How does trade make people better off?
Remember Alexander Selkirk? He was the castaway who inspired the story of Robinson Crusoe when he was stranded on a desert island in the early 1700s. Because Selkirk was alone and had no contact with the outside world. he had no chance to improve his standard of living through trade.
Suppose. however. that a second castaway. Pirate Jack. washed up on the island one day. Now Selkirk would not only have someone to talk to; he would also have a potential trading partner. But would trade make life better for either Selkirk or Pirate Jack? To find out. consider the following scenario.
Shortly after Pirate Jack’s arrival. Selkirk tells him about the island’s two main economic activities: gathering wild turnips and digging clams. Right away. the castaways face a critical question: would they be better off working separately and fending for themselves or joining forces and working together’
As it turns out. Pirate Jack is a more efficient worker than Selkirk. He is younger. stronger. and better at almost everything. including gathering turnips and digging clams. As a result. he enjoys an absolute advantage in food production.
Figure 4.3A shows how many turnips and clams each castaway is able to collect in a given amount of time. Selkirk can gather 10 turnips or dig 10 clams in one hour, for a total of 40 turnips or 40 clams in a four-hour workday. Pirate Jack can gather 30 turnips or dig 15 clams in an hour. In four hours, he can collect 120 turnips or 60 clams.
At first, the two men decide to work together and equally share the food they produce. Pirate Jack soon begins to wonder, however, whether he might be better off moving to the other side of the island and working for himself. Based on his absolute advantage as a food producer, he concludes that it is in his interest to go it alone. At the time, three centuries ago, most people would have agreed with Pirate Jack’s decision.
A century later, however. new economic insights might have led Pirate Jack to a different conclusion. Those insights came from the pioneering work of the English economist David Ricardo, who, in 1817, developed the theory of comparative advantage.
Comparative advantage is defined as the ability to perform a task at a lower opportunity cost than someone else is able to perform that task. Opportunity cost. you will remember. is the value of what you give lip to do something. As a producer, you have an absolute advantage if the time and labor required for you to produce something is less than it is for another producer. But you have a comparative advantage if your opportunity cost is less than another producer’s opportunity cost. Ricardo’s breakthrough was to see that, regardless of absolute advantage, people could benefit from specializing in those activities in which they had a comparative advantage.
Ricardo developed this principle in response to new English import tariffs known as Corn Laws. These tariffs placed a tax on imported grain in order to raise its price and protect English grain growers. who could not compete with cheaper foreign grain. This tariff helped farmers and wealthy landowners. But it hurt factory workers, who could not grow their own food and had to pay more for their bread.
Ricardo argued that allowing cheap grain to enter England would force the English to cut back on grain production and to instead concentrate their resources on manufacturing. which was increasingly where their advantage lay. In other words, English producers should specialize in goods in which they had a comparative advantage and then trade with foreign producers. The results, Ricardo said, would benefit society as a whole.
The production possibilities frontiers (PPFs) in Figure 4.3B show how Ricardo’s theory can be applied to Selkirk and Pirate Jack. Remember that a PPF shows how much of two products or services a person or an economy can produce in a given amount of time.
Selkirk’s PPF shows that he can produce 40 turnips or 40 clams in four hours. If he divides his time between the two activities, he can produce a combination of turnips and clams in varying amounts. For example, Point A on the graph indicates that Selkirk can collect 20 turnips and 20 clams in a typical workday.
According to Pirate Jack’s PPF, in addition to his daily rate of 120 turnips or 60 clams, he can produce mixed quantities, such as 90 turnips and 15 clams. This mixed quantity is represented by Point B.
The PPFs clearly show Pirate Jack’s absolute advantage in food production. But do they indicate any comparative advantage for either Selkirk or Pirate Jack? To answer this question, We must first calculate the opportunity cost associated with each activity.
Selkirk’s data show that for every 10 turnips he gathers, he gives up the opportunity to dig 10 clams. So his opportunity cost for each turnip is 1 clam, and his opportunity cost for each clam is 1 turnip.
Pirate Jack has different opportunity costs. For every 30 turnips he gathers, he gives up the opportunity to dig 15 clams. That means that Pirate Jack’s opportunity cost for each turnip is t clam, while his opportunity cost for each clam is 2 turnips. The opportunity costs for both men are shown in Figure 4,3C.
As Figure 4.3C shows, Pirate Jack’s opportunity cost for gathering turnips is lower than Selkirk’s: 1/2 clam for Pirate Jack versus 1 clam for Selkirk. This gives Pirate Jack a comparative advantage over Selkirk in gathering turnips. On the other hand, Selkirk’s opportunity cost for digging clams is lower: I turnip for Selkirk versus 2 turnips for Pirate Jack. This means that Selkirk has a comparative advantage over Pirate Jack in digging clams, even though he does not have an absolute advantage.
According to Ricardo’s theory, Selkirk and Pirate Jack should each specialize in the activity in which he has a comparative advantage. That would mean that Selkirk should dig clams and Pirate Jack should gather turnips. They could then trade with each other to obtain the product they do not produce. But would this arrangement work to their benefit?
The table in Figure 4.3D shows how each castaway might gain from trading based on comparative advantage. The first two columns of data provide production and consumption values for both men if they do not specialize and trade. These columns contain the values represented by Points A and B from Figure 4.3D.
The next two columns show production and consumption values if the castaways agree to specialize and then trade 17 clams for 25 turnips. The production values show how much each man can produce by specializing, The consumption values indicate how much of both products the men could have if they then traded with each other.
The last column shows what each man has gained from this trade, Selkirk now has the 25 turnips he got from Pirate Jack, along with the 23 clams he did not trade. His decision to trade has resulted in a gain of 5 turnips and 3 clams.
As for Pirate Jack, after trading 25 turnips to Selkirk, he still has 95 left, 5 more than he would have had if had chosen to go it alone. He also has the 17 clams he got from Selkirk, 2 more than he would have had without trade, So both castaways have gained from specialization and trade.
The PPFs in Figure 4.3E show the original production possibilities for the castaways, along with the increased amounts they receive through trade. Those new amounts, represented by Points A’ and B: sit outside the PPF curve, thus indicating the gains the castaways have made as a result of trade.
What is true for individuals is also true for nations, including the United States, When the principle of comparative advantage is allowed to guide who produces what — for example, Florida farmers growing oranges and Idaho farmers growing potatoes — society usually benefits.
Some of the factors that give rise to comparative advantage. such as climate and natural resources, may be fairly obvious. The main reason Florida has an advantage over Idaho in orange production is that oranges grow better in war m climates. Likewise. Nevada has a comparative advantage in gold production because of its gold deposits. Saudi Arabia excels in oil production because of its abundant oil reserves, while Canada can exploit its vast forests to produce timber. When it comes to farming, mining, forestry, and fishing, geography determines where comparative advantage lies.
Other factors — including education, wage levels, and technology differences — also play a role in determining comparative advantage. The United States, with its many colleges and universities, has a highly skilled, high-wage workforce. This gives the United States a comparative advantage in the development of advanced technologies, such as computer systems. Less-developed nations, on the other hand, tend to have relatively unskilled, low-wage work forces. Such countries often have a comparative advantage in the production of assembly-line goods, like clothing, that do not require highly skilled labor.
The beauty of comparative advantage, as economists see it, is that it stands to benefit all trading partners. Countries that seem to have it all-abundant natural resources, high human capital-can actually gain more by specializing in what they do best and trading with other countries. But even countries with no absolute advantages can come out ahead by finding what they can produce at a lower opportunity cost than other countries — their comparative advantage — and trading.
