This is “The Microeconomic Approach”, section 2.2 from the book Theory and Applications of Microeconomics (v. 1.0).
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There are several distinguishing features of the microeconomic approach to the world. We discuss them briefly and then conclude with a look at the big questions of economics.
One element of the microeconomic approach is individual choice. Throughout this book, we explore how individuals make decisions. Economists typically suppose that individuals make choices to pursue their (broadly defined) self-interest given the incentives that they face.
We look at individuals in their roles both as members of households and as members of firms. Individuals in households buy goods and services from other households and—for the most part—firms. They also sell their labor time, mostly to firms. Managers of firms, meanwhile, make decisions in the effort to make their firms profitable. By the end of the book, we will have several frameworks for understanding the behavior of both households and firms.
Individuals look at the prices of different goods and services in the economy when deciding what to buy. They act in their own self-interest when they purchase goods and services: it would be foolish for them to buy things that they don’t want. As prices change, individuals respond by changing their decisions about which products to buy. If your local sandwich store has a special on a breakfast bagel today, you are more likely to buy that sandwich. If you are contemplating buying an Android tablet computer but think it is about to be reduced in price, you will wait until the price comes down.
Just as consumers look at the prices they face, so do the managers of firms. Managers look at the wages they must pay, the costs of the raw materials they must purchase, and so on. They also look at the willingness of consumers to buy the products that they are selling. Based on all this information, they decide how much to produce and what to buy. Your breakfast bagel may be on special because the owner of your local sandwich shop got a good deal on bagels from the supplier. So the owner thinks that breakfast bagels can be particularly profitable, and to sell a lot of them, she sets a lower price than normal.
The buying and selling of a bagel may seem trivial, but similar factors apply to much bigger decisions. Potential students think about the costs and benefits of attending college relative to getting a full-time job. For some people, the best thing to do is to work full time. For others, it is better to go to school full time. Yet others choose to go to school part time and work part time as well. Presumably your own decision—whichever of these it may be—is one you made in your own best interests given your own specific situation.
From this discussion, you may think that economics is all about money, but economists recognize that much more than money matters. We care about how we spend our time. We care about the quality of the air we breathe. We care about our friends and family. We care about what others think of us. We care about our own self-image: what sort of a person am I? Such factors are harder to measure and quantify, but they all play a role in the decisions we make.
A second element of microeconomics has to do with how individual choices are interconnected. Economics is partly about how we make decisions as individuals and partly about how we interact with one another. Most importantly—but not exclusively—economics looks at how people interact by purchasing and selling goods and services.
In a typical transaction, one person (the buyer) hands over money to another (the seller). In return, the seller delivers something (a good or a service) to the buyer. For example, if you buy a chocolate bar for a dollar, then a dollar bill goes from your hands to those of the seller, and a chocolate bar goes from the seller to you. At the level of an individual transaction, this sounds simple enough. But the devil is in the details. In any given (potential) transaction, we can ask the following questions:
You will see in different chapters of this book that the answers to these questions depend on exactly how buyers and sellers interact. We get a different answer depending on whether there are many sellers or only a few. We get a different answer if the good is sold at a retail store or at an auction. We get a different answer if buyers and sellers can or cannot negotiate. The exact way in which people exchange goods and services matters a great deal for the how many? and how much? questions and thus for the gains from trade in the economy.
We have pointed out that individuals acting in their own self-interest benefit from voluntary trade. If you are not forced to buy or sell, then there is a presumption that every transaction makes the participants happier. What is more, markets are often a very effective institution for allowing people to meet and trade with one another. In fact, there is a remarkable result in economics that—under some circumstances—individuals acting in their own self-interest and trading in markets can manage to obtain all the possible benefits that can come from trading. Every transaction carried out is for the good, and every good transaction is carried out. From this comes a powerful recommendation: do whatever is possible to encourage trade. The phrase under some circumstances is not a minor footnote. In the real world, transactions often affect people other than the buyer and the seller, as we saw in our example of gas stations in Mexico City. In other cases, there can be problems with the way that markets operate. If there is only a small number of firms in a market, then managers may be able to set high prices, even if it means that people miss out on some of the benefits of trade. Later in this book, we study exactly how managers make these decisions. The microeconomic arguments for government intervention in the economy stem from these kinds of problems with markets. In many chapters, we discuss how governments intervene in an attempt to improve the outcome that markets give us. Yet it is often unclear whether and how governments should be involved. Pollution in Mexico City illustrates how complex these problems can be. First, who is responsible for the pollution? Some of it comes from people and firms outside the city and perhaps even outside the country. If pollution in Mexico City is in part caused by factories in Texas, who should deal with the problem: the Mexico City government, the Mexican government, the US government, or the Texas state legislature? Second, how much pollution should we tolerate? We could shut down all factories and ban all cars, but few people would think this is a sensible policy. Third, what measures can we use to combat air pollution? Should we simply place limits on production by firms and the amount of driving? Should we use some kind of tax? Is there a way in which we can take advantage of our belief that people, including the managers of firms, respond to incentives?
There are two traps that we must avoid. The first is to believe that markets are the solution to everything. There is no imaginable market in which the residents of Mexico City can trade with the buyers and sellers of gasoline to purchase the right amount of clean air. The second trap is to believe that the government can fix every market failure. Governments are collections of individuals who respond to their own incentives. They can sometimes make things better, but they can sometimes make things worse as well.
There is room for lots of disagreement in the middle. Some economists think that problems with markets are pervasive and that government can do a great deal to fix these problems. Others think that such problems are rare and that governmental intervention often does more harm than good. These disagreements result partly from different interpretations of the evidence and partly from differences in politics. Economists are as prone as everyone else to view the world through their own ideological lens. As we proceed, we do our best to present the arguments on controversial issues and help you understand why even economists sometimes come to differing conclusions about economic policy.
Perhaps our story of the Barbados-Grenada soccer game did not seem related to economics. Economists believe, though, that the decisions we make reflect the incentives we face. Behavior that seems strange—such as deliberately scoring an own goal in a soccer game—can make perfect sense once you understand the underlying incentives. In the economic world, it is often governments that make the rules of the game; like the organizers of soccer tournaments, governments need to be careful about how the rules they set can change people’s behavior.
Here is an example. In some European countries, laws are in place that give a lot of protection to workers and keep them from being unfairly fired by their employers. The intentions of these laws are good; some of their consequences are not so beneficial. The laws also make firms more reluctant to hire workers because they are worried about being stuck with an unsuitable employee. Thus these laws probably contribute to higher unemployment.
Incentives affect all transactions. When you buy a breakfast bagel on sale, both you and the owner of the sandwich shop are responding to the incentives that you face. The owner responds to the lower price of bagels. You respond to the lower price of the sandwich. Economists think that we can understand a great deal about people’s behavior if we have a good understanding of the incentives that they face.
Notice that not everyone makes the same choices. There are two main reasons for this:
To conclude our introduction to microeconomics, let us look at the big picture of what happens in an economy. An economy possesses some resources. These include the time and abilities of the people who live in the economy, as well as natural resources such as land, mineral deposits, and so on. An economy also possesses some technologies. A technology is a means of changing, or transforming, one set of things into other things. For example, we have a technology for making tea. This technology takes cold water, energy, and dried leaves and transforms them into a hot beverage. Finally, an economy, of course, contains its people, and these people like to consume things. Economics studies all aspects of this process. It considers the following:
These questions concern the allocation of resources.
The what in the first question reflects the choice among the multitude of goods and services an economy could produce. Think for a moment about the clothes you are wearing right now, the food you have eaten today, and the activities you undertake during a typical day. Someone made those clothes; someone prepared that food. Somehow, society must decide how much of each type of good and service to produce.
The how in the second question reflects competing ways to produce goods and services. Take a basic commodity such as rice. A large amount of rice is produced in the United States on large-scale, mechanized farms. A large amount of rice is also produced in Vietnam, but the production methods are very different. In Vietnam, people do much more work manually rather than by machine. A big part of the how question is deciding what mix of resources and what technologies should be used to produce goods and services. The answer in a rich country such as the United States is frequently different from the answer in a poor country such as Vietnam. Indeed, the answer may be different in different states in the United States or in the same place at different times.
The who in the third question concerns the distribution of goods and services in the economy. Suppose you were responsible for the distribution of all goods and services to your family. If there are 4 people in your family and each consumed 50 products in a typical day, you would have to make about 200 allocation decisions each day. It would be a very hard task. Yet somehow the economies of the world allocate billions of products to billions of people.
These three questions are answered in the world partly through individual decisions. The way in which you allocate your time each day is part of the allocation of resources in the economy. If each of us lived alone, engaging in subsistence farming and not interacting with others, then we would each determine our own allocation of resources. Because we interact with others, however, these questions are also answered in part by the way in which society is organized. Most of us produce only a few goods but consume many. We specialize in production and generalize in consumption. To do so, we must exchange what we produce with others. Most of these exchanges take place as a result of individual decisions in different kinds of markets. It is the operation of these countless markets that determines the allocation of goods and services in the economy. Remarkably, these markets somehow coordinate the decisions of the billions of people in the world economy.
Some of these exchanges are controlled by the government. In some economies, the government plays a very active role; in others, it intervenes less. When a government makes decisions about the allocation of resources, this is another mechanism in the production of goods and the distribution to individuals.