【文章內(nèi)容簡(jiǎn)介】 The number of firms and the price廠(chǎng)商數(shù)與價(jià)格的關(guān)系 ?The price the typical firm charges depends on the number of firms in the n， ? The more firms, the more petition, and hence the lower the ，競(jìng)爭(zhēng)越劇烈，價(jià)格越低。 ?In the monopolistic petition model firms are assumed to take each others’ prices as 格。 – If each firm treats P as given, we can rewrite the demand curve (65) in the form:將 (65) 改寫(xiě)為： Q = (S/n + S x b x P) – S x b x P (67) 26 ?Profitmaximizing firms set marginal revenue equal to their marginal cost, MR=MC。 ?This generates a negative relationship between the price and the number of firms in the market which is the PP curve:可推導(dǎo)出廠(chǎng)商的價(jià)格函數(shù)，如下： P = c + 1/(b x n) (610) ? The more firms there are in the industry, the lower the price each firm will ：行業(yè)中廠(chǎng)商越多，則各廠(chǎng)商的定價(jià)越低，得出一條向下傾斜的曲線(xiàn)。 27 ? The equilibrium number of firms均衡廠(chǎng)商數(shù)量 ?The downwardsloping curve PP shows that the more firms, the lower the price each firm will charge. ? The more firms, the more petition each firm 曲線(xiàn)：向下傾斜的 PP曲線(xiàn)表示廠(chǎng)商數(shù)量越多，各廠(chǎng)商定價(jià)越低。 ?The upwardsloping curve CC tells us that the more firms there are, the higher the average cost of each ? If the number of firms increases, each firm will sell less, so firms will not be able to move as far down their average cost 傾斜的 CC曲線(xiàn)表示廠(chǎng)商數(shù)量越多，平均成本越多，各廠(chǎng)商銷(xiāo)量越低。交點(diǎn)處為行業(yè)的均衡廠(chǎng)商數(shù)。 28 ? Limitations of the Monopolistic Competition Model壟斷競(jìng)爭(zhēng)的局限性 ? Two kinds of behavior arise in the general oligopoly setting that are excluded by assumption from the monopolistic petition model:上面的分析沒(méi)有考慮到兩種情形： ?Collusive behavior:共謀行為 ? Can raise the profits of all firms at the expense of consumers各廠(chǎng)商共同勾結(jié)制定一個(gè)較高的價(jià)格，以犧牲消費(fèi)者利益為代價(jià)，增進(jìn)利潤(rùn)。 ? May be managed through explicit agreements or through tacit coordination strategies兩種方式：正式協(xié)議和默許 ?Strategic behavior:策略行業(yè) ? Is adopted by firms to affect the behavior of petitors in a desirable way采取排斥競(jìng)爭(zhēng)對(duì)手的行為。 ? Deters potential rivals from entering an industry阻止?jié)撛诘母?jìng)爭(zhēng)者進(jìn)入該行業(yè)。 29 ? The monopolistic petition model can be used to show how trade leads to: 壟斷競(jìng)爭(zhēng)模型能用來(lái)說(shuō)明貿(mào)易形成 ? A lower average price due to scale economies規(guī)模經(jīng)濟(jì)降低平均成本 ? The availability of a greater variety of goods due to product differentiation產(chǎn)品區(qū)別導(dǎo)致多樣化 ? Imports and exports within each industry (intraindustry trade)同一行業(yè)內(nèi)的進(jìn)出口。（行業(yè)內(nèi)貿(mào)易） 64 Monopolistic Competition and Trade壟斷競(jìng)爭(zhēng)和貿(mào)易 30 ? The Effects of Increased Market Size市場(chǎng)規(guī)模擴(kuò)大的影響 ? The number of firms in a monopolistically petitive industry and the prices they charge are affected by the size of the 行業(yè)中廠(chǎng)商數(shù)量和定價(jià)受市場(chǎng)規(guī)模的影響 ? AC=F/Q+c=n*F/S+c S越大， AC越小。較大市場(chǎng)成本曲線(xiàn)位于較小成本曲線(xiàn)的下方。 31 Figure 64: Effects of a Larger Market(P126) 大市場(chǎng)的影響 Cost C, and Price, P Number of firms, n CC1 n1 P1 1 P=c+1/b*n n2 P2 2 CC2 32 ? Gains from an Integrated Market: A Numerical Example從一體化市場(chǎng)中得益：例證 ? International trade allows creation of an integrated market that is larger than each country’s 大的市場(chǎng)。 ?It thus bees possible to offer consumers a greater variety of products and lower prices.(P127)從而為消費(fèi)者提供更多產(chǎn)品和更低的價(jià)格。 33 ? Example: Suppose that automobiles are produced by a monopolistically petitive industry. ? Q = (S/n + S x b x P) – S x b x P ? C = F + c x Q ?Assume the following: ? b = 1/30,000 ? F = $750,000,000 ? c = $5000 ? There are two countries (Home and Foreign) that have the same costs of automobile production. ? Annual sales of automobiles are 900,000 at Home and million at Foreign. 34 Figure 65: Equilibrium in the Automobile Market(P135) 35 Figure 65: Continued 36 Figure 65: Continued 37 Table 62: Hypothetical Example of Gains from Market Integration(P136) 38 ? Economies of Scale and Comparative Advantage規(guī)模經(jīng)濟(jì)與競(jìng)爭(zhēng)優(yōu)勢(shì) ? Assumptions:假設(shè) ?There are two countries: Home (the capitalabundant country) and （本國(guó)資本充裕） ?There are two industries: manufactures (the capitalintensive industry) and food. 兩個(gè)行業(yè)（制造業(yè)和糧食。制造業(yè)是資本密集型行業(yè)） ?Neither country is able to produce the full range of manufactured products by itself due to economies of 于規(guī)模經(jīng)濟(jì)，沒(méi)有一個(gè)國(guó)家能單獨(dú)生產(chǎn)所有的制造品 39 Figure 66: Trade in a World Without Increasing Returns(P130) 不存在規(guī)模經(jīng)濟(jì)世界的貿(mào)易 Home本國(guó)資本充裕 (capital abundant) Foreign外國(guó)勞動(dòng)力充裕 (labor abundant) Manufactures制造品 Food糧食 40 ? If manufactures is a monopolistically petitive sector, world trade consists of two parts:如果制造業(yè)是壟斷競(jìng)爭(zhēng)行業(yè)，則世界貿(mào)易分為兩個(gè)部分 ?Intraindustry trade行業(yè)內(nèi)貿(mào)易 ? The exchange o