【文章內(nèi)容簡(jiǎn)介】 22 Pearson Education, Inc. Publishing as Prentice Hall ? Microeconomics ? Pindyck/Rubinfeld, 7e. THE COMPETITIVE FIRM’S SHORTRUN SUPPLY CURVE The firm’s supply curve is the portion of the marginal cost curve for which marginal cost is greater than average variable cost. The ShortRun Supply Curve for a Competitive Firm Figure In the short run, the firm chooses its output so that marginal cost MC is equal to price as long as the firm covers its average variable cost. The shortrun supply curve is given by the crosshatched portion of the marginal cost curve. Chapter 8: Profit Maximization and Competitive Supply 22 of 36 Copyright 169。 2022 Pearson Education, Inc. Publishing as Prentice Hall ? Microeconomics ? Pindyck/Rubinfeld, 7e. THE COMPETITIVE FIRM’S SHORTRUN SUPPLY CURVE The Response of a Firm to a Change in Input Price Figure When the marginal cost of production for a firm increases (from MC1 to MC2), the level of output that maximizes profit falls (from q1 to q2). The shaded area in the figure gives the total savings to the firm (or equivalently, the reduction in lost profit) associated with the reduction in output from q1 to q2. The ShortRun Profit of a Competitive Firm Chapter 8: Profit Maximization and Competitive Supply 23 of 36 Copyright 169。 2022 Pearson Education, Inc. Publishing as Prentice Hall ? Microeconomics ? Pindyck/Rubinfeld, 7e. THE COMPETITIVE FIRM’S SHORTRUN SUPPLY CURVE Although plenty of crude oil is available, the amount that you refine depends on the capacity of the refinery and the cost of production. The ShortRun Production of Petroleum Products Figure As the refinery shifts from one processing unit to another, the marginal cost of producing petroleum products from crude oil increases sharply at several levels of output. As a result, the output level can be insensitive to some changes in price but very sensitive to others. Chapter 8: Profit Maximization and Competitive Supply 24 of 36 Copyright 169。 2022 Pearson Education, Inc. Publishing as Prentice Hall ? Microeconomics ? Pindyck/Rubinfeld, 7e. 短期供應(yīng)曲線的移動(dòng) ? 當(dāng)投入要素價(jià)格變化時(shí)，同樣產(chǎn)量水平的 MC會(huì)改變，供應(yīng)曲線將發(fā)生移動(dòng) D MC Q P MC =11MPR+22MPR+ ?? +NNMPR Chapter 8: Profit Maximization and Competitive Supply 25 of 36 Copyright 169。 2022 Pearson Education, Inc. Publishing as Prentice Hall ? Microeconomics ? Pindyck/Rubinfeld, 7e. 啟示： 競(jìng)爭(zhēng)性廠商的短期贏利能力 ? 價(jià)格是市場(chǎng)供求總量決定，企業(yè)是價(jià)格的接受者 ? 短期贏利能力決定于生產(chǎn)的企業(yè)的邊際成本和平均成本 ? 進(jìn)一步?jīng)Q定于 生產(chǎn)要素的價(jià)格 和企業(yè)技術(shù)和管理水平?jīng)Q定的 要素的邊際產(chǎn)品 Chapter 8: Profit Maximization and Competitive Supply 26 of 36 Copyright 169。 2022 Pearson Education, Inc. Publishing as Prentice Hall ? Microeconomics ? Pindyck/Rubinfeld, 7e. 定位在全球生產(chǎn)網(wǎng)絡(luò)價(jià)值鏈的低端 ? 處于市場(chǎng)、資金、品牌、技術(shù)全部依靠國(guó)外，而自己只是加工生產(chǎn)的發(fā)展?fàn)顩r –一個(gè)芭比娃娃，在美國(guó)賣價(jià)是 10美元，從中國(guó)出口的價(jià)格大約為 3美元，其中頭發(fā)進(jìn)口于日本，橡膠來自東南亞，布料來自越南，中國(guó)只賺取 費(fèi) . ? 沒有價(jià)格決定能力 Chapter 8: Profit Maximization and Competitive Supply 27 of 36 Copyright 169。 2022 Pearson Education, Inc. Publishing as Prentice Hall ? Microeconomics ? Pindyck/Rubinfeld, 7e. 資源依賴型經(jīng)濟(jì)增長(zhǎng) ? 以單位 GDP產(chǎn)出能耗量表征的能源利用效率，我國(guó)與發(fā)達(dá)國(guó)家差距非常之大。日本為 1，意大利為 ，法國(guó)為 ，德國(guó)為 ，英國(guó)為 ，美國(guó)為 ，加拿大為 ，而 我國(guó)高達(dá) 。 每噸標(biāo)準(zhǔn)煤的產(chǎn)出率 ，我國(guó)相當(dāng)于美國(guó)的 %，歐盟的 %。日本的 %。 摘自中國(guó)城市環(huán)境衛(wèi)生協(xié)會(huì) 《 環(huán)衛(wèi)信息 》 Chapter 8: Profit Maximization and Competitive Supply 28 of 36 Copyright 169。 2022 Pearson Education, Inc. Publishing as Prentice Hall ? Microeconomics ? Pindyck/Rubinfeld, 7e. 對(duì)資源的定價(jià)能力低 ? 同濟(jì)大學(xué)教授：為什么我國(guó)作為鐵礦石的一個(gè)重要采購大國(guó)卻不具有對(duì)鐵礦石價(jià)格的議價(jià)權(quán)？ ? 回答： – 鐵礦石價(jià)格的談判歷史有 30~40年，中國(guó)進(jìn)入才 3年，談判規(guī)則是別人制定的，中國(guó)人目前只能執(zhí)行，處于不利地位。 – 價(jià)格談判是三家對(duì)三家，中、日、英對(duì)巴西、澳大利亞的三家大礦山，日、英產(chǎn)品的附加值高，對(duì)價(jià)格上漲的承受力高，成本價(jià)格上漲對(duì)其最終產(chǎn)品價(jià)格的影響只有 8%0， 它們也希望借價(jià)格上漲打壓中國(guó)企業(yè)，談判不出力 – 中國(guó)企業(yè)不團(tuán)結(jié)，一方面價(jià)格談判希望降價(jià)，另一方面有的企業(yè)又囤積購買，待價(jià)而沽，破壞談判 Chapter 8: Profit Maximization and Competitive Supply 29 of 36 Copyright 169。 2022 Pearson Education, Inc. Publishing as Prentice Hall ? Microeconomics ? Pindyck/Rubinfeld, 7e. P MC AC MC’ Q1 Q2 AC’ Chapter 8: Profit Maximization and Competitive Supply 30 of 36 Copyright 169。 2022 Pearson Education, Inc. Publishing as Prentice Hall ? Microeconomics ? Pindyck/Rubinfeld, 7e. THE SHORTRUN MARKET SUPPLY CURVE Industry Supply in the Short Run The shortrun industry supply curve is the summation of the supply curves of the individual firms. Because the third firm has a lower average variable cost curve than the first two firms, the market supply curve S begins at price P1 and follows the marginal cost curve of the third firm MC3 until price equals P2, when there is a kink. For P2 and all prices above it, the industry quantity supplied is the sum of the quantities supplied by each of the three firms. Figure Elasticity of Market Supply Es = (ΔQ/Q)/(ΔP/P) Chapter 8: Profit Maximization and Competitive Supply 31 of 36 Copyright 169。 2022 Pearson Education, Inc. Publishing as Prentice Hall ? Microeconomics ? Pindyck/Rubinfeld, 7e. 價(jià)格上升對(duì)行業(yè)供應(yīng)量的影響 ? 產(chǎn)品價(jià)格上升有兩種效應(yīng) ： – 產(chǎn)品供應(yīng)量增加 – 原材料成本上升， MC上升，供應(yīng)曲線內(nèi)移動(dòng)，供應(yīng)量降低（ 中國(guó)資源依賴型經(jīng)濟(jì)增長(zhǎng)帶動(dòng)原材料價(jià)格上漲，進(jìn)一步阻礙中國(guó)經(jīng)濟(jì)增長(zhǎng)） ? 行業(yè)供應(yīng)曲線反應(yīng)的是這兩者的中和 Chapter 8: Profit Maximization and Competitive Supply 32 of 36 Copyright 169。 2022 Pearson Education, Inc. Publishing as Prentice Hall ? Microeconomics ? Pindyck/Rubinfeld, 7e. THE SHORTRUN MARKET SUPPLY CURVE Table The World Copper Industry (2022) Country Australia Canada Chile Indonesia Peru Poland Russia US Zambia Country 950 600 5,400