1、經濟及兩大經濟學領域
Economics is a social science that studies the production, distribution, trade and consumption of goods and services.
Economics, which focuses on measurable variables, is broadly divided into two main branches: microeconomics, which deals with individual agents, such as households and businesses, and macroeconomics, which considers the economy as a whole, in which case it considers aggregate supply and demand for money, capital and commodities. Aspects receiving particular attention in economics are resource allocation, production, distribution, trade, and competition. Economic logic is increasingly applied to any problem that involves choice under scarcity or determining economic value. Mainstream economics focuses on how prices reflect supply and demand, and uses equations to predict consequences of decisions.
2、兩大經濟製度I：資本主義經濟體係
It is useful to think of the economy of a nation as tending toward one or the other of two major theoretical models. At one theoretical extreme is the purely capitalist system, which assumes that free competition produces the best allocation of scarce resources, the greatest productivity and efficiency, and the lowest costs. Decisions about who does what and who gets what are made naturally as consumers and businesses interact in the marketplace, where prices are strongly influenced by how much something costs to make or do and how much people are willing to pay for it. Most enterprises are initiated by individuals or voluntary groups of people. When more resources are needed than are available to any one person （such as to build a factory）, they may be obtained from other people, either by taking out loans from banks or by selling ownership shares of the business to other people. High personal motivation to compete requires private ownership of productive resources （such as land, factories, and ships） and minimal government interference with production or trade. According to capitalist theory, individual initiative, talent, and hard work are rewarded with success and wealth, and individual political and economic rights are protected.
3、兩大經濟製度II：社會主義經濟體係
At the other theoretical extreme is the purely socialist system, which assumes that the wisest and fairest allocation of resources is achieved through government planning of what is produced and who gets it at what cost. Most enterprises are initiated and financed by the government. All resources of production are owned by the state, on the assumption that private ownership causes greed and leads to the exploitation of workers by owners. According to socialist theory, people contribute their work and talents to society not for personal gain but for the social good; and the government provides benefits for people fairly, on the basis of their relative needs, not their talent and effort. The welfare of the society as a whole is regarded as being more important than the rights of any individuals.
There are, however, no nations with economic systems at either the capitalist or the socialist extreme; rather, the world’s countries have at least some elements of both. Such a mixture is understandable in practical terms.
4、福利經濟學的概念
Welfare economics is a branch of economics that uses microeconomic techniques to simultaneously determine allocative efficiency within an economy and the income distribution associated with it. It analyzes social welfare, however measured, in terms of economic activities of the individuals that comprise the theoretical society considered. As such, individuals, with associated economic activities, are the basic units for aggregating to social welfare, whether of a group, a community, or a society, and there is no “social welfare” apart from the “welfare” associated with its individual units. Here, “welfare” in its most general sense refers to well-being.
5、社會福利及其兩大測量方式
Social welfare refers to the overall welfare of society. With sufficiently strong assumptions, it can be specified as the summation of the welfare of all the individuals in the society. Welfare may be measured either cardinally in terms of “utils” or dollars, or measured ordinally in terms of Pareto efficiency. The cardinal method in “utils” is seldom used in pure theory today because of aggregation problems that make the meaning of the method doubtful, except on widely challenged underlying assumptions. In applied welfare economics, such as in cost-benefit analysis, money-value estimates are often used, particularly where income-distribution effects are factored into the analysis or seem unlikely to undercut the analysis.
There are two sides to welfare economics: economic efficiency and income distribution. Economic efficiency is largely positive and deals with the “size of the pie”. Income distribution is much more normative and deals with “dividing up the pie”.
6、貿易
Trade is the voluntary exchange of goods, services, or both, and a form of economics. A mechanism that allows trade is called a market. The original form of trade was barter, the direct exchange of goods and services. Modern traders instead generally negotiate through a medium of exchange, such as money. As a result, buying can be separated from selling, or earning. The invention of money （and later credit, paper money and non-physical money） greatly simplified and promoted trade.
Trade exists for many reasons. Because of specialization and division of labor, most people concentrate on a small aspect of manufacturing or service, trading their labor for products. Trade exists between regions because different regions have an absolute or comparative advantage in the production of some tradable commodity, or because different regions’ size allows for the benefits of mass production.
7、社會福利函數
The social welfare function is a way of mathematically stating the relative importance of the individuals that comprise society.
A utilitarian welfare function （also called a Benthamite welfare function） sums the utility of each individual in order to obtain society’s overall welfare. All people are treated the same, regardless of their initial level of utility. One extra unit of utility for a starving person is not seen to be of any greater value than an extra unit of utility for a millionaire. At the other extreme is the Max-Min function. According to the Max-Min criterion, welfare is maximized when the utility of those society members that have the least is the greatest. No economic activity will increase social welfare unless it improves the position of the society member that is the worst off. Most economists specify social welfare functions that are intermediate between these two extremes.
The social welfare function is typically translated into social indifference curves so that they can be used in the same graphic space as the other functions that they interact with. A utilitarian social indifference curve is linear and downward sloping to the right. The Max-Min social indifference curve takes the shape of two straight lines joined so as they form a 90degree angle. A social indifference curve drawn from an intermediate social welfare function is a curve that slopes downward to the right.
8、公共財政的三大必要性
1.Governments provide public goods—government-financed items and services such as roads, military forces, lighthouses, and street lights. Private citizens would not voluntarily pay for these services, and therefore businesses have no incentive to produce them.
2.Public finance also enables governments to correct or offset undesirable side effects of a market economy. These side effects are called spillovers or externalities. For example, households and industries may generate pollution and release it into the environment without considering the adverse effect pollution has on others. If it costs less to pollute than not to, people and businesses have a financial incentive to continue polluting. Pollution is a spillover because it affects people who are not responsible for it. To correct a spillover, governments can encourage or restrict certain activities. For example, governments can sponsor recycling programs to encourage less pollution, pass laws that restrict pollution, or impose charges or taxes on activities that cause pollution.
3.Public finance provides government programs that moderate the incomes of the wealthy and the poor. These programs include social security, welfare, and other social programs. For example, some elderly people or people with disabilities require financial assistance because they cannot work. Governments redistribute income by collecting taxes from their wealthier citizens to provide resources for their needy ones. The taxes fund programs that help support people with low incomes.
9、政府花費的兩大形式
Government spending takes two forms: exhaustive spending and transfer spending. Exhaustive spending refers to purchases made by a government for the production of public goods. For example, to construct a new harbor the government buys and uses resources from the economy, such as labor and raw materials. In transfer spending the government transfers income to people to help them support themselves. Transfers can be one of two kinds: cash or in-kind. Cash transfers are cash payments, such as social security checks and welfare payments. In-kind transfers involve no cash payments but instead transfer goods or services to recipients. Examples of in-kind transfers include food stamp coupons and Medicare. Recipients of food stamp coupons exchange the coupons for groceries.
10、政府預算
Each year national, state, and local governments create a budget to determine how much money they will spend during the upcoming year. The budget determines which public goods to produce, which spillovers to correct, and how much assistance to provide to financially disadvantaged people. The chief administrator of the government—such as the president, prime minister, governor, or mayor—proposes the budget. However, the legislature—such as the congress, parliament, state legislature, or city council—ultimately must pass the budget. The legislature often changes the size and composition of the budget, but it must not make changes that the chief administrator will reject and veto.