- How markets work — buyers and sellers
- Market failure — when markets get it wrong
- What governments do in an economy
Who decided how much bread to bake?
Tomorrow morning, a city of a million people will want breakfast. Some will want bread. Some will want rice, eggs, fruit or milk. Nobody in the city has a list of what each person wants. Nobody gives an order to the bakers, the farmers and the shopkeepers. Yet most shops will have most things, and not much will be thrown away.
So who decided how much bread to bake?
Most people's first answer is "someone must be in charge". In many places, for most goods, that answer is wrong. And in some countries, for a long time, it was exactly right: a government office really did decide how much bread to bake. This lecture is about that difference.
The last two lectures ended with a promise. Every economy must choose a point on its production possibility frontier, and decide how much to give up today for goods tomorrow. The last lecture said that some economies make these choices through prices, and others through a government plan, and that this lecture would ask how. Here is the answer.
Three questions every economy must answer
The first Economics lecture showed that resources are scarce, so every society must make choices. Those choices come down to three questions.
- What to produce? More bread or more rice? More hospitals or more cars? Goods for now or machines for later? This is the choice of a point on the frontier.
- How to produce it? With many workers and simple tools, or with few workers and many machines?
- For whom to produce it? Who gets the goods? Those who can pay the most? Everyone equally? Those who need them most?
An economic system is a country's way of answering these three questions. There are two very different ways to answer them, and every real country uses some of each.
The first answer: let prices decide
In a market economy, the three questions are answered by millions of buyers and sellers. Firms and farms are owned by private people. Each one decides for itself what to make and how. Each buyer decides what to buy with the money they have.
So how does anything fit together? Through prices. Here is an invented example with numbers.
In an invented town, a loaf of bread sells for $2.00. It costs a baker $1.60 to make, including flour, fuel and wages. Then a new school and a new factory open, and many more people want bread. The bread runs out early every day. Bakers notice, and they raise the price to $2.50.
Think first. What does each baker earn on a loaf, before and after?
Before: a loaf. After: a loaf. The reward for each loaf has more than doubled, from 40 cents to 90 cents.
Now follow what people do. Bakers bake more loaves, because each one earns more. A café that made cakes starts making bread too. Some buyers buy a little less bread, or switch to rice, because bread now costs more. Flour mills sell more flour, so they buy more wheat.
Check. Nobody gave a single order. One price change sent the same message to bakers, buyers and mills at once: "bread is scarcer than before". ✓
Look at what the price did. It did three jobs at once.
- It was a signal. It told everyone that bread was wanted more than before.
- It was a reward. Profit rewarded the bakers who made more of what people wanted. Economists call this the profit motive.
- It shared out the bread. While bread was short, it went to those who were willing and able to pay the higher price. This was one of the four ways of sharing out a scarce good in the first lecture: by price.
That is it. That is the whole idea of a market economy. Prices carry information, and profit gives people a reason to act on it. The three questions are answered by many small decisions, each made by someone who can see a price.
Now test the idea before you read on.
A long heatwave arrives in a market economy. Far more people want electric fans than usual. Who tells the shops to order more fans, and the factories to make more? Choose one, then read the explanation.
This box explains who tells shops and factories to supply more fans in a heatwave, in a market economy.
Nobody gives an order. Shelves empty quickly, so shops order more from the makers. Fans become scarcer, so their price rises. Higher prices mean more profit on each fan, so factories make more. The price and the empty shelves carry the message.
This is the surprise of a market. Order appears without anyone ordering it. But the same system has weaknesses, and they come from the same place. A market listens to money. A family with little money sends a weak signal, however great its need. And a market only makes things that can be sold. A road that everyone uses, or clean air, is hard to sell, so a market alone makes too little of it. A later lecture, on market failure, looks at these weaknesses closely.
The second answer: let a plan decide
In a planned economy, also called a command economy, the government answers the three questions. It owns the factories and farms. A central planning office decides what each one must produce, how many workers it gets, and where its goods go. Prices are set by the plan, and they do not change when a good runs short.
The Soviet Union ran its economy this way, from its first Five-Year Plan in 1928 until the country broke up in 1991.
A plan has a real strength. A government can move resources fast towards a goal it chooses. The last lecture showed that a country which puts more resources into capital goods can move its frontier out faster. Soviet planners did exactly this. They put enormous resources into steel, machines and power stations, and far fewer into consumer goods such as clothes and furniture. A market might never have chosen that point on the frontier. A plan could simply order it.
But a plan has two deep problems.
The first is information. A planning office must decide how much of every good to make: every size of shoe, every kind of bolt, every medicine. Tastes change. Harvests fail. A machine breaks in one city. By the time the news reaches the planners and the plan is changed, months may have passed. In a market, each of these changes shows up in a price within days.
The second is incentives. A factory manager in a plan is judged on meeting the target, not on pleasing buyers. If the target is "10 000 pairs of shoes", making 10 000 pairs in one easy size meets it. Nobody earns more by making what people actually want.
The result, in many planned economies, was a pattern of goods nobody wanted piling up while goods people wanted ran out. Because prices could not rise, the shortages showed up as queues and empty shelves instead. The Hungarian economist János Kornai, who lived and worked in a planned economy, called them "shortage economies". (Source: J. Kornai, Economics of Shortage, 1980.)
In a planned economy, the price of bread is fixed at a low level, and bread is short. In a market economy, bread is short too, and its price rises. In which economy can a poor family more easily buy bread?
Show the answer
It is not as simple as it looks. In the planned economy, the bread is cheap, but there is not enough of it. The family can buy bread only if it reaches the front of the queue before the bread runs out. So the bread goes to those who can spend the most time queuing, or who know the right people. In the market economy, the bread is on the shelf, but at a higher price, so the family may buy less. Neither system shares out a scarce good perfectly. They share it out in different ways: one by time and luck, the other by money. This is why most countries add something else, such as help for poorer families.
The model below shows the information problem as numbers. It is invented and deliberately simple.
In week 5, people in an invented town start to want 130 thousand loaves a week instead of 100 thousand. In the market, bakers see the price rise and add 10 thousand loaves a week until they catch up. In the plan, the price is fixed, and output changes only after the planners' next review, plus 2 weeks to organise it. Choose how often the planners review the plan.
Try:
This table shows an invented town where the bread people want rises from 100 to 130 thousand loaves a week in week 5. In the market, output rises by 10 thousand loaves a week from week 6 and catches up in week 8. In the plan, the price is fixed, and output changes 2 weeks after the first plan review in or after week 5. The last column is the bread people wanted but could not get, added up over the year.
| System | Output catches up in week | Bread short over the year (thousand loaves) |
|---|---|---|
| Market (the price rises at first) | 8 | 60 |
| Plan reviewed every 4 weeks | 10 | 150 |
| Plan reviewed every 13 weeks | 15 | 300 |
| Plan reviewed every 26 weeks | 28 | 690 |
| Plan reviewed once a year | not this year | 1 440 |
The less often the plan is reviewed, the longer the shortage lasts. In the market, the short weeks show up as a higher price. In the plan, they show up as queues and empty shelves.
You should have seen the plan's shortage grow as the reviews became less frequent. A market "reviews" the price of every good, every day, without any office doing the work. A planning office cannot do that for millions of goods. That is the information problem in one picture.
The real answer: almost every economy is mixed
No real country is a pure market economy, and no real country is purely planned. Even the Soviet Union had small private plots where farm families grew and sold food.
A mixed economy uses markets for most goods, and the government for some. The real question is not "market or plan?" It is "which goods, and how much of each?"
In most countries, markets supply most food, clothes, phones and haircuts. The government usually supplies defence, courts and most roads. Schools and hospitals are often a mix: public ones run by the government and private ones run as businesses.
Countries draw the line in different places. Singapore is an example of a market-based economy with a large government role in one area: housing. Its Housing and Development Board builds flats, and about 76% of residents lived in them in 2023. Most of these flats are sold to the families who live in them. (Source: Housing and Development Board, Key Statistics FY2023.) One country can lean towards the market for most goods and towards the plan for a few.
A real case: China lets farmers keep the extra
The situation. In 1978, China's farms were run as large collective teams under the plan. The team's grain went to the state at fixed prices, and members were paid in "work points", which depended little on how hard each person worked. Grain output had grown only slowly for years.
The policy. In late 1978, farmers in Anhui province began an experiment that was not yet allowed. The best-known story is from Xiaogang village, where a group of families secretly divided the team's land among households. Each household promised to deliver a fixed amount (a quota) to the state. It could keep or sell everything above that. The idea spread, and the government accepted it. By the end of 1983, about 94% of rural households farmed this way. In 1979, the state also raised the prices it paid for grain.
The prediction. The plan still took the quota. But every extra kilogram now belonged to the family that grew it. That is a market reward, like the baker's extra 50 cents. Economics predicts that people work harder, and choose seeds, fertiliser and crops more carefully, when they keep the result.
What happened.
| China | 1978 | 1984 |
|---|---|---|
| Grain output (million tonnes) | 304.8 | 407.3 |
| Grain per person (kg) | 319 | 396 |
Grain output rose by about a third in six years, about 5% a year, more than twice the rate before 1978. Grain per person rose by about 24%. (Sources: J. Y. Lin, "Rural Reforms and Agricultural Growth in China", American Economic Review, 1992; World Bank, Four Decades of Poverty Reduction in China, 2022; FAO, Land Reform 1998/2; University of California, Giannini Foundation report on China's grain output.)
Verdict. The prediction fits well, but not perfectly. Justin Yifu Lin studied the provinces one by one. He found that the new system explained about half of the growth in farm output from 1978 to 1984. Other studies put its share between about 30% and 50%. Higher state prices and much more fertiliser explain much of the rest. And after 1984, the jump stopped: grain output fell in 1985 and then grew slowly. A reward for effort gives a large, one-time gain. It does not keep growth going by itself. Even so, this was a strong test of the idea in this lecture. The same farmers, on the same land, produced far more once they kept the extra.
Notice what kind of change this was. China did not jump from a plan to a pure market. It added a market reward inside a plan: the quota stayed, and the extra was free. That is a mixed system, built one decision at a time.
Answer the three questions for school uniforms in three invented countries: Country A (market), Country B (planned) and Country C (mixed).
Think first. For each question, ask: who decides, and what do they look at?
Country A. What: shops and makers sell the styles and sizes that families buy, watching prices and sales. How: each maker chooses its own machines and workers, to keep costs low. For whom: families who can pay the price.
Country B. What: the planning office sets a number of uniforms for each size, from last year's figures. How: it tells a state factory which machines and workers to use. For whom: uniforms are given out through schools, often at a low fixed price, while they last.
Country C. What and how: private makers decide, as in Country A. For whom: mostly families who can pay, but the government gives free uniforms to families with low incomes.
Check. In each country, all three questions have an answer, and the answer always names who decides. ✓ Country C is the most common kind in the real world.
Three traps
Markets need a government. Someone must protect property, enforce contracts, keep money stable and judge disputes. Without these, people cannot safely buy and sell. "Market economy" means that prices answer most of the three questions, not that the government does nothing.
Each system can be unfair in its own way. Markets can leave poor families with very little. Planned economies had their own unfairness: shortages meant that people with time to queue, or with the right connections, got the scarce goods. Judge a system by what it actually delivers, not by what it promises.
"Mixed" does not mean an even split. It means that a country decides good by good. One country may leave nearly all goods to markets but run its own housing, as Singapore does. Another may leave far fewer goods to markets. Describe the mix by naming the goods.
Work each one on paper first. Open a hint only when you are stuck.
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For each decision, say whether it is made by the market or by a plan. (a) A farmer in Barbados switches from growing sweet potatoes to growing peppers, because peppers now sell for more. (b) A government office tells a factory to make 5 000 tractors next year. (c) A café in Chennai adds a new dish, because customers keep asking for it.
Hint 1
Ask who made the decision, and what they were looking at.
Hint 2
A decision made by an owner after seeing prices or customers is a market decision. A decision ordered by a central office is a plan.
Full answer
(a) Market: the farmer acted on a price signal and the hope of more profit. (b) Plan: a central office set the quantity, not buyers or prices. (c) Market: the café owner acted on what buyers wanted. Check: in (a) and (c), nobody outside the business gave an order. ✓
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In an invented town, mangoes sell for $3.00 a kilogram and cost growers $2.40 a kilogram to produce. A storm destroys half the crop in a nearby region, and the price rises to $4.20. (a) What is the grower's profit per kilogram before and after? (b) Describe what growers and buyers are likely to do. (c) Which of the three jobs of a price does each reaction show?
Hint 1
Profit per kilogram is the price minus the cost.
Hint 2
Think of growers elsewhere who still have mangoes, and of buyers who could choose another fruit.
Full answer
(a) Before: a kilogram. After: , three times as much. (b) Growers in other regions send more mangoes to this town, and some farmers plant more trees. Some buyers buy fewer mangoes or switch to other fruit. (c) The price is a signal (mangoes are scarcer), a reward (growers earn more for supplying them), and a way of sharing out (the mangoes go to buyers who will pay $4.20). Check: . ✓
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Use the bread model from this lecture. The bread people want rises from 100 to 130 thousand loaves a week in week 5. The planners review the plan every 10 weeks, and output changes 2 weeks after a review. In which week does output catch up? How much bread is short in total?
Hint 1
Reviews happen in weeks 10, 20, 30, and so on. Which is the first review in or after week 5?
Hint 2
The first review is in week 10, so output changes in week 12. Count the short weeks from week 5 to week 11.
Full answer
The first review in or after week 5 is in week 10, so output rises to 130 thousand in week 12. Weeks 5 to 11 are short: that is 7 weeks. Each week is short by thousand loaves, so the total is thousand loaves. Check: this lies between the 4-week plan (150) and the 13-week plan (300) in the table. ✓ The market caught up in week 8, with only 60 thousand short, and those short weeks showed up as a higher price, not queues.
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A stretch. An invented country runs a plan. Its planners notice that warm coats are piling up unsold in the south, while shoes have run out in the north. Prices are fixed by the plan. (a) Explain what would happen to the prices of coats and shoes in a market, and how producers would respond. (b) Give two reasons why the planners may be slow to fix the problem. (c) The government decides to let factories sell anything they make above their target at any price. Using the China case, predict what will happen to shoe production, and name one thing that could stop the effect from lasting.
Hint 1
In a market, a pile of unsold goods and an empty shelf both change prices. Which way?
Hint 2
For (b), use the two problems of a plan: information and incentives. For (c), the China case kept the quota and freed the extra.
Full answer
(a) In a market, sellers of coats in the south would cut prices to clear their stock, so coat makers would earn less and make fewer. Shoe prices in the north would rise, so shoe makers would earn more and make more, and traders would move shoes north. Resources would move from coats to shoes. (b) Information: the news must travel to the planning office and wait for the next review. Incentives: a coat factory that has met its target has no reason to stop making coats, and a shoe factory gains nothing by making more than its target. (c) Shoe factories can now earn more by making more than the target, so production should rise, as China's grain output did when farmers could keep the extra. It might not last if the extra gain is one-time, if factories cannot get more leather or machines because those are still planned, or if the government changes the rule again. Check: each answer uses a price, a reward, or the information problem. ✓
Every economy faces the same scarcity and the same three questions. What differs is who answers them, and what they look at when they do. A market listens to prices, so it reacts fast and uses information that no single office could collect. But it hears only those with money, and it makes too little of things that are hard to sell. A plan can aim at a chosen goal and share goods by a rule. But it struggles to know what millions of people want, and to reward those who provide it.
So the real debate in almost every country is not between two pure systems. It is about where to draw the line, good by good: housing, health care, buses, electricity, schools. The next lectures look closely at how markets work, through demand and supply. Later lectures ask when markets fail, and when governments fail too.
- Every economy must answer three questions: what to produce, how to produce it, and for whom to produce it.
- In a market economy, prices act as signals, profit rewards those who respond, and price shares out scarce goods to those willing and able to pay.
- In a planned economy, a central office decides what to produce, which lets it aim at chosen goals but creates problems of information and incentives.
- When prices are fixed and a good is short, the shortage shows up as queues and empty shelves instead of a higher price.
- Almost every real economy is mixed, and countries differ in which goods they leave to markets and which the government provides.