嗫?暁雲?
范文一：中国历年恩格尔系数
年 份 城镇居民家庭人均可支配收入 农村居民家庭人均纯收入 城镇居民家庭 农村居民家庭 绝对数 (元) 指数 (1978=100) 绝对数 (元) 指数 (1978=100) 恩格尔系数 (%) 恩格尔系数 (%)
1978 343.4 100.0 133.6 100.0 57.5 67.7 1980 477.6 127.0 191.3 139.0 56.9 61.8 1985 739.1 160.4 397.6 268.9 53.3 57.8 1990 1510.2 198.1 686.3 311.2 54.2 58.8
1991 1700.6 212.4 708.6 317.4 53.8 57.6 1992 2026.6 232.9 784.0 336.2 53.0 57.6 1993 2577.4 255.1 921.6 346.9 50.3 58.1 1994 3496.2 276.8 1221.0 364.3 50.0 58.9 1995 4283.0 290.3 1577.7 383.6 50.1 58.6
1996 4838.9 301.6 1926.1 418.1 48.8 56.3 1997 5160.3 311.9 2090.1 437.3 46.6 55.1 1998 5425.1 329.9 2162.0 456.1 44.7 53.4 1999 5854.0 360.6 2210.3 473.5 42.1 52.6 2000 6280.0 383.7 2253.4 483.4 39.4 49.1
2001 6859.6 416.3 2366.4 503.7 38.2 47.7 2002 7702.8 472.1 2475.6 527.9 37.7 46.2 2003 8472.2 514.6 2622.2 550.6 37.1 45.6 2004 9421.6 554.2 2936.4 588.0 37.7 47.2 2005 10493.0 607.4 3254.9 624.5 36.7 45.5
2006 11759.5 670.7 3587.0 670.7 35.8 43.0 2007 13785.8 752.3 4140.4 734.4 36.3 43.1
年份 城镇居民 农村居民
家庭人均可支配收入 恩格尔系数 (%) 家庭人均纯收入 恩格尔系数 (%) 1957 222.0 58.4 70.9 65.7 1965 220.7 59.2 95.1 68.5 1978 343.4 57.5 133.6 67.7 1985 739.1 53.3 397.6 57.8 1990 1510.2 54.2 686.3 58.8 1995 4283.0 50.1 1577.7 58.6 1999 5854.0 42.1 2210.3 52.6 2000 6280.0 39.4 2253.4 49.1 2005 10493.0 36.7 3254.9 45.5 2007 13785.8 36.3 4140.4 43.1
范文二：历年城镇恩格尔系数
年 1978 1980 1985 1989 1990 1991 1992 1993 1994 1995
1996
系数 57.5 56.9 53.31 54.5 54.2 53.8 53 50.3 50 50.1
48.8
年 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
2007 2008 2009 2010 2011 2012 系数 46.6 44.7 42.1 39.4 38.2 37.7 37.1 37.7 36.7
35.8 36.3 37.9 36.5 35.7 36.3 36.2
恩格尔系数(Engel's Coefficient)是食品支出总额占个人消费支出总额的比重。19世纪德国统计学家恩格尔根据统计资料，对消费结构的变化得出一个规律:一个家庭收入越少，家庭收入中(或总支出中)用来购买食物的支出所占的比例就越大，随着家庭收入的增加，家庭收入中(或总支出中)用来购买食物的支出比例则会下降。推而广之，一个国家越穷，每个国民的平均收入中(或平均支出中)用于购买食物的支出所占比例就越大，随着国家的富裕，这个比例呈下降趋势。
联合国根据恩格尔系数的大小，对世界各国的生活水平有一个划分标准，即一个国家平均家
60%为温饱;40%-50%为小康;30%-40%属于相对富裕;庭恩格尔系数大于60%为贫穷;50%-
20%-30%为富足;20%以下为极其富裕。按此划分标准，20世纪90年代，恩格尔系数在20%以下的只有美国，达到16%;欧洲、日本、加拿大，一般在20-30%之间，是富裕状态。东欧国家，一般在30-40%之间，相对富裕，剩下的发展中国家，基本上分布在小康。
国际上常常用恩格尔系数来衡量一个国家和地区人民生活水平的状况。根据联合国粮农组织提出的标准，恩格尔系数在59%以上为贫困，50-59%为温饱，40-50%为小康，30-40%为富裕，低于30%为最富裕。在中国运用这一标准进行国际和城乡对比时，要考虑到那些不可比因素，如消费品价格比价不同、居民生活习惯的差异、以及由社会经济制度不同所产生的特殊因素。对于这些横截面比较中的不可比问题，在分析和比较时应做相应的剔除。另外，在观察历史情况的变化时要注意，恩格尔系数反映的是一种长期的趋势，而不是逐年下降的绝对倾向。它是在熨平短期的波动中求得长期的趋势。
恩格尔系数是根据恩格尔定律得出的比例数，是表示生活水平高低的一个指标。 其计算公式如下:
恩格尔系数,食物支出金额?总支出金额
除食物支出外，衣着、住房、日用必需品等的支出，也同样在不断增长的家庭收入或总支出中，所占比重上升一段时期后，呈递减趋势。
范文三：恩格尔系数之中国味道
恩格尔系数之中国味道
魏城/撰文
Lextbyweicheng 王安/责任编帮
ca1torbywang6n 1857年,普鲁士
统计学家恩格尔
阐明了一个定律:
随着家庭和个人
收入增加,收人中
用于食品方面的
支出比例将逐渐
减小.这一定律被
称为恩格尔定律,
反映这一定律的
系数被称为恩格
尔系数.
上个世纪九十年代初,我离开 中国,去加拿大留学.抵校第二天, 我在操场上遇到了一位比我早来 一
年的中国学生.
闲聊中,他问我是否习惯吃西 餐,我答日:"还行,就是价钱太 高."
他笑了:"嗨,你别什么价钱
都乘以六啊!"
他指的是当时人民币和加元 的兑换率.
"等你拿到打工的第一笔支 票,就知道这里的饮食不算贵 了"他朝我挤了挤眼.
事实证明,他说的没错.
其实,凡是在西方留学的中国 人大概都有同感:不管你的收入来 源是奖学金还是课外打工,伙食费 其实在你的总花销中所占比例并 不高,高的是房租.这与八十年代 末,九十年代初中国房租低廉,伙 食费却占工薪族收入一半以上的 状况正好相反
也就是在那时,我才知道了 "恩格尔系数"这个经济学术语的 真正含义:原来,衡量穷国和富国 的指标之一,就是看居民饮食开销 占其收入的比例有多大啊1 1857年,普鲁士统计学家恩 格尔阐明了一个定律:随着家庭和 个人收入增加,收入中用于食品方 面的支出比例将逐渐减小.这一定 律被称为恩格尔定律,反映这一定 律的系数被称为恩格尔系数. 国际上常常用恩格尔系数来衡量一个国家和
地区居民生活水平的状况.根据联合国粮农组织提
出的标准,恩格尔系数在59'Yo以上为贫困;50至 59'Yo为温饱:40至50%为小康,3O至40%为富裕,低 于30%为最富裕目前一些发达国家的恩格尔系数 均在2o%左右
但我仍有一些迷惑:对欧美国家中那些买不起 房子的下层工薪族来说,虽然如今饮食开销的比例 已大幅降低,大多数情况下都低于40%,但房租仍占 其收入的一大半,他们也能被视为"生活富足"吗? 当我初到加拿大的时候,在日常生活中,我的 确处处感受到中加两国恩格尔系数的对比.但细究 其原因,也不难理解:加拿大粮食价格低,是因为加 拿大的私人大农场机械化程度非常高,单位成本很 低;加拿大水果价格便宜,是因为加拿大融入国际 贸易体系的程度非常高,从中获益也很大,例如,每 磅只有35加分的香蕉,是从仍属穷国的加勒比海 诸国进口的.但中国有这些前提条件吗? 十多年过去了.如今中国城市居民的恩格尔系 数也下降了,但"橘生淮南则为橘,生于淮北则为 枳"其成因和后果与西方相比,有着很大的不同. 最近,北京市统计局,中国国家统计局北京调 查总队公布了最新的调查数据:北京城市居民去年 人均GDP突破5000美元大关,人均消费支出 13244.2元人民币,恩格尔系数降至31.8%,比 2000年降低4.5个百分点.
中国官方通讯社新华社在报道这则消息时,得 出了这样的结论:"北京市居民的生活水平已经从 改革开放初期的'温饱型',上升到目前的'富裕 型'."
"过去生活困难,能吃饱穿暖就不错了.现在
手头宽裕了,在吃上花不了多少钱,就是琢磨着来 _
j
??|
一一一一
economysquare
点健康投资,旅游什么的."一北京13 报))记者还以家住朝阳区的"朱大妈"的 这番话,试图说明北京市民的生活水平已 接近富裕国家水平
不料,新华社和北京13报》的报道发 表之后,却gf出舆论的一片质疑之声. 中国的许多网站上,甚至官方报章上, 都有人发帖,发文议论道:中国老百姓不敢 花更多的钱去买食品,是因为身上背着住 房,医疗和子女教育这"三座大山",他们 手里有点闲钱,是要攒着以备挖掘"三座 大山"的.
时代商报))的首席评论员万应慧讥 讽地说:…牙缝里抠食'抠出来的系数是 不靠谱的."
会富裕和进步'的'新恩格尔系数(如果 有的话)',应该不仅仅用'购买食物的支 出占总收入的比例'来计算"
上述论者提出的质疑均言之成理,联 合国继续使用恩格尔系数亦非全然荒谬. 但在我看来,恩格尔系数只是衡量某国,某 地生活水平的指标之一,而非唯一指标,而
且它只能估穷,不能量富,也就是说,恩格 尔系数超过59%,肯定属于贫穷,但恩格尔 系数低于40~4,并不一定就能定性为富裕. 举例来说,目前许多非洲国家的恩格 尔系数超过59%,他们肯定不是富裕国家; 格尔系数的解读能够完全成立的话,你就 很难理解为什么中国各大城市仍然存在 "内需不足"的问题.我觉得,至少就中国 普通工薪阶层的生活状况来说,就很难仅 以恩格尔系数低于40~4为由,而将其定义 为已从"温饱型"上升为"富裕型". 有人这样说:中国城市居民恩格尔系 数的下降,一方面反映了城市居民收入的 提高,但另一方面也反映了农民收入的相 对下降,恰好折射出目前已成为中国经济 发展瓶颈的"三农"问题.
广州日报》一篇报道则列出了一组 更具讽刺意味的官方统计数字:去年广州 市城镇居民的恩格尔系数为37.31%,但山 西的恩格尔系数早在2003年就跌到 33.5%;宁夏城镇的思格尔系数也在2004 年降至36.o%.该报记者如此发问:"这意 味着山西,宁夏居民比广州居民更早进入 富裕阶段?"
不少人怀疑中国调查计算恩格尔系数 的准确性,还有的人索性直接质疑恩格尔系 数本身的科学性.不读内容,仅仅扫一下网 上这些评论的标题,你便能够窥出字里行间 的满腹狐疑:《不要再拿恩格尔系数"忽
悠"人了》,《恩格尔系数水土不服拿我们 开逗》,((恩格尔系数太不着调))…… 还有人认为,不应再把近150年前一 位普鲁士人提出的计算方法,作为今天社 会富裕程度的衡量标准.
在中国门户网站新浪网上,一位署名 "段永朝"的网友这样写道——
"'吃饱肚皮'应该说仅仅是一个动
'社 物的基本要求,而作为人类来说,衡量但在中国改革开放之前,许多城镇职工的 月收入都在4O元人民币以上,那时他们每 月的伙食费大概不会超过15元,恩格尔系 数低于4,但没有人会说,那时的中国就 是富裕国家,那时月薪4O元的中国职工就 是富人.
其实,当一国居民的思格尔系数低于 40%时,还要看"吃饱肚皮"之外剩下的余 钱是否仍须满足其它基本需求.只有在社会 福利完善,社会保障充足的情况下,低于40"4 的恩格尔系数才可被视为"富裕"的标志. 客观地说,今天中国的富人,确实渐渐 多了起来;白领"小资"的生活,与西方同 类也可一比;即使是普通的工薪阶层,在满 足基本的吃穿消费之外,手中的余钱,也比 上个世纪八十年代末,九十年代初通货膨 胀导致食品价格奇高的时期要多,更远远 超过改革开放前之窘境,但恰如网上某些 论者所说,如今工薪族手中的余钱,是要攒 着以备挖掘住房,医疗和子女教育这"三
座大山"的
如果新华社和《北京13报))对最新恩 我很F-]意这个看法.谷贵固然损城, 但谷贱必定伤农.然而,市场经济的固有 规律与中国现有农业体制的结合,却决定 了农产品价格难以与城市收入同步提高, 原因有三:一,农产品价格弹性很小,用中 国经济学家林毅夫的话说,农产品只要生 产多一点,那价格就会下降比较多,农产 品只要减产一点点,价格便会涨得非常 多;二,农产品市场属于完全竞争市场,在 中国尤其如此.土地承包制下的汪洋大海 般的中国小农经济,决定了任何一家普通 农户根本不可能操纵农产品价格,他只能 被动地接受农产品价格的升降;三,中国 加入世贸组织后,中国农民面临的不仅仅 是本国其他农户的竞争,更可怕的则是来 自成本低得多,技术含量却商得多的外国 大农场的竞争.国际慈善组织乐施会不久 前的一份报告指出,自2001年中国加入 世贸组织以来,美国向中国出口的棉花数 量在4年内飙升了21倍,挤压了中国棉 农的生产.如果中国粮食市场向国际竞争 完全放开,估计后果也将是大同小异. 30
所以,颇具讽刺性的是:恩格尔系数 下降这一消息,对中国城乡居民可能意味
着完全不同的东西.
那么,如何在不重新推高城市思格尔 系数的前提下提高农民的收入呢? 如果把计划经济的解决办法排除在 外,似乎只有两条出路:一,政府对农产品 进行大幅度补贴;二,走工业化,城市化的 道路,减少农民人数,实现从小农经济到 大农场经济的过渡
中国政府最近推出了雄心勃勃的"社会主义新农村"计划,旨在结合农作物补 贴,减税和内陆地区基础设施投资等手 段,以提高农村地区的收入.
西方媒体在报道这一消息时分析说, 欧洲的共同农业政策是花钱让土地停产, 中国则不同,中国的目标是保持尽可能多 的土地用于农业生产,以确保有足够的粮 食.
但中国国家发改委宏观经济研究院 副院长刘福垣认为,这个目标是错误的. 他在接受记者采访时说:"我们应该让农 民进城,因为这是在农村实现规模经济的 唯一途径."
吴庆也持同样的观点.吴庆是中国国 务院发展研究中心的研究人员,目前在英 国曼彻斯特大学商学院进修,他在接受我 的电话采访时说,新宣布的政府补贴,农 业投资,减税等措施在目前来说非常重 要,但长远来说,解决中国"三农"问题的 根本出路还是大农业.
"我说的大农业,当然不是重回改革 前的集体化道路,而应该更接近发达国家 的大农场:农业人口比例要大幅度下降, 但土地经营规模要大,这样成本才会降下 来,农民收入才会大幅度提高."吴庆说. 吴庆的看法和经济合作与发展组织 早些时候一份报告的结论相吻合.这个总 部设在巴黎的组织,在去年年底发表的首 份中国农业综合研究报告中表示:"大量 劳动者从生产率较低的农业,转移至生产 率较高的制造业,是中国经济增长的基本 要素之一."
但在现有的农业土地制度之下,即使 大量的农民进了城,现代化的大农业就能 顺理成章地出现吗?
有人认为,如果不突破目前的农业土 地承包制,那么,留乡种地的农民便不能合 法扩大农业经营规模,而进城打工的民工 最终也会返乡,西方式的现代化大农场永 远无法出现.所以,为了真正从所有权上保 证合法的土地流转,而且在一旦农地受到 征用时充分保障农民的权益,必须实行农 业土地的私有化.
但吴庆反对农地私有化.他的担心是: "万一卖掉土地进城打工的民工失业怎么 办?万一农村出现严重的土地兼并现象怎 么办?没有证据证明,土地兼并一定会导致 农业经营效率的提高,相反,中国历史上的 土地食利阶层是一个最为腐朽的阶层."
吴庆说,实现现代化的大农业,并非只 有土地私有化一条路可走,"在农地问题 上,还有更为复杂,变通的土地所有权安 排."
吴庆介绍说,这些年来,中国学术界和 决策层一直就农村土地所有权问题进行着 深入,热烈的探讨,他认为,中国最终会走 出一条具有中国特色的农业现代化道路. 李志强是我在英国的一个朋友,如今 他经常往返英中两国做生意.上个世纪八 十年代,他在安徽农学院工作期问,曾从事 中国农业改革的研究,并多次去"联产承 包责任制"的发源地小岗村调查.最近他 从中国回来,与我谈起小岗村的又一桩新 闻:曾经在中国第一个冒险分地的小岗村, 多数农户最近又在自愿的基础上把土地合 了起来,成立了股份制农贸公司. 谈到这个中国农村版本的"合久必 分,分久必合"的故事,李志强说:"这次的 合,与人民公社时期的合,有着本质的不 同:这次的合是在自愿基础上的股份制经 营,是市场经济条件下的合,而且绕开了土 地私有化这个难题,是地道中国特色的解 决办法:表面上农民没有土地的所有权,但 他们对土地的处置,实际上却与土地所有 人没有太大的两样."
但据传媒报道,与28年前小岗村农民 自下而上地发起了分地改革不同,今天的 合地改革虽然是自愿的,但发起方式却似
乎是自上而下的:发起者是从安徽省财政 厅派到小岗村任村委书记的沈浩. 显然,如今小岗村的股份制农贸公司, 与西方式的大农场仍然有着很大的不同, 中国的农业改革能否真正避开所有权问 题?吴庆所说的"具有中国特色的农业现 代化道路"能否成功解决"三农"问题?我 们仍需拭目以待.
也许,只有到了中国恩格尔系数下降 的消息不仅是城里人佳音,也是乡下人佳 音的时候,我们才能获得一个较为明确的 答案o
(作者为英国《金融时报>中文网专栏作家) 31
范文四：中国恩格尔系数降幅加大
周工作计划工作手册管理制度工作规范工作程序工作报告服务中心规范行业经济运行状况内部诊断经济形势分析工作质量检查
中国恩格尔系数降幅加大
国家统计局的资料显示,改革开放以来,由于收入持续快速增长,中国城镇居民家庭的恩格尔系数呈现下降趋势,尤其是近年来,恩格尔系数降幅明显加快,1996至2001年间年均下降2.14个百分点。
与1978年的57.5%相比,2001年中国城镇居民家庭恩格尔系数为37.9%,下降19.6个百分点。在整体下降的趋势下,又大体经历了“高位徘徊———波动下降———较快下降”的变动过程。
据报道,与发达国家人均GDP1000美元左右时的情况相比,中国城镇居民家庭的恩格尔系数与美国和日本相当,略低于法国和英国。
本套资料内容包罗国内外几十家著名咨询公司为数百个国内高成长性企业、行业标杆企业所做的管理咨询项目的全部项目资料，IBM、凯捷、普华永道、毕博、波士顿、海问、科尔尼、罗兰贝格、和君创业、埃森哲、太和、安达信、尚道、德勤、朴智、华彩咨询、亚商、市场整合工程项目合同管理质量考核工作计划顾客满意度研究模型培训项目工作细则调研计划东太项目流通环节品质考核经理考评表定量调查报告分析提纲部门职能说明书企业文化企业管理博思智联君合智联员工试用管理制度
周工作计划工作手册管理制度工作规范工作程序工作报告服务中心规范行业经济运行状况内部诊断经济形势分析工作质量检查 华盈恒信、九略、共图、北大纵横、新华信、正略筠策、仁达方略、博思智联、捷盟、柏明顿、美世、翰威特、零点、远卓、麦肯锡、它将直接帮您拥有最权威、最前沿、最有价值、最全面的管理工具，极大的、迅速的提升您的职业视野、能力与您的职业含金量，您的职位、薪酬必将大幅度的提升～
市场整合工程项目合同管理质量考核工作计划顾客满意度研究模型培训项目工作细则调研计划东太项目流通环节品质考核经理考评表定量调查报告分析提纲部门职能说明书企业文化企业管理博思智联君合智联员工试用管理制度
范文五：恩格尔系数在中国
经典名篇
Keynes, Lucas, and Scientific Progress
*ALAN S. BLINDER
In one of those marvelous coincidences of intellectual history, Robert Lucas was born the year after the publication of Keynes? General Theory. For the first thirty-five years of their mutual lives, the two apparently coexisted in harmony. But their relationship has been tumultuous ever since. Lucas has frequently criticized Keynesian economics as poor science; and it is precisely in that spirit that ? want to
address the debate today.
We all know the old joke about the professor who uses the same exam questions year after year, but changes the answers. That joke encapsulates all too well what has happened to macroeconomics these last fifteen years and seems to reflect poorly on economics as a science. Or does it? On second thought, the best answers to scientific questions do change as new observations are made, as new experiments are run, and as better theories are developed. The issue is whether the answers to important questions in macroeconomics have changed for good scientific reasons of for other reasons.
The joke provides the framework for my talk. I will pose eight exam questions; and for each one I will summarize the answers given by Keynes, by Lucas and his followers, and by modern Keynesians. I pick only questions that are answered differently by Keynesians and Locations and that are central to contemporary macroeconomic debates. The focus is on whether the Keynesian or new classical answers have greater claim to being “scientific.” Each student must answer every question.
?. Are Expectations Rational?
Keynes, though no stranger to probability theory, was nonetheless unequivocal in his denial that expectations are what we now call rational:
… a large proportion of our positive activities depend on spontaneous optimism rather than on a mathematical expectation…Only a little more than an expedition to the South Pole, is it based on an exact calculation of benefits to come. Thus if animal spirits are dimmed and the spontaneous optimism falters, leaving us to depend on nothing but a mathematical expectation, enterprise will fade and die…
[1936,pp.161-62]
That attitude left a big loose end in The General Theory. Business investment is supposedly driven by “the state of long-term expectations,” but expectations are not pinned down by the theory, leaving
substantial room for gyrations in macroeconomic activity driven by autonomous changes in animal spirits. That hardly constitutes a tight scientific theory; but Keynes was probably happy to leave the loose end loose. Modern “sunspot theorists” have tightened up the argument considerably, in ways that Keynes might have found congenial.
Lucas, of course, changes the answer to yes. Was this change motivated by empirical evidence that subjective expectations match the conditional expectations generated by models-or even that actual
* Princeton University, Princeton, NJ 08544. I am grateful for stimulating discussions or correspondence with Ben Brake, Andrew Capelin, Mark Gentler, Stephen Goldfield, David Roomer, Andre Shellfire, Robert So low, and Lawrence Summers. A version of this paper with footnotes and complete references is available on request to the author.
85
经典名篇
expectations are unbiased and efficient? No. Indeed, Edward Prescott has boldly asserted that “surveys
cannot be used to test the rational expectations hypothesis”(1977,p.3). Rather, economists are supposed to
convert to rational expectations(RE)because of the unloveliness of the ad hoc expectation mechanisms that preceded it and because RE is more consistent with their (unverified)worldview that people always
optimize at all margins. As Thomas Sergeant put it: “Research in rational expectations…has a momentum
of its own…that…stems from the logical structure of rational expectations as a modeling strategy” (1982,
p. 382). The momentum, you will note, does not stem from empirics. I leave it to you to decide whether these criteria are more like those that led physicists to dump Newton in favor of Einstein, or those that led artists to abandon Monet to follow Picasso.
Modern Keynesians are split on this question. To some, the theoretical appeal of RE and the general idea that expectations should respond to policy changes are sufficient reason to conclude that “rational
expectations is the right initial hypothesis.” Others harbor doubts. I think the weight of the evidence—both
from directly observed expectations and from indirect statistical tests of rationality(usually in conjunction
with some other hypothesis)—is overwhelmingly against the RE hypothesis. Furthermore, RE is not
without theoretical difficulties. We all know that RE models often have multiple equilibrium. More fundamentally, RE is theoretically coherent only in the context of a single agreed-upon model. In an economy in which different people hold different views of the world, the very notion lacks clarity. For example, if Paul Voucher announces today that on New Year?s Day he will raise M1 by 20 percent, I
imagine Lucas and I will make different revisions in our expectations for, say, real GNP in 1987. Whose expectations are “rational?” Heterogeneous beliefs pose serious theoretical problems for RE, As scientists, then, I think we should be hesitant to embrace RE.
?. Is there Involuntary Unemployment?
Keynes said, nay screamed, yes. Lucas not only says no, but questions whether the phrase has meaning. In his words, “To explain why people allocate time to …unemployment we need to known why
they prefer it to all other activities”(1986, p. 38). Notice the words allocate and prefer. In his view, the
unemployed are engaged in intelligent search or purposeful intertemporal substitution. He scoffs at the Keynesian tradition which, “by dogmatically insisting that unemployment be classified as ?involuntary?…
simply cut itself off from serious thinking about the actual options unemployed people are faced with”
(1986, p. 47).
This is a tough question to adjudicate on scientific grounds since the issue is largely definitional and, as Lewis Carroll pointed out, everyone is entitled to his own definitions. In Lucas?s view, a person laid off
from a job can, presumably, shine shoes in a railroad station or sell apples on a street corner. If he is not doing any of these things, he must be choosing not to do so. Both statements like this and reactions to them tend to be polemical. I guess dogmatism is in the ear of the beholder.
However, a few pertinent facts should leaven the ideological debate. First, when the unemployment rate rises, it is layoffs, not quits, that are rising while consumption falls rather than rises—all of which are
bad news for search theory. Second, real wage movements are close to a random walk—which is bad news
for the intertemporal substitution approach. Third, unemployment is heavily concentrated among the long-term unemployed; in 1985, for example, people who were jobless for 27 weeks or more constituted 54 percent of all unemployment and the expected duration of all unemployment and the expected duration of a complete spell of unemployment was 31 weeks. Can that be intertemporal substitution? Fourth, 86
经典名篇
unemployed workers normally accept their first job offer, and those who are looking for work spend an average of only 4 hours per week on search activity. That hardly suggests a predominant role for search in explaining unemployment.
?. Do Wage Movements Quickly Clear the Labor Market?
Keynes certainly thought not, for such reasons as trade union aggressiveness, custom and inertia, and outright stubbornness. Lucas answers yes—though perhaps only in a broad sense. He has, for example,
cited approvingly the competitive contract equilibrium approach in which workers have 100 percent unemployment insurance and, because of indivisibilities, are chosen randomly to work either, say, 40 hours a week or zero—meaning, of course, that unemployed workers have higher utility than employed ones. In Lucas?s opinion, there is “no reason to believe” that competitive models of labor markets that treat
unemployment like leisure commit “a serious strategic error.”
No reason? I think the preponderance of the evidence says otherwise. Unemployment insurance replaces only about 40 percent of lost earning. Lately, only about one-third of the unemployed collect it, Where is the evidence that the unemployed are happier than the employed? Most economists think Lucas?s
distinguished predecessor at the University of Chicago had it right when he wrote, “Under any conceivable
institutional arrangements, and certainly those that now prevail in the United States, there is only a limited amount of flexibility in prices and wages.” And it is hard, for me at least, to look at what has gone on in this country—not to mention in Europe—since 1974 and see clearing labor markets. That the market clearing
approach caught on in this environment is testimony to Lucas?s keen intellect and profound influence, not
to economists? respect for facts.
More than just casual empiricism supports this view; numerous formal econometric studies reject the market-clearing hypothesis against some sort of disequilibria alternative. Unfortunately, it is usually spot-market clearing that is rejected. Equilibrium contracting models in which the wage plays little or no short-run a locative role are difficult to formulate econometrically, much less to reject. Indeed, it is hard to know what observations could contradict such models; theory just leaves too many open possibilities.
Nonetheless, certain observations are worth making. For one, several authors have pointed to interindustry wage differentials that are persistent across both time and space—differentials which are not
easily squared with market clearing. Theoretically, we know that the wage rate may not be able to clear the labor market in a world of imperfect information—not even in the long run. Of course, that efficiency wage
models can be built does not imply that they describe reality. But it does mean that market-clearing models have no particular claim to the theoretical high ground.
In sum, the scientific basis for modeling labor markets—or goods markets for that matter—as
continuously clearing escapes me.
?. Is the Natural Rate of Unemployment a Strong
Attractor for the Actual Rate of Unemployment?
Keynes thought not. Indeed, in his revolutionary zeal, Keynes spoke loosely (loose talk was a
problem for Keynes)of an “unemployment equilibrium”—which would seem to deny the natural rate any
attractive force at all. Lucas answers in the affirmative.
Modern Keynesians have long had trouble with the master?s notion that the master?s notion that the
87
经典名篇
economy could equilibrate below full employment; they prefer to think of unemployment as a long-lasting disequilibria. In the United States at least, the validity of the natural rate hypothesis has not been at issue for a long time. The argument, instead, is over whether the speed of convergence to the natural rate is rapid or glacial.
On this, the American evidence is unequivocal and the European evidence is overwhelming. The U.S. civilian unemployment rate peaked at 8.9 percent in May 1975 and then took almost three years to get back down to 6 percent. It then peaked again at 10.7 percent in November-December 1982; now, four years later, it has yet to fall below 6.7 percent for even a single month. Some will argue that 7 percent is now the natural rate, without worrying much about how it grew so high. My view is that a theory that allows the natural rate to trundle along after the actual rate is not a natural rate theory at all.
In Europe, the evidence is far more compelling. Unemployment rates rose more or less steadily from 1974 to 1985—from 3 to over 13 percent in Britain, from 2.8 to 10.5 percent in France, and from 1.6 to 8 percent in Germany. Some young men in these countries have never held a job and many never be productive workers. Facts like these have prompted several authors to seek models which explicitly reject the natural rate hypothesis in favor of hysteretic. And recent econometric work suggests hysteretic in postwar U.S. real GNP as well. It may well be that Keynesians caved in too readily to the natural rate hypothesis.
?. Is there a Reliable Short-Run Philips Curve?
Keynes, of course, did not answer this question; the Phillips curve came later. I include it on the exam because Lucas and Sergeant made it central to their attack on Keynesian economics. The alleged failure of the Phillips curve was their main piece of evidence that empirical Keynesian models “were wildly incorrect,
and that the doctrine on which they were based is fundamentally flawed.”(Please notice the adverbs.)
This charge was repeated so often and with such certitude that it became part of the conventional wisdom. Unfortunately, it is, to coin a phrase, wildly incorrect. The fact is that, the Lucas critique notwithstanding, the Phillips curve, wildly incorrect. The fact is that, the Lucas critique notwithstanding, the Phillips curve, once modified to allow for supply shocks(any one of several variables will do), has
been one of the best-behaved empirical regularities in macroeconomics—much better behaved, in fact, than
we had any right to expect. A long list of studies supports this conclusion. Nonetheless, Lucas continues to speak of the Phillips curve as an econometric basket case.
Let me anticipate the obvious objection that saving the Phillips curve after the fact by adding a supply variable does not absolve it of its ex ante forecasting errors. It is true that, while Robert Gordon?s latest
Phillips curves fit the data well, his pre-1972 equations do less well. And they did not predict the rise and fall of OPEC. But there is no sense in which new classical models either anticipated the error or pointed to the solution; like Keynesian models, they were designed to analyze demand shocks. Events in the 1970?s
and 1980?s demonstrated to Keynesian and new Classical economists alike that Marshall?s celebrated
scissors also comes in a giant economy size. It is a debater?s tactic, and a poor one at that, to claim that
supply shocks are outside the purview of Keynesian economics.
?. Does a Change in the Money Supply have Real Effects?
Keynes and the Keynesians answered yes, without bothering to distinguish between anticipated and unanticipated changes. Lucas and the Locations answer that money has real effects only if it is misperceived. In their view, a properly perceived injection of money is like a currency reform. 88
经典名篇
Here, again, the weight of the econometric evidence(though certainly not all of it)suggests that
Keynes had the right answer after all. Robert Barrio?s alleged empirical demonstration that only
unanticipated money has real effects did not hold up. Perceived changes in money are not neutral.
?. Does Social Welfare Rise when Business Cycles are Limited?
Keynes tacitly, but unequivocally, answered yes. If asked for proof, he probably would have chuckled with the condescension of the British upper crust—which is hardly a scientific attitude.
Lucas is carefully agnostic, but clearly leans toward the answer no. He has long been sympathetic to the idea that successful stabilization policies that smooth business cycles may actually decrease welfare. Prescott is less circumspect. Without bothering to draw any distinction between modeling a conclusion and proving it, he asserts that “costly efforts at stabilization are likely to be counterproductive” because
“economic fluctuations are optimal responses to uncertainty in the rate of technological change.” Clearly,
Hamburger triangles look bigger and Oakum gaps smaller near lakes than near oceans. Is Prescott?s attitude
more scientific than Keynes??
I think it is worth taking a moment to explain why Lucas believes that the potential gains from stabilization policy are so small. The postwar standard deviation of log quarterly consumption around trend is about .013. Lucas asks an infinitely lived consumer living under perfect capital markets how much he would be willing to give up to reduce this small standard deviation to zero. Unsurprisingly, the answer comes back: not much. So Lucas concludes that “that post-war business cycle is just not a very important
problem in terms of individual welfare.” That is a stunning assertion, especially when juxtaposed against
the conventional wisdom that governments rise and fall on the vicissitudes of the business cycle.
Lucas?s conclusion, it seems to me, ignores a few pertinent facts. First, the cycle is not mainly in consumer expenditures, much less in consumption. Indeed, there is virtually no cycle at all in spending on no durables and services. Are large swings in consumer durables, in inventories, and in fixed in vestment all socially costless? Don?t these ups and downs impose serious adjustment costs and dislocations on society?
Second, Lucas?s calculation assumes that cyclical fluctuations take place around an unchanged trend, with booms as likely as recessions. But what if recessions leave permanent scars on either labor or capital or productivity? What if there is hysteric?s, so the natural rate hypothesis fails? What if there is a systematic tendency for output to be too low on average? Then the Keynesian goal of filling in troughs without shaving off peaks starts to make sense.
Third, Lucas ignores a variety of psychological, sociological, and physiological costs which many people feel are important. Against Lucas?s benign view of the cycle compare the opinion of martin Luther
King, who wrote that “In our society, it is murder, psychologically, to deprive a man of a job or an income. You are in substance saying to that man that he has no right to exist.” The truth, I think, lies somewhere
between Lucas and King.
Finally, it is important to remember that cyclical losses are not distributed uniformly, as Lucas assumes; instead, most people lose little while a minority suffers much. Let me illustrate with some simple calculations. Suppose everyone has log utility and consumes $3000 per quarter. Let a severe recession reduce consumption 4 percent. Utility falls 4.1 percent, which is no big deal, especially since every down is matched by a subsequent up. This is Lucas?s world.
Now change utility to the Stone-Geary form: U=log(C-$1500). Here a 4 percent drop in consumption
reduces utility by 8.3 percent. That seems a bigger deal. Finally, let the cycle instead reduce the
89
经典名篇
consumption of 10 percent of the population by 40 percent while the other 90 percent loses nothing.(Note
that ? am allowing very generous unemployment insurance here.) With the Stone-Geary utility function,
mean utility declines 16.1 percent. Now we?re talking real tills.
Lucas will, of course, counter that any such problem is best dealt with by better unemployment insurance, not by stabilization policies that interfere with free-market allocations. The same logic says that fire and theft insurance—where moral hazard problems are certainly less severe—obviate the need for fire
and police departments. Isn?t prevention better than insurance?
However, Lucas?s challenge to the Keynesian presumption that smaller cycles are better cycles needs to be addressed scientifically. And, since we can?t observe cyclical fluctuations in utility, that requires the use of theory. The relevant theory is, I think, just beginning to be developed in the burgeoning literature on monopolistic competition and aggregate demand externalities. It would be foolish to say that a definitive answer is in hand; but some good answers many be on the horizon.
?、Must Macroeconomics be Built Up from Neoclassical First Principles?
Keynes answered no. A practical man living in a complex world, he would not close his eyes to apparent deviations from narrow-minded concepts of optimizing behavior—nor even to gross deviations
from rationality. He believed in modeling behavior as it was. Witness his defense of money illusion in labor supply:
Now ordinary experience tells us…that a situation where labor stipulates…for a money-wage rather
It is sometimes said that it than a real wage, so far from being a mere possibility, is the normal case…
would be illogical for labour to resist a reduction of money-wages but not to resist a reduction of real wages… But, whether logical or illogical, experience shows that this is how labour in fact behaves. [p.9]
Lucas and other new classicists take a different view. They emphasize the importance of building up macroeconomic relationships from sound microfoundations, by which they mean the solutions to dynamic, stochastic games. Lapses from what Lucas called “the only ?engine for the discovery of truth?” are one of the chief grounds on which Keynesianism is branded unscientific.
Now, neither side is hostile either to first principles or to factual accuracy. We all agree that the ideal macro theory would be built up logically from first principles and would explain the data well. But we also agree that such a theory is a long way off. The issue is how religiously we must adhere to frictionless neoclassical optimizing principles until that glorious day arrives. Here the devoutness of American economists distinguishes us from our colleagues in other lands. But which attitude leads to better science? Is it better to start deductively from axioms or inductively from facts? When the time comes to choose between internal consistency and consistency with observations, which side should we take? Must we be restricted to microfoundations that preclude the colossal market failures that created macroeconomics as a subdiscipline?
Here followers of Keynes and followers of Lucas often part company. Like Keynes, modern Keynesians are inclined to begin by “taking things as they are”; rigorous optimizing explanations for what they observe(such as nominal wage contracts)can come later. The important thing is to make sure our
models are congruent with the facts. Lucasians, it seems to me, reverse the sequence. They want to begin with fully articulated, tractable models and worry later about realism and descriptive accuracy.
This is a judgment call; but I judge the Keynesian approach more scientific. First, good science need not always be built up from solid microfoundations. Thermodynamics and chemistry, for example, have done pretty well without much micro theory. Boyle?s Law applies directly to aggregates, much like the 90
经典名篇
marginal propensity to consume. And the microfoundations of medicine are often very poor; yet much of it works. Empirical regularities that are formulated and tested directly at the macro level do have a place in science.
Second, it is far from clear that the particular first principles selected by new classical economisis deserve to come first. Why don?t people know the money supply or the price level within very small margins of error? Who imposed a cash-in-advance constraint? Why should price move to equate supply and demand in markets with asymmetric information? Why, Keynes might ask, are these postulates more acceptable as first principles than nominal wage contracting?
Third, the model of man as a strongly rational maximizer is not the only option open to theorists. There are theories of “bounded rationality” and of “near rationality.” Even within the strict optimizing framework, neoclassical tangencies are not the only, nor even the most likely, alternative. Pervasive lumpy transactions costs lead to “the optimality of usually doing nothing,” meaning that it rarely pays to change your decision variable, even if it is not set at the frictionless “optimal” value. In a word, near rationality is
full rationality. It is continuous optimization that would be irrational.
Direct empirical evidence on individual behavior is difficult—some would say impossible—to come
by. But what little we know from experiments by psychologists like Daniel Kahn man and Amos Tversky and others does not suggest that homo sapiens behaves like homo economic us.(Perhaps that is why they
have different names.)Inconsistent choices are common. People put too much weight on what has
happened to them and to their friends and too little on statistical evidence. Framing of the question matters. The von Neumann-Mergansers axioms are routinely violated. It is remarkable how little impact this evidence has had on modern economics. Is that scientific detachment or religious zealotry?
So I have come to the end of my exam with the conclusions you might have guessed at the outset: that when Lucas changed the answers given by Keynes, he was mostly turning better answers into worse ones; that modern Keynesian economics, though far from flawless, has a better claim to being “scientific” than does new classical economics.
REFERENCES
Friedman, Milton, “The Role of Monetary Policy,” American Economic Review, March 1968, 78, 1-17.
Keynes, J. M., The General Theory of Employment, Interest, and Money, London: Harcourt, Brace and World, 1936.
Lucas, Robert E., Jr., “Models of Business Cycles,” paper prepared for the Yrjo Janssen Lectures, Helsinki, Finland, mimeo., March 1986.
Prescott, Edward, “Should Control Theory be Used for Economic Stabilization?,” in Karl Brunner and Alan Seltzer, eds., Optimal Policies, Control Theory, and Technological Exports, Vol. 7, Carnegie-Rochester Conferences on Public Policy, Journal of Monetary Economics, Supple. 1997, 13-38.
, “Theory Ahead of Business Cycle Measurement,” Federal Reserve Bank of Minneapolis Research Department Staff Report 102, February 1986.
Sergeant, Thomas J., “Beyond Demand and Supply Curves in Macroeconomics,” American Economic Review Proceedings, May 1982, 72, 382-89.
(责任编辑:袁 媛)
91
