一些经济学术语及其它（一）Cold snap寒潮、寒流（可数）There is no auctioneer calling out the price of ice creaman ice-cream conecompetitive market：a market in which there are many buyers and many sellers so that each has a negligible impact on the market priceprice takers：those who have no impact on price but can only accept the pricePerfectly competitive markets 竞争充分市场One such market, called an oligopoly （寡头市场）, has a few sellers that do not always compete aggressivelylaw of demand：the claim that, other things equal, the quantity demanded of a good falls when the price of the good riseslaw of supply：the claim that, other things equal, the quantity supplied of a good rises when the price of the good risesnormal good （正常商品）：a good for which, other things equal, an increase in income leads to an increase in demandinferior good ( 劣质商品)：a good for which, other things equal, an increase in income leads to a decrease in demands ubstitutes（替代品）：two goods for which an increase in the price of one leads to an increase in the demand for the othercomplements（互补品）：two goods for which an increase in the price of one leads to a decrease in the demand for the otherhot fudge 热巧克力demand schedule：a table that shows the relationship between the price of a good and the quantity demandedsupply schedule：a table that shows the relationship between the price of a good and the quantity suppliedceteris paribus（其它条件不变）：a Latin phrase, translated as “other things being equal,” used as are minder that all variables other than the ones being studied are assumed to be constantA 10 percent increase in the price causes a 12 percent drop in teenage smoking （这句话让我说肯定是in smoking among teenagers）At an even lower price, you may choose to go out of business altogether (这个词的用法以前没怎么注意，此处可以翻译为“直接”)Equilibrium：a situation in which supply and demand have been brought into balanceequilibrium price：the price that balances supply and demandequilibrium quantity：the quantity supplied and the quantity demanded when the price has adjusted to balance supply and demandThe equilibrium price is sometimes called the market-clearing price（市场出清价格）because, at this price, everyone in the market has been satisfied: Buyers have bought all they want to buy, and sellers have sold all they want to sellThere is no upward or downward pressure on the price （价格没有上升或者下降的压力，就是这么表达的）law of supply and demand：the claim that the price of any good adjusts to bring the supply and demand for that good into balanceshortage：a situation in which quantity demanded is greater than quantity suppliedsurplus：a situation in which quantity supplied is greater than quantity demanded一些经济学术语及其它（二）Elasticity弹性a measure of the responsiveness of quantity demanded or quantity supplied to one of its determinantsprice elasticity of demand需求的价格弹性a measure of how much the quantity demanded of a good responds to a change in the price of that good, computed as the percentage change in quantity demanded divided by the percentage change in priceincome elasticity of demand 需求的收入弹性a measure of how much the quantity demanded of a good responds to a change in consumers’ income, computed as the percentage change in quantity demanded divided by the percentage change in incomecross-price elasticity of demand需求交叉价格弹性a measure of how much the quantity demanded of one good responds to a change in the price of another good, computed as the percentage change in quantity demanded of the first good divided by the percentage change in the price of the second good price elasticity of supply 供给的价格弹性a measure of how much the quantity supplied of a good responds to a change in the price of that good, computed as the percentage change in quantity supplied divided by the percentage change in priceDemand for a good is said to be elastic if the quantity demanded responds substantially to changes in the price. Demand is said to be inelastic if the quantity demanded responds only slightly to changes in the price.midpoint method 中点法经济学中计算弹性的一种方法elastic demand 弹性需求inelastic demand 非弹性需求price ceiling 最高限价a legal maximum on the price at which a good can be sold (impose a price ceiling/floor)price floor 最低限价a legal minimum on the price at which a good can be soldWhen the government imposes a binding price ceiling on a competitive market, a shortage of the good arises, and sellers must ration the scarce goods among the large number of potential buyers.tax incidence 税收归宿the study of who bears the burden of taxationpayroll tax: 工资税A tax burden falls more heavily on the side of the market that is less elastic.一些经济学术语及其它（三）welfare economics 福利经济学the study of how the allocation of resources affects economic well-being willingness to pay 支付意愿the maximum amount that a buyer will pay for a goodconsumer surplus 消费者剩余a buyer’s willingness to pay minus the amount the buyer actually pays producer surplus生产者剩余the amount a seller is paid for a good minus the seller’s costmarginal buyer 边际买家the buyer who would leave the market first if the price were any higher marginal seller 边际卖家the seller who would leave the market first if the price were any lower efficiency效率the property of a resource allocation of maximizing the total surplus received by all members of societyequity公平the fairness of the distribution of well-being among the members of societyIn some markets, a single buyer or seller (or a small group of them) may be able to control market prices. This ability to influence prices is called market power 市场势力.market failure市场失灵—the inability of some unregulated markets to allocate resources efficiently deadweight loss无谓损失/社会净损失the fall in total surplus that results from a market distortion, such as a taxTaxes cause deadweight losses because they prevent buyers and sellers from realizing some of the gains from trade.The greater the elastic cities of supply and demand, the greater the deadweight loss of a tax.marginal tax rate 边际税率underground economy 地下经济Laffer curve拉弗曲线supply-side economics 供应经济学一些经济学术语及其它（十）Economists call this situation imperfect competition不完全竞争Oligopoly 寡头垄断a market structure in which only a few sellers offer similar or identical productsThe essence of an oligopolistic market 寡头市场 is that there are only a few sellers. As a result, the actions of any one seller in the market can have a large impact on the profits of all the other sellers monopolistic competition垄断竞争a market structure in which many firms sell products that are similar but not identicaloligopolistic market寡头市场oligopolist寡头duopoly双寡头垄断collusion串通an agreement among firms in a market about quantities to produce or prices to chargecartel卡塔尔/垄断联盟a group of firms acting in unisonNash equilibrium 纳什均衡a situation in which economic actors interacting with one another each choose their best strategy given the strategies that all the other actor shave chosengame theory博弈论the study of how people behave in strategic situationsprisoners’dilemma囚徒困境a particular “game”between two captured prisoners that illustrates why cooperation is difficult to maintain even when it is mutually beneficialdominant strategy优势策略a strategy that is best for a player in a game regardless of the strategies chosen by the other playersresale price maintenance转售价格维持fair trade公平交易predatory pricing掠夺性定价 a pricing strategy intended to force competitors out of market with a short-term big price cut in order to gain a monopoly position in the long term.Tying搭售Over time, Microsoft has added many features to Windows that were previously stand-alone products 单独销售产品一些经济学术语及其它（九）While a competitive firm is a price taker价格接受者, a monopoly firm is a price maker 价格制定者A firm is a monopoly/monopolist 垄断者if it is the sole seller of its product and if its product does not have close substitutes.The fundamental cause of monopoly is barriers to entry 进入壁垒An industry is a natural monopoly自然垄断when a single firm can supply a good or service to an entire market at a smaller cost than could two or more firms.In competitive markets 竞争性市场, price equals marginal cost. In monopolized markets 垄断性市场, price exceeds marginal cost.Sometimes companies merge not to reduce competition but to lower costs through more efficient joint production. These benefits from mergers are sometimes called synergies 协同效应Yet in many cases firms try to sell the same good to different customers for different prices, even though the costs of producing for the two customers are the same. This practice is called price discrimination 价格歧视.To understand why a monopolist would want to price discriminateIn particular, one such force is arbitrage 套利, the process of buying a good in one market at a low price and selling it in another market at a higher price in order to profit from the price difference.We begin by assuming that the monopolist can price discriminate perfectly. Perfect price discrimination 完全价格歧视describes a situation in which the monopolist knows exactly the willingness to pay of each customer and can charge each customer a different price.一些经济学术语及其它（八）water-efficient shower heads 莲蓬头competitive market 竞争性市场a market with many buyers and sellers trading identical products so that each buyer and seller is a price takereach seller can sell all he wants at the going price 现行价格To keep matters concrete, let’s consider a specific firmaverage revenue 平均收益total revenue divided by the quantity soldmarginal revenue 边际收益the change in total revenue from an additional unit soldAt the profit-maximizing level of output, marginal revenue and marginal cost are exactly equalthe land lies fallow 休耕sunk cost 沉没成本a cost that has already been committed and cannot be recoveredshutdown 歇业exit 退出一些经济学术语及其它（七）total revenue总收益 the amount a firm receives for the sale of its outputtotal cost 总成本the market value of the inputs a firm uses in productionexplicit costs显性成本input costs that require an outlay of money by the firmimplicit costs隐性成本input costs that do not require an outlay of money by the firmeconomic profit经济利润total revenue minus total cost, including both explicit and implicit costs accounting profit 会计利润total revenue minus total explicit costproduction function 生产函数the relationship between quantity of inputs used to make a good and the quantity of output of that goodmarginal product 边际产量the increase in output that arises from an additional unit of input diminishing marginal product 边际产量递减the property whereby the marginal product of an input declines as the quantity of the input increasesfixed costs固定成本costs that do not vary with the quantity of output producedvariable costs 可变成本costs that do vary with the quantity of output producedaverage total cost 平均总成本total cost divided by the quantity of outputaverage fixed cost 平均固定成本fixed costs divided by the quantity of outputaverage variable cost 平均可变成本variable costs divided by the quantity of outputmarginal cost 边际成本the increase in total cost that arises from an extra unit of productionefficient scale有效规模 the quantity of output that minimizes average total costaverage total cost is high because the fixed cost is spread 分摊 over only a few unitseconomies of scale 规模经济the property whereby long-run average total cost falls as the quantity of output increasesdiseconomies of scale 规模不经济the property whereby long-run average total cost rises as the quantity of output increasesconstant returns to scale规模报酬不变the property whereby long-run average total cost stays the same as the quantity of output changes一些经济学术语及其它（六）1. Today, all taxes taken together—including personal income taxes, corporate income taxes, payroll taxes, sales taxes, and property taxes—use up about a third of the average American’s income2. In many European countries, the tax bite is even larger.3. The family’s tax liability (how much it owes) is then based on its total income.4. charitable donation/giving 慈善捐款6. When the government runs a budget surplus, it uses the excess receipts to reduce its outstanding debts7. average tax rate 平均税率total taxes paid divided by total income9. marginal tax rate 边际税率the extra taxes paid on an additional dollar of income10. benefits principle 受益原则the idea that people should pay taxes based on the benefits they receive from government services11. vertical equity 纵向公平the idea that taxpayers with a greater ability to pay taxes should pay larger amounts12. horizontal equity 横向公平the idea that taxpayers with similar abilities to pay taxes should pay the same amount13. proportional tax 比例税a tax for which high-income and low-income taxpayers pay the same fraction of income14. regressive tax 累退税a tax for which high-income taxpayers pay a smaller fraction of their income than do low-income taxpayers15. progressive tax 累进税a tax for which high-income taxpayers pay a larger fraction o their income than do low-income tax payers16. Would it be more fair to give the Smiths a tax break 税收减免 to help them offset their high medical expenses?17. flypaper theory 粘蝇纸理论of tax incidence. According to this theory, the burden of a tax, like a fly on flypaper, sticks wherever it first lands. This assumption, however, is rarely valid18. flat tax 单一税率一些经济学术语及其它（五）A moment’s thought （稍作思考）reveals a long list of goods that the songwriter could have had in mind Excludability 排他性the property of a good whereby a person can be prevented from using itRivalry 竞争性the property of a good whereby one person’s use diminishes other people’s useprivate goods 私人物品goods that are both excludable and rivalpublic goods 公共物品goods that are neither excludable nor rivalcommon resources 共有资源goods that are rival but not excludablenatural monopoly 自然垄断/自然独占excludable goods 排他性物品rival goods 竞争性物品toll road 收费公路free rider 搭便车者/免费享用公共物品者a person who receives the benefit of a good but avoids paying for itprofit-seeking firms tend to free ride （作动词用）on the knowledge created by otherscost-benefit analysis 成本效益分析a study that compares the costs and benefits to society of providing a public goodTragedy of the Commons 公地悲剧a parable that illustrates why common resources get used more than is desirable from the stand point of society as a whole一些经济学术语及其它（四）world price 世界价格the price of a good that prevails in the world market for that goodimport quota 进口配额 a limit on the quantity of a good that can be produced abroad and sold domesticallydeadweight loss 无谓损失/社会净损失：是指由于市场未处于最优运行状态而引起的社会成本, 也就是当偏离竞争均衡时, 所损失的消费者剩余和生产者剩余。