A market can be perfectly efficient and still leave some people with almost nothing. Efficiency asks whether resources went where they were most valued. It never asks whether the result was fair. That gap is why economists study equity separately — and why almost every government interferes with the outcome the market produces.
📘 What you need to know
In a free market the price mechanism allocates resources with no government involvement.
Capitalism means the factors of production are privately owned, and workers are paid wages by those owners.
Equity means fairness. It is not the same as equality, which means sameness.
Income is a flow earned over time (wages, rent, interest, profit). Wealth is a stock of assets you own.
Free markets create unequal income because people own different amounts of the factors of production and have different earning capacity.
Inequality tends to compound: wealth generates income, which buys more wealth.
Governments respond with progressive taxes, transfer payments, minimum wages, education and labour market regulation.
Equity is not equality
Equality would mean everyone receives the same. Almost nobody argues for that, because effort, training, risk and hours worked genuinely differ. Equity is a softer and more useful idea: that the gap should be justifiable, and that nobody should be locked out of a decent life by where they happened to be born.
Two words that get mixed upEquality = everyone gets the same Equity = the differences are fair and opportunity is open to all
Because “fair” is a value judgement, questions about equity are normative. That is not a weakness in your answer — say so directly, and you have already earned an evaluation mark.
Income and wealth: two different things
Income (a flow)
What a household receives over a period of time. It comes from four sources, one for each factor of production:
Wages for labour
Rent for land
Interest for capital lent out
Profit for enterprise
Wealth (a stock)
What a household owns at a moment in time: property, shares, savings, a business, land.
Wealth is normally spread far more unequally than income, because it accumulates over a lifetime and can be passed on to the next generation.
Using the circular flow to see where inequality comes from
The circular flow model shows households supplying factors of production to firms, and firms paying households for them. Follow the money round and you can see exactly which arrow produces the inequality.
Everyone appears on the diagram, but not on equal terms. Whether you receive one payment or four depends on what you own before the flow even starts.
Five reasons the gap appears
🧩 Where free-market inequality comes from
Unequal ownership of factors. Everybody has labour to sell. Only some people also own land, capital or a business, and those assets pay rent, interest and profit on top of a wage.
Differences in earning capacity. Skills, qualifications, experience and health are not spread evenly, and higher-skilled jobs command higher wages.
Inheritance. Income and wealth pass from one generation to the next, so an advantage that began generations ago is still being handed on today.
The power to save. Only households with income above their needs can save. Savings buy assets, assets pay income, and that income buys more assets — so wealth compounds.
Unequal opportunity. Better-off families can buy better education and healthcare, which raises their children’s future earning capacity. Today’s income gap becomes tomorrow’s skills gap.
🤔 Why the market cannot correct this by itself
The price mechanism responds to purchasing power, not to need. A market will happily build luxury flats while people sleep outside, because the demand backed by money is in the flats. Nothing in the model pushes the outcome towards fairness, so if society wants a fairer result, it has to be arranged deliberately.
Picturing inequality: the Lorenz curve
Rank households from poorest to richest and plot the cumulative share of income they receive. If income were shared perfectly equally the plot would be a straight diagonal. In reality it sags below, and the size of the sag is the size of the inequality.
Read one point off it: at 60% along the bottom the curve is at 30%. So the poorest three fifths of households share less than a third of all income between them.
What governments do about it
Policy
How it reduces inequality
Possible drawback
Progressive taxation
Higher earners pay a larger share of income; the revenue funds services for lower-income groups
Very high rates may weaken the incentive to work, or push people to avoid tax
Transfer payments
Pensions, unemployment benefit and child support raise the incomes of those with least
Costly, and if set badly can reduce the incentive to take low-paid work
Minimum wage
Sets a floor under pay, so the lowest-paid workers earn more
If set well above the market wage, firms may cut hours or jobs
Education and training
Raises human capital, so people can move into higher-paying work
Works only in the long run, and needs sustained funding
Labour market regulation
Safe conditions, overtime pay, anti-discrimination rules and union rights protect weaker workers
Raises costs for firms, which can reduce hiring
Wealth and inheritance taxes
Slows the passing of large advantages between generations
Wealth is mobile and hard to value, so avoidance is common
The trade-off to name in an essay: policies that make the distribution fairer can weaken the incentives that make the economy efficient. How far a country goes is a political choice, not something economics can settle.
Worked examples
WORKED EXAMPLE 1
Households are split into fifths. Their shares of national income are: poorest 5%, second 10%, third 15%, fourth 22%, richest 48%. (a) What share do the poorest 60% receive? (b) How many times more income does the richest fifth receive than the poorest fifth? [3]
(a) Add the first three fifths5 + 10 + 15 = 30The poorest 60% receive 30% of income(b) Compare top and bottom fifth48 ÷ 5 = 9.6The richest fifth receives 9.6 times as muchCheck the shares add to 100 before you start. Here 5 + 10 + 15 + 22 + 48 = 100.
WORKED EXAMPLE 2
Explain two reasons why a free market tends to produce an unequal distribution of income. [4]
Reason 1: unequal ownership of factors of production
In a free market, income is a payment for what you own.
Everyone can sell labour, but only some own land, capital or a business, so those households earn rent, interest and profit as well as a wage.
Reason 2: differences in earning capacity
Skills and qualifications are not spread evenly, and higher-skilled work commands higher wages.
Households that could afford more education earn more, and can then afford more education for their children.
Both reasons widen the gap over time rather than closing itTwo clear reasons, each developed one step. Do not list six reasons with no explanation.
💡 Exam tip
Separate income and wealth in the first line of any answer. They behave differently and the distinction earns marks.
Use the circular flow to structure an explanation: who supplies what, and who is paid for it.
Say plainly that equity is a normative issue. That is analysis, not a get-out.
When a question asks about policy, name the policy, explain the mechanism, then give one drawback.
Remember efficiency and equity are different tests. A market can pass one and fail the other.
Quantify when data is given. One calculation from a Lorenz curve or a quintile table is worth more than a paragraph of description.
⚠ Common mix-up
Treating equity and equality as the same word. They are different ideas and examiners test the difference.
Confusing income with wealth. Income is a flow per period; wealth is a stock at a point in time.
Saying free markets are “inefficient” because they are unfair. They can be perfectly efficient and still unfair.
Reading the Lorenz curve backwards. Households are on the horizontal axis, ranked poorest first.
Claiming redistribution has no cost. Always mention the incentive effects.
Listing policies without a mechanism. “Progressive tax reduces inequality” needs the step that explains how.
Up next: Measuring Inequality: Lorenz Curves and the Gini Coefficient — turning the sag in that curve into a single number you can compare between countries.
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