Q stand for the common value of quantity. Substitute the supply and demandcurves into the first condition, which yields(Q- 4) - (10 -Q) = 1.Therefore, Q = 7.5 thousand widgets. Using this quantity in the supply and demand equations,suppliers will receive P s= 7.5 - 4 = $3.50, and buyers will pay P b= 10 - 7.5 = $2.50. The totalcost to the government is the subsidy per unit multiplied by the number of units. Thus the cost is ($1)(7.5) = $7.5 thousand, or $7500.3. Japanese rice producers have extremely high production costs, due in part to the highopportunity cost of land and to their inability to take advantage of economies of large-scale production. Analyze two policies intended to maintain Japanese rice production: (1) a per-pound subsidy to farmers for each pound of rice produced, or (2) a per-pound tariff on imported rice.Illustrate with supply-and-demand diagrams the equilibrium price and quantity, domestic rice production, government revenue or deficit, and deadweight loss from each policy. Which policy is the Japanese government likely to prefer? Which policy are Japanese farmers likely to prefer?We have to make some assumptions to answer this question. If you make different assumptions, you may get different answers. Assume that initially the Japanese rice market is open, meaning thatforeign producers and domestic (Japanese) producers both sell rice to Japanese consumers. The worldChapter 9 The Analysis of Competitive Markets145 price of rice is P W. This price is below P0, which is the equilibrium price that would occur in the Japanese market if no imports were allowed. In the diagram below, S is the domestic supply, D is the domestic demand, and Q0 is the equilibrium quantity that would prevail if no imports were allowed. The horizontal line at P W is the world supply of rice, which is assumed to be perfectly elastic. Initially Japanese consumers purchase Q D rice at the world price. Japanese farmers supply Q S at that price, and Q D- Q S is imported from foreign producers.Now suppose the Japanese government pays a subsidy to Japanese farmers equal to the difference between P0 and P W. Then Japanese farmers would sell rice on the open market for P W plus receive the subsidy of P0-P W. Adding these together, the total amount Japanese farmers would receive is P0 per pound of rice. At this price they would supply Q0 pounds of rice. Consumers would still pay P W and buy Q D. Foreign suppliers would import Q D- Q0 pounds of rice. This policy would cost the government (P0-P W)Q0, which is the subsidy per pound times the number of pounds supplied by Japanese farmers. It is represented on the diagram as areas B+E. Producer surplus increases from area C to C+B, so ∆PS=B. Consumer surplus is not affected and remains as area A+B+E+F. Deadweight loss is area E, which is the cost of the subsidy minus the gain in producer surplus.Instead, suppose the government imposes a tariff rather than paying a subsidy. Let the tariff be the same size as the subsidy, P0-P W. Now foreign firms importing rice into Japan will have to sell at the world price plus the tariff: P W+ (P0-P W) =P0. But at this price, Japanese farmers will supply Q0, which is exactly the amount Japanese consumers wish to purchase. Therefore there will be no imports, and the government will not collect any revenue from the tariff. The increase in producer surplus equals area B, as it is in the case of the subsidy. Consumer surplus is area A, which is less than it is under the subsidy because consumers pay more (P0) and consume less (Q0). Consumer surplus decreases by B+E+F. Deadweight loss is E+F: the difference between the decrease in consumer surplus and the increase in producer surplus.Under the assumptions made here, it seems likely that producers would not have a strong preference for either the subsidy or the tariff, because the increase in producer surplus is the same under both policies. The government might prefer the tariff because it does not require any government expenditure. On the other hand, the tariff causes a decrease in consumer surplus, and government officials who are elected by consumers might want to avoid that. Note that if the subsidy and tariff amounts were smaller than assumed above, some tariffs would be collected, but we would still get the same basic results.146Pindyck/Rubinfeld, Microeconomics,Eighth Edition4. In 1983, the Reagan Administration introduced a new agricultural program called thePayment-in-Kind Program. To see how the program worked, let’s consider the wheat market.a. Suppose the demand function is Q D= 28 - 2P and the supply function is Q S= 4 + 4P, whereP is the price of wheat in dollars per bushel, and Q is the quantity in billions of bushels.Find the free-market equilibrium price and quantity.Equating demand and supply, Q D= Q S,28 - 2P= 4 + 4P, or P= $4.00 per bushel.To determine the equilibrium quantity, substitute P= 4 into either the supply equation or thedemand equation:Q S= 4 + 4(4) = 20 billion bushelsandQ D= 28 - 2(4)= 20 billion bushels.b. Now suppose the government wants to lower the supply of wheat by 25% from the free-market equilibrium by paying farmers to withdraw land from production. However, thepayment is made in wheat rather than in dollars—hence the name of the program. Thewheat comes from vast government reserves accumulated from previous price supportprograms. The amount of wheat paid is equal to the amount that could have been harvested on the land withdrawn from production. Farmers are free to sell this wheat on the market.How much is now produced by farmers? How much is indirectly supplied to the market by the government? What is the new market price? How much do farmers gain? Do consumers gain or lose?Because the free-market supply by farmers is 20 billion bushels, the 25% reduction required by the new Payment-In-Kind (PIK) Program means that the farmers now produce 15 billion bushels.To encourage farmers to withdraw their land from cultivation, the government must give them5 billion bushels of wheat, which they sell on the market, so 5 billion bushels are indirectlysupplied by the government.Because the total quantity supplied to the market is still 20 billion bushels, the market price does not change; it remains at $4 per bushel. Farmers gain because they incur no costs for the 5 billion bushels received from the government. We can calculate these cost savings by taking the areaunder the supply curve between 15 and 20 billion bushels. These are the variable costs of producing the last 5 billion bushels that are no longer grown under the PIK Program. To find this area, first determine the prices when Q=15 and when Q = 20. These values are P= $2.75 and P= $4.00.The total cost of producing the last 5 billion bushels is therefore the area of a trapezoid with a base of 20 -15 = 5 billion and an average height of (2.75 + 4.00)/2 = 3.375. The area is 5(3.375) =$16.875 billion, which is the amount farmers gain under the program.The PIK program does not affect consumers in the wheat market because they purchase the same amount at the same price as they did in the free-market case.c. Had the government not given the wheat back to the farmers, it would have stored ordestroyed it. Do taxpayers gain from the program? What potential problems does theprogram create?Taxpayers gain because the government does not incur costs to store or destroy the wheat.Although everyone seems to gain from the PIK program, it can only last while there aregovernment wheat reserves. The program assumes that land removed from production may berestored to production when stockpiles of wheat are exhausted. If this cannot be done, consumersChapter 9 The Analysis of Competitive Markets147 may eventually pay more for wheat-based products. Another potential problem is verifying thatthe land taken out of production is in fact capable of producing the amount of wheat paid tofarmers under the PIK program. Farmers may try to game the system by removing lessproductive land.5. About 100 million pounds of jelly beans are consumed in the United States each year, and theprice has been about 50 cents per pound. However, jelly bean producers feel that their incomes are too low and have convinced the government that price supports are in order. The government will therefore buy up as many jelly beans as necessary to keep the price at $1 per pound.However, government economists are worried about the impact of this program because they have no estimates of the elasticities of jelly bean demand or supply.a. Could this program cost the government more than $50 million per year? Under whatconditions? Could it cost less than $50 million per year? Under what conditions? Illustrate with a diagram.If the quantities demanded and supplied are very responsive to price changes, then a government program that doubles the price of jelly beans could easily cost more than $50 million. In this case, the change in price will cause a large change in quantity supplied, and a large change in quantity demanded. In Figure 9.5.a.i, the cost of the program is ($1)(Q S- Q D). If Q S-Q D is larger than 50 million, then the government will pay more than $50 million. If instead supply and demand arerelatively inelastic, then the increase in price would result in small changes in quantity suppliedand quantity demanded, and (Q S-Q D) would be less than $50 million as illustrated in Figure9.5.a.ii.Figure 9.5.a.iWe can determine the combinations of supply and demand elasticities that yield either result. The elasticity of supply is E S= (%∆Q S)/(%∆P), so the percentage change in quantity supplied is %∆Q S=E S(%∆P). Since the price increase is 100% (from $0.50 to $1.00), %∆Q S= 100E S. Likewise, thepercentage change in quantity demanded is %∆Q D= 100E D. The gap between Q D and Q S inpercentage terms is %∆Q S- %∆Q D= 100E S- 100E D= 100(E S-E D). If this gap is exactly 50% of the current 100 million pounds of jelly beans, the gap will be 50 million pounds, and the cost of the price support program will be exactly $50 million. So the program will cost $50 million if 100(E S-E D) = 50, or148Pindyck/Rubinfeld, Microeconomics,Eighth Edition(E S-E D) = 0.5. If the difference between the elasticities is greater than one half, the program willcost more than $50 million, and if the difference is less than one half, the program will cost less than $50 million. So the supply and demand can each be fairly inelastic (for example, 0.3 and -0.4) and still trigger a cost greater than $50 million.Figure 9.5.a.iib. Could this program cost consumers (in terms of lost consumer surplus) more than $50million per year? Under what conditions? Could it cost consumers less than $50 million per year? Under what conditions? Again, use a diagram to illustrate.When the demand curve is perfectly inelastic, the loss in consumer surplus is $50 million, equal to ($0.50)(100 million pounds). This represents the highest possible loss in consumer surplus, so the loss cannot be more than $50 million per year. If the demand curve has any elasticity at all,the loss in consumer surplus will be less than $50 million. In Figure 9.5.b, the loss in consumersurplus is area A plus area B if the demand curve is the completely inelastic D and only area A if the demand curve is D'.Figure 9.5.bChapter 9 The Analysis of Competitive Markets 1496. In Exercise 4 in Chapter 2 (page 62), we examined a vegetable fiber traded in a competitiveworld market and imported into the United States at a world price of $9 per pound. U.S. domestic supply and demand for various price levels are shown in the following table.PriceU.S. Supply (million pounds) U.S. Demand (million pounds) 32 34 64 28 96 22 128 16 1510 10 18 12 4Answer the following questions about the U.S. market:a. Confirm that the demand curve is given by 402D Q P =-, and that the supply curve is given by 23S Q P =. To find the equation for demand, we need to find a linear function Q D = a + bP so that the line it represents passes through two of the points in the table such as (15, 10) and (12, 16). First, the slope, b , is equal to the “rise” divided by the “run,”10162.1512Q b P ∆-==-=∆- Second, substitute for b and one point, e.g., (15, 10), into the linear function to solve for theconstant, a :102(15),or 40.a a =-=Therefore, Q D = 40 - 2P .Similarly, solve for the supply equation Q S = c + dP passing through two points such as (6, 4) and (3, 2). The slope, d , is422.633Q P ∆-==∆- Solving for c :24(6),or 0.3c c ⎛⎫=+= ⎪⎝⎭Therefore, 2.3S Q P ⎛⎫= ⎪⎝⎭b. Confirm that if there were no restrictions on trade, the United States would import16 million pounds.If there were no trade restrictions, the world price of $9.00 would prevail in the United States. From the table, we see that at $9.00 domestic supply would be 6 million pounds. Similarly,domestic demand would be 22 million pounds. Imports provide the difference between domestic demand and domestic supply, so imports would be 22 - 6 = 16 million pounds.c. If the United States imposes a tariff of $3 per pound, what will be the U.S. price and level ofimports? How much revenue will the government earn from the tariff? How large is thedeadweight loss?With a $3.00 tariff, the U.S. price will be $12 (the world price plus the tariff). At this price,demand is 16 million pounds and U.S. supply is 8 million pounds, so imports are 8 millionpounds (16 - 8). The government will collect $3(8) = $24 million, which is area C in thediagram below. To find deadweight loss, we must determine the changes in consumer andproducer surpluses. Consumers lose area A + B + C + D because they pay the higher price of $12 and purchase fewer pounds of the fiber. U.S. producers gain area A because of the higher priceand the greater quantity they sell. So the deadweight loss is the loss in consumer surplus minus the gain in producer surplus and the tariff revenue. Therefore, DWL = B + D = 0.5(12 - 9)(8 - 6) +0.5(12 - 9)(22 - 16) = $12 million.d. If the United States has no tariff but imposes an import quota of 8 million pounds, what willbe the U.S. domestic price? What is the cost of this quota for U.S. consumers of the fiber?What is the gain for U.S. producers?With an import quota of 8 million pounds, the domestic price will be $12. At $12, the differencebetween domestic demand and domestic supply is 8 million pounds, i.e., 16 million poundsminus 8 million pounds. Note you can also find the equilibrium price by setting demand equal to supply plus the quota so that24028.3P P -=+ The cost of the quota to consumers is equal to area A + B + C + D in the figure above, which isthe reduction in consumer surplus. This equals(12 - 9)(16) + (0.5)(12 - 9)(22 - 16) = $57 million.The gain to domestic producers (increase in producer surplus) is equal to area A , which is(12 - 9)(6) + (0.5)(8 - 6)(12 - 9) = $21 million.7. The United States currently imports all of its coffee. The annual demand for coffee by U.S.consumers is given by the demand curve Q = 250 – 10P , where Q is quantity (in millions ofpounds) and P is the market price per pound of coffee. World producers can harvest and ship coffee to U.S. distributors at a constant marginal (= average) cost of $8 per pound. U.S.distributors can in turn distribute coffee for a constant $2 per pound. The U.S. coffee market is competitive. Congress is considering a tariff on coffee imports of $2 per pound.a. If there is no tariff, how much do consumers pay for a pound of coffee? What is thequantity demanded?If there is no tariff then consumers will pay $10 per pound of coffee, which is found by addingthe $8 that it costs to import the coffee plus the $2 that it costs to distribute the coffee in theUnited States. In a competitive market, price is equal to marginal cost. At a price of $10, thequantity demanded is 150 million pounds.b. If the tariff is imposed, how much will consumers pay for a pound of coffee? What is thequantity demanded?Now add $2 per pound tariff to marginal cost, so price will be $12 per pound, and quantitydemanded is Q = 250 - 10(12) = 130 million pounds.c. Calculate the lost consumer surplus.Lost consumer surplus is (12 - 10)(130) + 0.5(12 - 10)(150 - 130) = $280 million.d. Calculate the tax revenue collected by the government.The tax revenue is equal to the tariff of $2 per pound times the 130 million pounds imported.Tax revenue is therefore $260 million.e. Does the tariff result in a net gain or a net loss to society as a whole?There is a net loss to society because the gain ($260 million) is less than the loss ($280 million).8. A particular metal is traded in a highly competitive world market at a world price of $9 perounce. Unlimited quantities are available for import into the United States at this price. The supply of this metal from domestic U.S. mines and mills can be represented by the equation Q S = 2/3P , where Q S is U.S. output in million ounces and P is the domestic price. The demand for the metal in the United States is Q D = 40 - 2P , where Q D is the domestic demand in million ounces.In recent years the U.S. industry has been protected by a tariff of $9 per ounce. Under pressurefrom other foreign governments, the United States plans to reduce this tariff to zero. Threatened by this change, the U.S. industry is seeking a voluntary restraint agreement that would limit imports into the United States to 8 million ounces per year.a. Under the $9 tariff, what was the U.S. domestic price of the metal?With a $9 tariff, the price of the imported metal in the U.S. market would be $18; the $9 tariffplus the world price of $9. The $18 price, however, is above the domestic equilibrium price. To determine the domestic equilibrium price, equate domestic supply and domestic demand:2402,or $15.3P P P =-=。