IB Economics rewards using economic concepts as tools to analyse real situations, not reciting them — and the most reliable marks come from fully labelled diagrams (axes, curves, equilibrium points, shaded areas), which are required in almost every answer. Sustain evaluation throughout your essays and commit to a judgement, ground Paper 2 answers in the case-study data, and write your three Internal Assessment commentaries around current news with a diagram and genuine evaluation in each.
IB Economics rewards students who can think with economic concepts rather than just recall them. The subject content — supply and demand, market failure, macroeconomic models, development economics — is the toolkit. What the exam tests is whether you can use those tools to analyse specific economic situations, construct arguments with evidence, and evaluate policy trade-offs.
The most important distinction: every answer should combine a diagram (correctly drawn and labelled) with economic reasoning applied to the specific context in the question. Generic theory without context scores poorly; context-specific analysis with relevant diagrams scores well.
Microeconomics: markets, failure, and intervention
Demand and supply: Law of demand (price ↑ → quantity demanded ↓, ceteris paribus) and law of supply (price ↑ → quantity supplied ↑). Demand shifters: income, prices of substitutes/complements, tastes, expectations, population. Supply shifters: input costs, technology, number of sellers, expectations, natural events.
Elasticities: Price elasticity of demand (PED) = %ΔQd / %ΔP. Elastic (|PED| > 1): revenue falls when price rises. Inelastic (|PED| < 1): revenue rises when price rises. Income elasticity of demand (YED) = %ΔQd / %ΔY: positive for normal goods, negative for inferior goods, >1 for luxury goods. Cross-price elasticity of demand (XED): positive for substitutes, negative for complements.
Market failure: Negative externalities: private costs < social costs → overproduction (production is where MSC = MSB, not where MPC = MPB — market produces where supply = demand, missing the social optimum). Diagram: show the divergence between MPC and MSC (or MPB and MSB), the market equilibrium, the socially optimal output, and the deadweight welfare loss triangle.
Government interventions: Indirect taxes: ad valorem (percentage of price — parallel shift in supply curve) vs specific (per unit — parallel shift). Subsidies: shift supply right, reduce price, increase quantity. Price ceilings (below equilibrium → shortage, reduces producer surplus, may create black markets). Price floors (above equilibrium → surplus — example: minimum wage debates).
Market structures (HL): Perfect competition (many sellers, identical products, free entry/exit, price takers → normal profit in long run). Monopoly (one seller, barriers to entry, price maker, sets MR = MC, higher price and lower output than competitive market → deadweight loss). Monopolistic competition (many sellers, differentiated products, some price-making power, normal profit in long run). Oligopoly (few large sellers, interdependence, kinked demand curve model, game theory, collusion).
Use the Cornell Notes Tool for each market structure: main column = diagram, cue column = key features (number of sellers, product type, barriers to entry, profit type), summary = welfare analysis and implications.
Macroeconomics: the AD/AS framework
Aggregate Demand (AD) components: C + I + G + (X − M). AD curve slopes downward (wealth effect, interest rate effect, international trade effect). AD shifts with: fiscal policy (G and T changes), monetary policy (interest rate and money supply), consumer/business confidence.
Aggregate Supply (AS): Short-run AS (SRAS) slopes upward — firms produce more as price level rises in short run. Long-run AS (LRAS) is vertical at potential output (Yp) — in long run, output is determined by productive capacity, not the price level. LRAS shifts with: changes in quantity or quality of factors of production, improvements in technology, institutional improvements.
Macroeconomic equilibrium: Where AD intersects SRAS (short-run) or LRAS (long-run). Demand-pull inflation: AD shifts right, price level rises. Cost-push inflation: SRAS shifts left, price level rises. Deflationary gap: equilibrium below Yp (recession). Inflationary gap: equilibrium above Yp (short-run, self-correcting in long run via wage inflation).
Policy tools: Fiscal policy (government spending and taxation — expansionary: increase G, cut T; contractionary: cut G, increase T). Monetary policy (central bank interest rate — expansionary: lower rates to stimulate investment and consumption; contractionary: raise rates to reduce inflation). Evaluate trade-offs: expansionary policy reduces unemployment but may increase inflation; contractionary policy reduces inflation but may increase unemployment (Phillips curve relationship).
Development economics
Measuring development: GDP per capita (income measure, ignores distribution); Human Development Index (HDI = income + health + education); Gini coefficient (income inequality); Multidimensional Poverty Index. The gap between measures reveals different aspects of development — a country can have rising GDP per capita with worsening inequality (rising Gini coefficient).
Barriers to development: Poverty cycle (low income → low savings → low investment → low growth → low income), lack of infrastructure, weak institutions and governance, brain drain, geography (landlocked, disease burden, natural disaster risk), terms of trade deterioration for commodity exporters.
Development strategies: Import substitution (protect domestic industries from foreign competition — Argentina, Brazil in mid-20th century — criticism: inefficiency, retaliation), export-led growth (invest in internationally competitive export sectors — East Asian tigers), microfinance (Grameen Bank model — small loans to rural poor, especially women), conditional cash transfers (Brazil's Bolsa Família — cash to poor families conditional on school attendance and health checks).
The Internal Assessment: commentary technique
The 800-word limit is strict — you must be precise and analytical rather than descriptive. For each commentary:
Article selection: Choose an article that illustrates a specific economic concept that you can analyse in depth within 800 words. Avoid articles about multiple economic events — you will lack space to analyse any one of them well.
Diagram: Draw it clearly, label every element (axes, curves, equilibrium points, shifts, areas), and reference it explicitly in your text ("As shown in Figure 1, the negative externality creates a divergence between MPC and MSC...").
Evaluation section: This is where most marks are earned or lost. Evaluate: will the policy achieve its stated aims? What are the trade-offs? What are the limitations of the economic model being used? Are there long-run vs short-run differences? What are the distributional effects?
The Spaced Repetition Flashcard Tool is effective for learning all required diagram types — one card per diagram with a description of all required labels. Build a diagram library and redraw each from memory regularly. The Pomodoro Timer helps for timed essay practice under Paper 1 conditions.
Topics
Frequently asked questions
What are the four units in IB Economics?
IB Economics is organised into four units. Unit 1 — Introduction to Economics: scarcity, choice, opportunity cost, the economic problem, production possibility curves, types of economic systems. Unit 2 — Microeconomics: demand and supply, price elasticity and income elasticity, market failure (externalities, public goods, imperfect information, merit and demerit goods), government intervention (taxes, subsidies, price controls, regulation), market structures (perfect competition, monopoly, monopolistic competition, oligopoly — HL). Unit 3 — Macroeconomics: national income accounting (GDP), AD/AS model, economic growth, unemployment, inflation, fiscal and monetary policy, international trade and balance of payments, exchange rates, terms of trade. Unit 4 — Development Economics: indicators of development, barriers to development, international aid, trade and development strategies, sustainability. HL students study additional topics in each unit, especially mathematical extensions and market structures.
How important are diagrams in IB Economics and how should I use them?
Diagrams are essential in IB Economics and are explicitly required in almost every exam answer. A well-drawn, fully labelled diagram can earn up to 4 marks in a single question and significantly strengthens essay arguments. Every diagram must have: labelled axes (with specific units or at least 'price' and 'quantity'), labelled curves (S, D, MPC, MPB, etc.), labelled equilibrium points (with P₁, Q₁, P₂, Q₂ notation), and shading or annotations for areas of consumer surplus, producer surplus, welfare loss (deadweight loss), externality areas, or government revenue as appropriate. The most common diagram error is drawing the correct diagram but failing to label key elements — this consistently costs marks. Practice drawing each diagram from memory without referring to notes, with all labels, until it takes less than two minutes.
How do I write an evaluative conclusion for IB Economics essays?
IB Economics essays at HL (Section C, Paper 1) require sustained evaluation throughout the essay and a strong evaluative conclusion. Evaluation means: considering the significance of arguments (not just listing factors but weighing them — 'the income effect of the tax may be less significant in markets for luxury goods where elasticity is high'); considering context-dependence (policies that work in high-income countries may not work in developing economies with large informal sectors); identifying trade-offs and conflicting objectives (expansionary fiscal policy may reduce unemployment but increase inflation); considering the limitations of economic models (the AS/AD model assumes price flexibility and full employment tendencies that may not hold). The conclusion must commit to a judgement: which factor is most significant? Under what conditions does the policy work? Avoid 'it depends on many factors' as a conclusion — this earns no marks. State what it depends on and why.
What is the IB Economics Internal Assessment?
The IB Economics Internal Assessment consists of three commentaries (SL) or three commentaries (HL), each approximately 800 words, based on current news articles. Each commentary must: introduce the economic concept illustrated by the article; explain the economics using at least one diagram; evaluate the implications, limitations, or significance of the economic event. Commentaries must cover different units (one each from microeconomics, macroeconomics, and development economics is typical). The most common failing is insufficient evaluation — students describe what the diagram shows and summarise the article, but do not critically evaluate whether the policy will achieve its aims, what the trade-offs are, or what the long-run effects might be. Build IA commentary skills by reading economic news (Financial Times, The Economist, BBC Business) regularly and practising brief economic analysis of news items.
How do I approach the Paper 2 data response questions in IB Economics?
IB Economics Paper 2 presents a case study with data (statistics, graphs, tables) and asks a series of structured questions. Structure of typical responses: Part (a) — define the concept (2 marks, always a definition question); Part (b) — explain using a diagram (4 marks — diagram + explanation); Part (c) — analyse or evaluate using data from the case study and economic theory (8 marks — requires developed argument with evidence). For part (c), the most effective structure is: state your argument → use specific data from the case study to support it → apply economic theory to explain the data → evaluate the implications or limitations. Always reference the data in the case study explicitly, quoting figures where possible — this is the application skill the question is testing.
Build your IB Diploma study system
Use the Cornell Notes Tool for Internal Assessment planning, the Spaced Repetition Flashcard Tool to retain content across HL subjects, and the Active Recall course to develop the retrieval practice habits the IB rewards.
More on IB Diploma Study Guides