The nature of economics and positive and normative statements

Economics as a social science

Economics studies human behaviour, so it is a social science. Unlike a chemist, an economist cannot normally run a controlled experiment: you cannot rerun a country's economy with interest rates 1% higher and everything else identical. People also react to policies, change their minds and are influenced by each other.

So economists rely on observing real data, comparing countries or time periods, and building models.

Models, assumptions and ceteris paribus

A model is a simplified representation of reality used to explain and predict. It rests on simplifying assumptions, for example that consumers act rationally or that firms aim to maximise profit.

The key tool is ceteris paribus, Latin for 'other things being equal'. When we say 'a rise in price reduces quantity demanded', we assume income, tastes and the prices of other goods stay the same. Holding other factors constant lets us isolate the effect of one variable.

Evaluation point you can use in any essay: a model's prediction is only as good as its assumptions. In reality other things are rarely equal, so the outcome may differ from the prediction.

Positive and normative statements

• A positive statement is a statement of fact or a testable claim. It can be checked against evidence and shown to be right or wrong. Example: 'A 10% rise in the price of cigarettes reduced sales by 4%.' (It may be false, but it can be tested.)
• A normative statement contains a value judgement: an opinion about what ought to happen. It cannot be proved true or false by evidence. Clue words: should, ought, fair, better, too high, unacceptable. Example: 'The government should tax sugary drinks.'

Value judgements matter because policy choices are normative. Two economists can agree on the positive facts (a tax will raise prices and reduce consumption) and still disagree on whether the tax is fair to low-income households.

Exam technique

In multiple choice, look for the testable claim. A statement with numbers is not automatically positive if it also says what 'should' happen. A positive statement can be false: 'Unemployment fell to 0% last year' is positive even if wrong.

In a short-answer 'explain the difference' question, define each term (1 mark each) and apply each to the context given (1 mark each).

Worked example

Classify: (i) 'Raising the minimum wage will reduce employment among young workers.' (ii) 'The minimum wage is too low to live on and should be raised.'

1. (i) is a claim about cause and effect that can be tested with data on employment, so it is positive.
2. (ii) contains 'too low' and 'should', which are value judgements, so it is normative.

Answer: (i) positive; (ii) normative.

Check yourself

1. Which statement is positive?
   • Fuel duty is unfair on rural drivers
   • The government ought to cut fuel duty
   • Petrol is far too expensive
   • An increase in fuel duty will reduce petrol consumption
   Show answer

   An increase in fuel duty will reduce petrol consumption. It is a cause and effect claim that can be tested against evidence.

2. Which statement is normative?
   • In 2025 the price of rice rose by 8%
   • Healthcare should be free for everyone at the point of use
   • Higher income usually leads to more spending on holidays
   • A subsidy lowers the price paid by consumers
   Show answer

   Healthcare should be free for everyone at the point of use. 'Should' expresses a value judgement.

3. What does 'ceteris paribus' mean in an economic model?
   • The market is in equilibrium
   • Consumers are always rational
   • Prices are fixed by the government
   • All other factors are held constant
   Show answer

   All other factors are held constant. It lets the economist isolate the effect of one variable.

4. Why is economics described as a social science?
   • It studies human behaviour, so controlled experiments are rarely possible
   • It uses no numbers or data
   • Its theories can always be tested in a laboratory
   • It is concerned only with government policy
   Show answer

   It studies human behaviour, so controlled experiments are rarely possible. People's choices are its subject matter, and economies cannot be rerun under controlled conditions.

5. 'Inflation in the country was 50% last year' (when in fact it was 3%). This statement is
   • normative, because it is incorrect
   • normative, because it uses a percentage
   • positive, because it can be tested and shown to be false
   • neither positive nor normative
   Show answer

   positive, because it can be tested and shown to be false. Positive statements can be wrong; what matters is that they can be tested.

6. Explain one limitation of using economic models to make predictions.
   Show answer

   Models rely on simplifying assumptions such as ceteris paribus, but in reality other factors change at the same time, so the actual outcome may differ from the model's prediction.. Name the assumption (ceteris paribus or rationality) and explain why reality may not match it.

7. Explain why two economists who agree on the facts may still recommend different policies.
   Show answer

   Policy choices involve value judgements, which are normative. Economists may agree on the positive effects of a policy but weigh them differently, for example placing different importance on fairness or efficiency.. Positive analysis tells you what happens; deciding whether it is good is normative.

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Sources

• Pearson Edexcel International Advanced Subsidiary/Advanced Level in Economics specification (2018)

Last updated 8 November 2026. Spotted a mistake? Tell us.