SECO202: Macroeconomics 2 Exam Prep

SECO202: Macroeconomics 2 typically builds on core macroeconomic foundations by adding deeper treatment of national income accounting, aggregate demand and supply, inflation and unemployment dynamics, and open-economy macroeconomics. Exam questions often test your ability to move between models (with diagrams and equations) and policy interpretation for real economies—including South Africa’s historical and structural context. This study guide is designed to help you prepare in a structured way for typical university/college exam formats, with emphasis on the kind of reasoning and derivations that get full marks.

SECO202 at South African Institutions: What Exams Commonly Test

Macroeconomics 2 exams in South Africa are frequently assessed through a mix of short theory questions, model-based derivations, graph interpretation, and application to economic data. While course syllabi differ between universities, the learning outcomes tend to cluster around similar macro “modules.” Your goal is to be able to (1) recall the right concepts, (2) derive key relationships quickly and accurately, and (3) explain policy implications in words tied to the South African context.

Core exam skill set: from definitions to reasoning

A high-scoring answer usually has three layers:

1. Conceptual correctness
   • You define the term precisely (e.g., real vs nominal variables, output gap, natural rate, balance of payments components, fiscal multipliers).
2. Model mechanics
   • You show the relationship using equations or correct diagrams: e.g., IS–LM logic, AD/AS shifts, Phillips curve interpretation, money market, exchange rate effects.
3. Interpretation and policy
   • You connect the model to a policy decision (e.g., tax changes, interest-rate adjustments, exchange rate interventions, inflation targeting constraints), and you mention plausible outcomes and risks.

South African exams often reward students who can:

• justify why a variable moves (e.g., “higher inflation expectations shift short-run AS left/right”),
• link multiple markets (goods, money, labour), and
• interpret policy in conditions that resemble South Africa (high unemployment, inflation pressures, exchange-rate pass-through, fiscal constraints).

Typical question types you should practice

Below are the most common SECO202-style question formats and what graders look for.

1) Short theory (4–8 marks each)

These require crisp definitions and short explanations.

Examples of what might be tested:

• Define aggregate demand and list its components.
• Distinguish GDP at current prices vs constant prices.
• Explain the meaning of inflation targeting and its assumptions.
• Describe the difference between nominal and real interest rates (and the Fisher relationship).

Grading emphasis: a complete definition, plus at least one correct implication.

2) Diagram-based questions (10–20 marks)

Often you must draw and explain:

• AD/AS:
  • shift of AD (fiscal policy, monetary policy, exchange rate effects),
  • shift of AS (cost-push shocks, demand-pull, supply constraints).
• Phillips curve:
  • short-run vs long-run,
  • role of expectations.
• Money market / interest rate:
  • how changes in money supply affect interest rates and investment.

Grading emphasis: correct axes, correct direction of shifts/movements, and a coherent explanation.

3) Calculations and model substitution (10–25 marks)

Some papers include numeracy: multipliers, output gaps, inflation equations, or balance-of-payments identities.

Common calculations:

• Compute output in a Keynesian cross model.
• Apply the Fisher equation: (i \approx r + \pi) (or exact form (1+i=(1+r)(1+\pi)) depending on lecturer conventions).
• Use a simplified money market: (M/P = L(Y,i)) style logic.
• Use national income identities to derive expenditure or income components.

Grading emphasis: show working; substitute carefully; units and signs must be consistent.

4) Open-economy policy reasoning (15–25 marks)

Questions often ask: “How would the economy respond under X policy in a small open economy?” with exchange rates and external balances.

Expect concepts like:

• trade balance / current account,
• capital flows and interest differentials,
• exchange rate depreciation/appreciation effects,
• pass-through from exchange rates to inflation.

Grading emphasis: both direct and indirect channels.

South African contextual hooks (how to earn marks with relevance)

Even if the lecturer doesn’t explicitly require South Africa, exam setters may use South African examples in wording. You score higher when you acknowledge plausible constraints:

• Fiscal constraints:
  • higher debt servicing costs can limit stimulus.
• Inflation persistence:
  • administered prices, exchange-rate pass-through, and wage bargaining can create sticky inflation.
• Labour market rigidities:
  • unemployment dynamics may not match a simple “flexible wages” assumption.
• Energy and input shocks:
  • supply-side shocks can shift short-run aggregate supply.

This guide will weave South African examples in a way that stays consistent with core macro models.

Cluster 1: University of Johannesburg (UJ) — SECO202 Macro Module Focus & Exam Strategy

This cluster is designed around the way many South African universities structure Macro 2 content: macroeconomic models, stabilisation policy, inflation-unemployment trade-offs, and open-economy transmission. Treat it as a “single institution” study path: one continuous revision flow, focusing on the specific course themes that typically appear in the SECO202 macro exams (even if exact chapter names vary).

UJ-style focus areas: what to prioritise for marks

Most Macro 2 exams test whether you can connect core relationships:

1. Aggregate demand (AD) and aggregate supply (AS
2. Stabilisation policy: fiscal vs monetary
3. Inflation dynamics and the Phillips curve
4. Open economy: exchange rates, capital flows, and external balance
5. Output gaps and policy trade-offs under uncertainty

Even if your UJ SECO202 notes label these differently, the exam patterns remain similar: you’re graded for correct logic and interpretive clarity.

A) Aggregate Demand: make your components automatic

A standard AD framework in undergraduate Macro 2 uses:

• Consumption (C) depending on disposable income and perhaps an MPC (marginal propensity to consume),
• Investment (I) depending on interest rates and expected profitability,
• Government spending (G),
• Net exports (NX = X – M) depending on relative prices, exchange rates, and income.

You should be able to answer quickly:

• What increases AD?
• What decreases AD?
• How fiscal changes affect equilibrium output in a Keynesian model?
• How monetary policy affects interest rates and therefore investment?

A typical reasoning chain:

• An increase in (G) raises AD directly.
• Higher AD raises output (Y).
• Higher (Y) increases income and consumption (C).
• That feeds back into AD via the multiplier.

Your exam advantage is to state the chain clearly and, where required, show the equations.

B) Aggregate Supply: differentiate short-run vs long-run

Macro 2 typically emphasizes:

• Short-run aggregate supply (SRAS): influenced by wages/prices and sticky aspects (expectations, contracts, input costs).
• Long-run aggregate supply (LRAS): classical output determined by real factors (technology, labour, capital), often associated with a “natural output.”

Key exam phrase you should master:

• In the long run, monetary and demand management cannot permanently raise output beyond potential; they may affect the price level.

That doesn’t mean policy is pointless—rather, it affects inflation and transitional dynamics.

C) Inflation-Unemployment: Phillips curve with expectations

In more advanced coverage, Macro 2 uses a Phillips curve with expectations:

• Short-run Phillips curve: unemployment and inflation are negatively related, but
• Long-run: unemployment returns to its “natural” level regardless of inflation, assuming expectations adjust.

A policy question might sound like:

• “If policymakers want to reduce unemployment, what happens to inflation in the short run and what occurs in the long run?”

Your answer must include:

1. Short-run: unemployment falls (output rises) with higher inflation.
2. Long-run: as expectations adjust, unemployment returns to natural rate; inflation remains higher if policy persists.

This logic often appears in diagram questions.

UJ-specific exam strategy: diagram discipline and policy language

A common reason students lose marks is not conceptual ignorance, but diagram imprecision. Use this checklist in every diagram-based question:

1. Label axes correctly:
   • For AD/AS: usually price level on vertical axis, output on horizontal axis.
   • For Phillips curve: inflation (or wage inflation) on vertical axis, unemployment on horizontal axis.
2. Identify which curve shifts:
   • Fiscal policy usually shifts AD (left/right).
   • Cost-push shocks shift SRAS (left/upward effects).
3. State the effect on both price level and output:
   • In short-run: output can rise while prices rise.
   • In long-run: output returns to potential but price level shifts.
4. Use consistent arrows:
   • Keep arrow directions consistent with the reasoning (no “contradiction arrows”).

Open economy: channel-based answers (this is where many marks live)

Many Macro 2 exams ask about small open economy logic. You must explain:

• Exchange rate depreciation:

  • makes exports cheaper, imports more expensive → improves net exports (NX rises),
  • but can raise inflation via imported input costs and pass-through,
  • and can affect expectations and monetary policy credibility.

• Interest rate changes:

  • higher domestic interest rates attract capital → appreciation (depending on capital mobility assumptions),
  • appreciation reduces net exports → dampens AD.

A high-mark open economy answer:

1. starts with a policy action,
2. identifies the transmission channel (exchange rate, capital flows, trade),
3. concludes with output and price effects.

Example: depreciation shock with inflation pass-through

Suppose the exchange rate depreciates. In many simplified models:

• (NX) improves → AD increases → output rises in the short run.
• But import prices rise → SRAS shifts left (higher costs) → inflation rises.
  Your final conclusion: short-run output may rise but inflation increases; policymakers face a trade-off.

South Africa tie-in: policy trade-offs under constraints

South Africa has features that can strengthen “sticky inflation” stories:

• Wage bargaining and inflation expectations can maintain inflation persistence.
• Energy costs and administered price adjustments can create cost pressures (cost-push).
• Exchange rate movements can feed into import prices.

In an exam, you don’t need exact current-year values unless explicitly asked. But you should describe how these features affect:

• the speed of adjustment from short-run to long-run outcomes,
• the effectiveness of stabilisation policy,
• and the risks of policy overreach.

Practice-oriented mini-exam tasks (UJ cluster)

These are “practice templates” that mirror how exam answers should look.

Task 1: Fiscal expansion in AD/AS

Answer structure (10 marks typical):

1. Define fiscal expansion (increase (G)).
2. Explain AD shift right.
3. Discuss short-run equilibrium: higher output, higher price level.
4. Explain transition: higher output may increase wages/costs; SRAS shifts.
5. Long-run: output returns to potential; price level ends up higher than initially.
6. Mention crowding-out if interest rates rise (if your class includes IS–LM logic).

Task 2: Monetary tightening and unemployment

Answer structure:

1. Tightening reduces money supply growth / increases interest rate.
2. Lower interest rate reduces investment (and/or lowers AD).
3. AD shifts left → lower output in short run → unemployment rises.
4. Inflation falls over time as demand cools.
5. In long run: unemployment returns to natural rate.

Task 3: Open economy exchange rate shock

Answer structure:

1. Identify shock (depreciation).
2. Trade channel: NX rises.
3. Inflation channel: pass-through raises prices → SRAS left.
4. Policy response: central bank may tighten to stabilise inflation, changing interest rates and exchange rates.
5. Net effect: ambiguous output effect, but likely inflation increase unless policy offsets.

This cluster’s overall message: your marks increase when you describe the transmission channels in a numbered, coherent chain.

Cluster 2: University of Pretoria (UP) — SECO202 Inflation, Unemployment, and Policy Frameworks

This cluster focuses on a very common “Macro 2 heavy” exam area: inflation dynamics, unemployment models, and stabilisation policy under expectations. Many South African macro courses taught at research-intensive universities emphasise theoretical clarity: you should show the logic behind each model assumption, not only the final answer.

UP-style focus areas: what to prioritise for SECO202 Inflation & Labour

Typical exam emphasis includes:

1. Fisher equation and interest rate relationships.
2. Inflation measurement (CPI vs GDP deflator basics).
3. Phillips curve with expectations.
4. Natural rate / NAIRU concepts.
5. Policy regime credibility: why expectations matter.

A) Nominal vs real: quick equation reflexes

You should be able to move instantly between:

• Nominal interest rate (i)
• Real interest rate (r)
• Expected inflation (\pi^e)

Core relationship (common undergraduate form):

• (i \approx r + \pi^e)

If the exam asks for exactness and uses the multiplicative version:

• ((1+i) = (1+r)(1+\pi))

But in many exam settings, approximation is accepted.

How this becomes exam-winning:
If policymakers lower nominal rates while inflation rises, real rates may not actually fall—so demand may not stimulate as much as expected.

That is exactly the kind of “policy misconception” examiners want you to correct.

B) Phillips curve with expectations: what to state explicitly

A classic structure:

• Short-run Phillips curve: inflation depends on unemployment relative to natural unemployment plus expected inflation.
• Long-run: inflation and expectations determine the inflation outcome; unemployment reverts to natural unemployment.

You should use clear language:

• If unemployment is below natural rate, inflation tends to rise.
• If unemployment is above natural rate, inflation tends to fall.

Then tie it to policy:

• Expansionary policy can reduce unemployment temporarily, but if sustained, inflation expectations adjust and the long-run unemployment target cannot shift.

C) The “policy credibility” angle: where marks often come from

Examiners love asking:

• “Why does inflation persist after a disinflation attempt?”
• “Why are expectations important?”

Even if the model doesn’t formally include credibility, you can still argue:

• If agents believe future inflation will remain high, then wage/price setters build those expectations into their decisions.
• That shifts SRAS and keeps inflation elevated even if demand cools.

A strong answer mentions:

• expectations channel,
• contract-wage dynamics,
• imported inflation (in open economy settings),
• and possible supply shocks.

Inflation shocks and output: cost-push vs demand-pull

In AD/AS terms (or in inflation equations), two broad shock types appear:

1. Demand-pull:

   • Higher AD (e.g., fiscal expansion or loose monetary policy).
   • Tends to raise output above potential temporarily, raising inflation.

2. Cost-push:

   • Higher production costs (e.g., energy prices, wage shocks, imported inputs).
   • Tends to raise inflation even if output falls.

A high-mark approach in exams:

• For demand-pull: AD shifts right; SRAS may remain initially but inflation rises and SRAS shifts later.
• For cost-push: SRAS shifts left immediately; output falls and inflation rises at once.

UP exam questions often reward students who can tell these apart because policy responses differ:

• With cost-push, monetary tightening may reduce inflation but could deepen recession.
• With demand-pull, tightening can reduce inflation while avoiding long-run output damage.

South Africa relevance: inflation persistence and labour outcomes

In South Africa, inflation dynamics are often shaped by:

• wage bargaining and labour market bargaining outcomes,
• exchange rate movements affecting imported goods prices,
• administered prices and energy cost changes,
• structural unemployment affecting the “natural rate” concept (or labour market slack).

When writing exam answers, you can mention these factors as plausible contributors to:

• inflation persistence (why inflation expectations move slowly),
• unemployment persistence (why unemployment may not respond quickly to demand stimulus),
• and the asymmetric effects of shocks.

You should avoid making up precise numbers unless the question provides them. Instead, focus on causal direction: “if unemployment remains high due to labour market structure, then expansionary policy may not reduce unemployment permanently.”

Practice problem set (UP cluster): answer frameworks

Problem 1: Explain a government trade-off

Prompt (typical style):

Use a Phillips curve framework to explain the trade-off between inflation and unemployment when policymakers choose an expansionary fiscal policy.

Answer skeleton:

1. Expansionary fiscal → AD increases → unemployment temporarily below natural.
2. With unemployment below natural, inflation rises in the short run.
3. Over time, expectations adjust; SR inflation becomes higher but unemployment returns to natural.
4. Conclusion: short-run trade-off exists; long-run trade-off does not (under standard assumptions).

Add marks by mentioning:

• persistent policy leads to higher inflation expectations,
• if inflation expectations are anchored, inflation outcomes could be more manageable.

Problem 2: Disinflation attempt

Prompt:

Discuss why disinflation may fail if expectations are not credible.

Answer skeleton:

1. Central bank tightens → AD falls → unemployment rises short run → inflation falls initially.
2. If people doubt the long-term intention to keep inflation low, expectations remain high.
3. Wage/price setting maintains inflation; SRAS keeps shifting.
4. Outcome: higher unemployment for longer with limited inflation reduction.

This shows you understand the expectations mechanism.

Problem 3: Cost-push shock interpretation

Prompt:

A rise in energy prices increases firms’ costs. Illustrate and explain the effects on inflation and unemployment.

Answer skeleton:

1. Cost-push → SRAS shifts left (in AD/AS terms).
2. New equilibrium: lower output and higher inflation.
3. Unemployment rises due to lower output.
4. Policy options:
   • Tighten: reduces inflation but increases unemployment,
   • Loosen: reduces unemployment but risks higher inflation persistence.

This is the “policy dilemma” examiners often look for.

Cluster 3: Stellenbosch University (SU) — SECO202 Open-Economy Macro, Exchange Rates, and External Balance

This cluster targets another frequent SECO202 exam theme: open economy macroeconomics—the interplay between domestic output, inflation, interest rates, and exchange rates. Stellenbosch-style content (often seen in economics faculties) may be more model-driven. You should therefore emphasise the structure of identities and the logic of transmission channels.

SU-style focus areas: identities and transmission

Open-economy macro often requires two things:

1. Accounting identities

   • Balance of payments components and relationships (current account, capital/financial account, official reserves).

2. Behavioural relationships

   • How exchange rate affects net exports.
   • How interest rate differentials affect capital flows.
   • How domestic prices respond to exchange rate changes.

A) Core external balance concept: current account and net exports

A simplified view links:

• Current account to net exports:
  • (CA \approx NX) (under certain assumptions that abstracts from factor income).

In a basic macro model:

• Depreciation → exports increase, imports decrease → NX rises → current account improves.

But in reality (and many exam discussions), you should acknowledge:

• J-curve effects: trade balance may deteriorate initially due to contracts and import invoicing delays, then improve later.
• Import cost inflation: depreciation may raise import prices, feeding into inflation and potentially weakening competitiveness later.

B) Capital flows and interest parity logic

Many exam questions use simplified uncovered interest parity intuition:

• If domestic interest rates rise relative to foreign rates, capital inflows occur (for a given exchange rate expectation), tending to appreciate the currency.
• Appreciation reduces net exports, offsetting some of the demand impulse.

You don’t need to write the full UIP equation if not required—but you must mention:

• interest-rate change affects exchange rate,
• exchange rate affects net exports,
• net exports feed back into output.

C) Exchange rate pass-through to inflation: why it matters for policy

A key Macro 2 exam idea:

• Exchange rate depreciation can increase inflation via imported inputs and consumer goods.

This implies:

• If inflation is the policy objective, policymakers may need to counter depreciation with tighter monetary policy.
• But tightening reduces output (and increases unemployment), creating a trade-off.

So “exchange rate movements” are not purely external—they influence domestic inflation dynamics, and that connects directly to Phillips curve logic from Cluster 2.

AD/AS in an open economy: building an integrated narrative

In many exams, you must integrate open economy effects into AD/AS. A coherent narrative:

1. Start with a policy or shock:
   • depreciation, fiscal expansion, global interest rate change, commodity price shock.
2. Explain AD effects:
   • net exports shift AD.
3. Explain AS effects:
   • exchange rate pass-through shifts SRAS.
4. Conclude with equilibrium outcomes:
   • output and inflation in short run,
   • and likely long run return to potential output with different price level.

This integration is a hallmark of strong Macro 2 answers.

SU practice: model-based scenario exercises

Scenario 1: Fiscal expansion with high capital mobility

Prompt:

A government increases spending. In a small open economy with high capital mobility, how would output, interest rates, and the exchange rate respond?

A strong answer sequence:

1. Fiscal expansion increases AD directly.
2. Output rises short run → interest rates may rise (if money market is considered) or if higher output increases money demand.
3. Higher interest rates attract capital → currency appreciates.
4. Appreciation reduces net exports → partially offsets fiscal stimulus.
5. Final: output rises less than in a closed economy; inflation may rise depending on SRAS behaviour.

This tests whether you can combine:

• goods market effects (fiscal → AD),
• financial market/capital flow effects (interest differentials → exchange rate),
• and external balance effects (exchange rate → NX).

Scenario 2: External shock—global recession lowers foreign demand

Prompt:

Global recession reduces demand for the country’s exports. Explain the effects in an open-economy AD/AS framework.

Answer:

1. Lower foreign demand → exports fall → NX falls → AD shifts left.
2. Output decreases short run; unemployment rises.
3. If the currency depreciates in response (depending on the exchange rate regime and capital flows), imported goods become more expensive.
4. That may raise inflation through pass-through even while output falls—possibly creating stagflation-like dynamics.

This scenario links external shocks to both AD and AS.

Scenario 3: Currency depreciation due to risk premium increase

Prompt:

A rise in the global risk premium leads to capital outflows and depreciation. Describe likely short-run macro outcomes.

Answer:

1. Risk premium increase → outflows → depreciation.
2. Depreciation improves NX (AD up) but raises imported costs (AS down).
3. Output effect ambiguous; inflation likely rises because SRAS shifts left.
4. Monetary policy may tighten to contain inflation, reducing output further.

Again, clarity about which curve shifts and why is critical.

South Africa relevance: why external balance and exchange rates are central

South Africa is a compelling case for open-economy macro:

• exchange rate volatility can transmit strongly into inflation,
• external financing conditions can affect currency and interest rates,
• trade competitiveness and commodity-linked exports can be sensitive to global demand.

In exam writing, you can reference these as plausible channels:

• “If imports are a significant share of consumption and intermediate inputs, depreciation raises costs and inflation.”
• “If the economy depends on foreign capital for investment, risk-premium changes affect capital flows and the exchange rate.”

Keep it model-consistent: depreciation affects both AD and AS.

Cluster 4: North-West University (NWU) — SECO202 Data Interpretation, Multipliers, and Exam-Ready Problem Solving

This final cluster is about execution: how to answer calculation-heavy questions, interpret macro data, and avoid common pitfalls (sign errors, wrong direction, missing terms). Many NWU-style applied macro exams emphasize practical reasoning: you must use the models correctly with numbers when they’re provided.

NWU-style focus areas: calculation discipline and interpretation

Your calculation performance usually improves when you focus on four areas:

1. National income identities
2. Keynesian multipliers
3. Inflation/unemployment interpretation
4. Linking results to policy conclusions

A) National income accounting: be precise about components

A typical exam identity:

• (Y = C + I + G + NX)

Where:

• (Y) is output/income,
• (C) consumption depends on disposable income,
• (I) investment depends on interest rates,
• (G) government expenditure,
• (NX) net exports.

In many problems, the question provides:

• MPC (marginal propensity to consume),
• autonomous consumption (C_0),
• tax function (T) (lump-sum or proportional),
• investment (I_0),
• and a trade function (often simplified).

Your task is to solve for equilibrium output (Y^*) in a Keynesian cross or related model.

B) Multipliers: understand rather than memorize

In the simplest Keynesian cross model:

• (C = C_0 + c(Y – T))
• (T) might be lump-sum, so disposable income is (Y-T).
• (I) and (G) are autonomous in the simplest version.

Aggregate expenditure:

• (AE = C + I + G)

Equilibrium:

• (Y = AE)

If you derive carefully, the multiplier emerges as a function of MPC and taxes (depending on tax structure).

A common exam trap:

• Mixing up whether taxes reduce consumption through (T) being lump-sum or proportional.

So your best strategy:

1. Write down the consumption function exactly as given.
2. Substitute into (AE).
3. Set (Y = AE).
4. Solve for (Y) algebraically with working.

C) A complete worked example (template you can reuse)

Assume an exam provides the following simplified Keynesian model:

• (C = 100 + 0.8(Y – 50))
• (I = 40)
• (G = 60)
• (NX = 0) (closed economy simplified)

Step-by-step:

1. Compute consumption:
   [
   C = 100 + 0.8(Y – 50) = 100 + 0.8Y – 40 = 60 + 0.8Y
   ]
2. Total expenditure:
   [
   AE = C + I + G = (60 + 0.8Y) + 40 + 60 = 160 + 0.8Y
   ]
3. Equilibrium (Y = AE):
   [
   Y = 160 + 0.8Y
   ]
4. Solve:
   [
   Y – 0.8Y = 160 \Rightarrow 0.2Y = 160 \Rightarrow Y = 800
   ]

If the exam asks the effect of increasing (G) by a certain amount (say (+10)), you can compute:

• the multiplier is (1/(1-0.8)=5),
• so equilibrium output increases by (5 \times 10 = 50).

This style of derivation is what examiners typically reward: clear substitution and correct algebra.

Important: if the tax structure changes or there is a proportional tax rate (t), the multiplier becomes (1/(1-c(1-t))). Always match the formula to the given tax form.

Interpreting exam questions: “what are they really asking?”

NWU-style exam questions often include multiple parts, and students lose marks by answering the wrong “layer.” For example:

• If a question asks “Explain the impact on inflation and unemployment,” it’s not enough to say “unemployment falls.” You must mention inflation mechanism too.
• If it asks “Describe the effect of depreciation under floating exchange rates,” you must discuss both exchange rate adjustment and macro impacts.

Use this answer checklist:

1. State the shock/policy
2. Identify impacted markets
   • goods market → output
   • money market → interest rates
   • exchange rate → net exports and inflation
   • labour market → unemployment and inflation via expectations/wages
3. Use the correct model tool
   • AD/AS, Phillips curve, Keynesian cross, balance of payments
4. Give the sign and direction
   • up/down for each variable asked
5. Add a short justification
   • one sentence per direction is usually sufficient
6. Conclude policy implication
   • trade-off and uncertainty

Common mistakes (and how to avoid them)

Mistake 1: Wrong sign for net exports

• Depreciation (in many simplified models) increases exports and decreases imports, so (NX) rises.
• Appreciation decreases (NX).

If you consistently flip it, your diagrams and numerical answers will contradict.

Mistake 2: Confusing real and nominal variables

• Inflation affects nominal interest rates; real interest rates drive investment in many models.
• If inflation rises and nominal interest rates don’t adjust, real rates can fall.

Mistake 3: Inconsistent use of “short run” and “long run”

• AD/AS logic: short run equilibrium may show output changes; long run typically returns to potential output with a higher/lower price level.
• Phillips curve: short run unemployment may move; long run returns to natural.

Mistake 4: Algebra errors in multipliers

• Always check by substitution:
  • If you calculate (Y), plug back into the expenditure equation quickly to verify.
  • If your output doesn’t satisfy (Y = AE), you made an error.

Integrated SECO202 Macro 2 Revision Plan (Last 2–3 Weeks)

The following plan is designed to unify the clusters above into a single revision flow, so you don’t treat topics as separate. Each day includes a model skill and a policy interpretation skill.

Week structure (example 10-day sprint)

Day 1: National income identities + Keynesian cross practice

• Solve 2 equilibrium output questions with given (C(Y-T)), (I), (G).
• One question with proportional taxes if provided.

Day 2: Multipliers + fiscal policy diagrams

• Derive multiplier (closed economy).
• Apply to an increase in (G) and compute change in (Y).

Day 3: AD/AS demand shock

• Demand-pull: shift AD, explain output and inflation short run; return to potential in long run.

Day 4: AD/AS supply shock

• Cost-push: SRAS shift, explain stagflation-like dynamics.

Day 5: Fisher equation + nominal/real interest relationships

• Practice conversions and interpret what happens to real rates under inflation changes.

Day 6: Phillips curve expectations

• Short run unemployment changes; long run returns; inflation expectations mechanism.

Day 7: Disinflation policy reasoning

• Tightening, unemployment effects, and the role of credibility/expectations.

Day 8: Open-economy exchange rate depreciation scenario

• Transmission: NX, inflation pass-through, possible policy response.

Day 9: Open-economy fiscal expansion with high capital mobility

• Interest rate → exchange rate appreciation → NX offset → net output effect.

Day 10: Mixed full exam simulation

• One calculation question, one diagram question, one policy essay question.

How to self-check answers (fast but rigorous)

1. Direction test: If you predict AD increases, output should rise (short run). If your diagram shows output falls, you have a contradiction.
2. Consistency test: If you say “unemployment returns to natural rate,” ensure your explanation includes expectations adjustment.
3. Equation test: In multiplier problems, confirm (Y = AE).
4. Policy trade-off test: If you reduce unemployment short run, inflation must rise somewhere in the narrative under the standard Phillips curve framework.

High-Yield Concept Map (What you must be able to explain under pressure)

Below is a compact but precise map of relationships—use it to quickly structure your exam answers.

AD/AS relationships

• Increase in (G) → AD right → higher output & higher price level in short run.
• Cost-push shock (e.g., energy prices) → SRAS left → lower output & higher inflation.
• Long run: output returns to potential; price level adjusts permanently.

Phillips curve logic with expectations

• Unemployment below natural rate → inflation rises.
• Unemployment above natural rate → inflation falls.
• Persistent expansion leads to higher inflation expectations; unemployment returns to natural rate in long run.

Open economy logic

• Depreciation → NX improves (AD up) but inflation may rise via pass-through (AS left).
• Higher interest rates → capital inflows → appreciation → NX worsens (offsetting AD).
• Policy effectiveness depends on exchange rate regime, capital mobility, and pass-through.

Multipliers and national income

• Equilibrium: (Y = C + I + G + NX)
• Changes in (G) scale equilibrium output by the multiplier, which depends on MPC and tax structure.

Final Exam Readiness Checklist (Before you walk in)

Use this checklist as your final consolidation. If you can confidently do each bullet, you are well-prepared.

Model mastery

• I can draw AD/AS and show correct short-run and long-run outcomes.
• I can derive equilibrium output using a Keynesian cross model algebraically.
• I can explain unemployment and inflation using Phillips curve logic with expectations.
• I can explain open-economy transmission using exchange rate and capital flow channels.

Answer quality

• Every diagram has labelled axes, correct shifts, and a correct textual interpretation.
• Every calculation shows substitution steps and checks for sign errors.
• Every policy answer includes trade-offs and short-run vs long-run implications.

Contextual reasoning

• I can mention South Africa-relevant mechanisms (inflation persistence, exchange-rate pass-through, fiscal constraints, labour market structure) without inventing unsupported numbers.
• I can connect external shocks (global demand, commodity prices, risk premia) to domestic inflation and output.

If you would like, I can also generate a SECO202-style mock exam (with marking guide) tailored to these clusters, or produce institution-specific flashcards aligned to typical South African university exam marking schemes.