【正文】 數(shù)量 0 價格 Q1 (a) 小額稅 無謂損失 PB Q2 PS Figure 6 How Deadweight Loss and Tax Revenue Vary with the Size of the Tax Tax revenue Quantity 0 Price (b) Medium Tax PB Q2 PS Supply Demand Q1 Deadweight loss 圖 6. 無謂損失和稅收收入如何隨著稅收規(guī)模而變動 稅收收入 數(shù)量 0 價格 (b) 中額稅 PB Q2 PS 供給 需求 Q1 無謂損失 Figure 6 How Deadweight Loss and Tax Revenue Vary with the Size of the Tax Tax revenue Demand Supply Quantity 0 Price Q1 (c) Large Tax PB Q2 PS Deadweight loss 圖 6. 無謂損失和稅收收入如何隨著稅收規(guī)模而變動 稅收收入 需求 供給 數(shù)量 0 價格 Q1 (c) 大額稅 PB Q2 PS 無謂損失 169。 2023 Thomson SouthWestern DEADWEIGHT LOSS AND TAX REVENUE AS TAXES VARY ? For the small tax, tax revenue is small. ? As the size of the tax rises, tax revenue grows. ? But as the size of the tax continues to rise, tax revenue falls because the higher tax reduces the size of the market. 169。 2023 Thomson SouthWestern 無謂損失和稅收收入隨稅收變動而變動 ? 收小額稅時，稅收收入少。 ? 隨著稅收規(guī)模增加，稅收收入增加。 ? 但隨著稅收規(guī)模繼續(xù)增加，稅收收入反而減少，這是因為較高的稅收規(guī)模減少了更多的市場規(guī)模。 Figure 6 How Deadweight Loss and Tax Revenue Vary with the Size of a Tax (a) Deadweight Loss Deadweight Loss 0 Tax Size 圖 6. 無謂損失和稅收收入如何隨著稅收規(guī)模而變動 (a) 無謂損失 無謂損失 0 稅收規(guī)模 Figure 6 How Deadweight Loss and Tax Revenue Vary with the Size of a Tax (b) Revenue (the Laffer curve) Tax Revenue 0 Tax Size 圖 6. 無謂損失和稅收收入如何隨著稅收規(guī)模而變動 (b) 稅收收入（拉伐曲線） 稅收收入 0 稅收規(guī)模 169。 2023 Thomson SouthWestern DEADWEIGHT LOSS AND TAX REVENUE AS TAXES VARY ? As the size of a tax increases, its deadweight loss quickly gets larger. ? By contrast, tax revenue first rises with the size of a tax, but then, as the tax gets larger, the market shrinks so much that tax revenue starts to fall. 169。 2023 Thomson SouthWestern 無謂損失和稅收收入隨稅收變動而變動 ? 隨著稅收規(guī)模提高，無謂損失迅速增大。 ? 相反，隨著稅收規(guī)模提高，稅收收入先是增加，然后隨著稅收規(guī)模越來越大，市場規(guī)模收縮非常之大，以至于稅收收入開始減少。 Summary 169。 2023 Thomson SouthWestern ? A tax on a good reduces the welfare of buyers and sellers of the good, and the reduction in consumer and producer surplus usually exceeds the revenues raised by the government. ? The fall in total surplus—the sum of consumer surplus, producer surplus, and tax revenue — is called the deadweight loss of the tax. Summary 169。 2023 Thomson SouthWestern ? 向一種物品征稅減少了該物品買者與賣者的福利，而且消費者和生產者剩余的減少通常超過了政府籌集到的收入。 ? 總剩余（消費者剩余、生產者剩余和稅收收入之和）的減少被稱為稅收的無謂損失。 Summary 169。 2023 Thomson SouthWestern ? Taxes have a deadweight loss because they cause buyers to consume less and sellers to produce less. ? This change in behavior shrinks the size of the market below the level that maximizes total surplus. Summary 169。 2023 Thomson SouthWestern ? 稅收有無謂損失是因為它引起買者少消費和賣者少生產。 ? 這種行為變化使市場規(guī)?？s小到使總剩余最大化的水平之下。 Summary 169。 2023 Thomson SouthWestern ? As a tax grows larger, it distorts incentives more, and its deadweight loss grows larger. ? Tax revenue first rises with the size of a tax. ? Eventually, however, a larger tax reduces tax revenue because it reduces the size of the market. Summary 169。 2023 Thomson SouthWestern ? 隨著稅收增加，它對激勵的扭曲越來越大，而且無謂損失也越來越大。 ? 稅收收入起初隨著稅收規(guī)模增加而增加。 ? 但是，最終由于高稅收減少了市場規(guī)模，也就減少了稅收收入。 169。 2023 Thomson SouthWestern 應用：國際貿易 169。 2023 Thomson SouthWestern Application: International Trade ? What determines whether a country imports or exports a good? ? Who gains and who loses from free trade among countries? ? What are the arguments that people use to advocate trade restrictions? 169。 2023 Thomson SouthWestern 應用：國際貿易 ? 什么決定一個國家是否進口或 出口一種物品 ? ? 在國際自由貿易中誰獲 利誰虧損？ ? 人們用來支持貿易限制的 各種觀點是什么？ 169。 2023 Thomson SouthWestern THE DETERMINANTS OF TRADE ? Equilibrium Without Trade – Assume: ? A country is isolated from rest of the world and produces steel. ? The market for steel consists of the buyers and sellers in the country. ? No one in the country is allowed to import or export steel. 169。 2023 Thomson SouthWestern 貿易的決定因素 ? 沒有貿易時的均衡 –假定 : ? 一個生產鋼鐵的國家孤立于其他國家 ? 鋼鐵市場由這個國家的買者和賣者組成 ? 這個國家的如何人都不允許進口或出口鋼鐵 Figure 1 The Equilibrium without International Trade Consumer surplus Producer surplus Price of Steel 0 Quantity of Steel Domestic supply Domestic demand Equilibrium price Equilibrium quantity 圖 1. 沒有國際貿易時的均衡 鋼鐵的 價格 均衡價格 0 鋼鐵數(shù)量 均衡數(shù)量 國內供給 國內需求 生產者剩余 消費者剩余 169。 2023 Thomson SouthWestern The Equilibrium Without Trade ? Results: ? Domestic price adjusts to balance demand and supply. ? The sum of consumer and producer surplus measures the total benefits that buyers and sellers receive. 169。 2023 Thomson SouthWestern 沒有貿易時的均衡 ? 結果 : ? 國內價格調整使國內賣者的供給量與國內買者的需求量平衡。 ? 消費者剩余和生產者剩余的總和來衡量買者和賣者從鋼鐵市場上得到的總利益。 169。 2023 Thomson SouthWestern The World Price and Comparative Advantage 世界價格與比較優(yōu)勢 ? If the country decides to engage in international trade, will it be an importer or exporter of steel? ? 如果這個國家決定參與國際貿易，它將是鋼鐵進口國還是出口國？ 169。 2023 Thomson SouthWestern The World Price and Comparative Advantage ? The effects of free trade can be shown by paring the domestic price of a good without trade and the world price of the good. The world price refers to the price that prevails in the world market for that good. 169。 2023 Thomson SouthWestern 世界價格與比較優(yōu)勢 ? 自由貿易的效果可以從沒有貿易時國內物品價格與 世界價格 相比較中得到說明。 ? 世界價格 ——一種物品在世界市場上所流行的價格。 169。 2023 Thomson SouthWestern The World Price and Comparative Advantage ? If a country has a parative advantage, then ? the domestic price will be below the world price, and ? the country will be an exporter of the good. ? If the c