ECO3020F Advanced Macroeconomics & Microeconomics Exam Notes

ECO3020F: Advanced Macroeconomics & Microeconomics is a high-level course that builds the analytical tools you need to connect microeconomic foundations to macroeconomic outcomes. These exam notes focus on the concepts, models, and solution techniques most commonly assessed—especially those that appear in South African university economics curricula and typical structured exam formats. The guide also emphasizes how to present answers clearly: define assumptions, derive key relationships, interpret results, and evaluate policy implications with regard to realism in the South African context.

Section 1: Microeconomics Foundations for Advanced Analysis (ECO3020F Level)

Core optimization problems and the logic of choice

At advanced microeconomics level, most questions reduce to two types of problems:

1. Consumer optimization: choose quantities to maximise utility subject to a budget constraint.
2. Firm optimization: choose inputs or outputs to maximise profit (or minimise cost) subject to production technology.

In exams, you are rarely rewarded for memorising results without showing the steps. A strong answer follows this structure:

1. State the objective function (utility or profit).
2. Write the constraint (budget or technology).
3. Set up Lagrangian (or use first-order conditions if the question explicitly gives functional forms).
4. Solve FOCs (and check second-order conditions or constraints).
5. Interpret comparative statics (signs of derivatives and intuition).

Consumer choice: utility maximisation with Lagrangians

A representative exam-style setup:

• Utility: (U(x,y))
• Budget: (p_x x + p_y y = m)

Lagrangian:
[
\mathcal{L} = U(x,y) + \lambda(m – p_x x – p_y y).
]

FOCs:
[
\frac{\partial U}{\partial x} = \lambda p_x,\quad \frac{\partial U}{\partial y} = \lambda p_y,\quad m – p_x x – p_y y = 0.
]

Key interpretation:
[
\frac{\partial U/\partial x}{\partial U/\partial y} = \frac{p_x}{p_y},
]
which states marginal rate of substitution equals relative price.

Exam technique: after solving for (x(p_x,p_y,m)) and (y(p_x,p_y,m)), you typically compute:

• Marshallian (ordinary) demand: the result directly from the utility maximisation.
• Income and substitution effects, especially when asked about normal/inferior goods.

Example: Cobb–Douglas utility

Let:
[
U(x,y)=x^\alpha y^{1-\alpha}, \quad 0<\alpha<1.
]
Solution implies:
[
x=\alpha \frac{m}{p_x},\quad y=(1-\alpha)\frac{m}{p_y}.
]

Comparative statics are straightforward:

• Higher income (m) increases both goods (normal goods).
• Higher price (p_x) decreases demand for (x) and leaves (y) unchanged except through income effects (which cancel under Cobb–Douglas due to constant budget shares).

Why this matters in advanced exams: many later macro questions require understanding how price changes transmit to consumption patterns and aggregate demand—especially in models with consumption goods, real wages, or tax incidence.

Firm behaviour: cost minimisation, profit maximisation, and duality

Advanced micro exams often include duality: proving results in either the primal (profit/cost) or dual (cost function) form.

Production and the cost function

Given a technology:
[
q = f(K,L),
]
with input prices (w) (wage) and (r) (capital cost), a firm can choose inputs to minimise cost for a target output (q):
[
\min_{K,L} ; wL + rK \quad \text{s.t. } q \le f(K,L).
]

The cost function is:
[
C(q,w,r).
]

From duality:

• The firm’s profit maximisation can be expressed via cost:
  [
  \max_q ; \pi = p q – C(q,w,r).
  ]

FOC:
[
p = \frac{\partial C}{\partial q} = MC(q).
]
So marginal cost equals output price in a competitive profit-maximising firm.

Market structure and strategic behaviour (micro-to-macro link)

Although ECO3020F’s title includes macro, advanced micro content frequently appears through imperfect competition and markup pricing, which then feeds into macro aggregates (inflation dynamics, pass-through, and output gaps).

Monopoly and Lerner index

For a monopoly with constant elasticity demand, the markup over marginal cost depends on elasticity:
[
\frac{p – MC}{p} = \frac{1}{\varepsilon},
]
where (\varepsilon) is the (absolute value of) demand elasticity.

Exam interpretation:

• If demand is less elastic ((\varepsilon) smaller), monopoly markup is larger.
• In macro, larger markups can amplify inflation when costs rise, affecting real incomes and consumption.

Oligopoly and Nash equilibrium logic

A standard exam question may provide a payoff matrix or best-response functions. The key is:

1. Derive best responses for each firm/player.
2. Solve for intersection(s).
3. State equilibrium and evaluate welfare implications.

South African context: exams sometimes ask you to discuss competition policy relevance for pricing power in sectors like telecommunications, basic food categories, and banking/insurance—without requiring firm-specific legal detail.

Demand theory: elasticity, substitution/complementarity, and welfare

Welfare economics underlies many macro policy discussions (e.g., tax incidence, welfare losses from unemployment, or efficiency of transfers).

Price elasticity and total revenue

[
\varepsilon_{p} = \frac{dQ}{dP} \cdot \frac{P}{Q}.
]

Total revenue (TR=P\cdot Q):

• If (|\varepsilon_p|>1), price increases reduce revenue.
• If (|\varepsilon_p|<1), price increases raise revenue.

Consumer surplus and deadweight loss

With demand curve (D(q)) (in price-space), consumer surplus (CS) is the area under demand above price. If a tax raises price to consumers:

• CS falls.
• Government revenue rises.
• Deadweight loss occurs due to reduced quantity traded beyond tax-financed transfers.

A good answer includes:

• a diagram description (even if diagrams aren’t required),
• a conceptual breakdown of effects,
• a statement linking DWL to elasticity.

Counter-argument to memorised claims: elasticity measures matter, but empirical estimation can be hard; policy evaluations often differ because elasticity differs by product category and time horizon (short run vs long run).

Micro welfare with taxes and incidence (exam-critical)

Tax incidence depends on elasticities, not statutory burden.

If a per-unit tax (t) is imposed on sellers:

• the price paid by consumers rises by less than (t) if demand is more elastic than supply (or vice versa).

You typically express incidence shares as:
[
\text{Share on consumers} \propto \text{elasticity of demand}, \quad
\text{Share on producers} \propto \text{elasticity of supply}.
]

South African exam relevance:

• Excise taxes and VAT-like mechanisms influence food and fuel prices.
• The distributional consequences depend on elasticity across household income groups.

Transition to microfoundations for macro models

The ECO3020F macro component often builds on microeconomic foundations—particularly how households form consumption plans and how firms set prices/wages.

In practice, exam questions may ask you to:

• derive an Euler equation from intertemporal utility,
• explain how demand shifts affect output,
• interpret how policy changes (taxes, interest rates) transmit to consumption.

Your micro foundation skill set must therefore include:

• intertemporal preferences,
• budget constraints over time,
• firm pricing conditions and marginal productivity.

Section 2: Advanced Macroeconomics Models and Core Results

Measuring macro: aggregates, real vs nominal, and adjustment

Advanced macro questions often begin with a measurement or interpretation component.

Nominal variables vs real variables

Nominal GDP grows due to both price changes and output changes. Real GDP adjusts for inflation:
[
\text{Real GDP} = \frac{\text{Nominal GDP}}{P},
]
where (P) is a price index.

Similarly:

• interest rates: nominal vs real
  [
  1+r_{real} = \frac{1+i_{nominal}}{1+\pi}.
  ]

Exam tip: when interpreting policy, always specify whether the relevant rate is real or nominal.

AD-AS and dynamic extensions

The Aggregate Demand (AD) – Aggregate Supply (AS) framework is often assessed conceptually even in advanced courses. ECO3020F may ask you to explain equilibrium and stability under different shock types.

Keynesian cross and IS-type intuition

In many exams, the logic follows:

• consumption depends on income,
• investment depends on interest rate and expectations,
• net exports depend on relative income/real exchange rate.

The demand side equilibrium condition can be sketched as:
[
Y = C(Y – T) + I(i) + G + NX(\text{real exchange rate}, Y, Y^*).
]

Short-run vs long-run supply

• Short run: output can deviate from potential due to demand fluctuations, with prices/wages sticky or slow to adjust.
• Long run: output returns to potential (full employment), with flexible prices/wages and monetary neutrality.

Counter-argument: In reality, persistent unemployment, skills mismatches, and hysteresis can make “long run” effects non-trivial—so output might not revert quickly.

Solow growth model (if included) vs modern growth intuition

Some ECO3020F curricula include growth theory refreshers. Even if not heavily examined mathematically, being able to interpret mechanics matters.

Solow: saving, capital accumulation, and steady state

Core equation:
[
\dot{k} = s f(k) – (\delta + n)k,
]
where:

• (k) is capital per worker,
• (s) is savings rate,
• (\delta) depreciation,
• (n) population growth (or labour growth).

Steady state solves:
[
s f(k^) = (\delta + n)k^.
]

Policy link:

• raising (s) increases (k^*) but not long-run growth rate (in basic Solow).
• sustained long-run growth comes from technological progress.

South African relevance:

• debates about whether low growth is due to capital constraints, human capital, or technology/TFP.
• infrastructure and skills policy can be framed as influencing effective productivity, i.e., technological progress or the efficiency of capital use.

RBC vs New Keynesian: microfoundations of macro

Advanced macro exams commonly ask you to compare frameworks.

Real Business Cycle (RBC) model intuition

• business cycles are driven by real shocks (technology shocks, preferences).
• prices and wages are flexible.
• monetary policy mainly affects nominal variables; real effects come from real shocks.

New Keynesian model intuition

• wages/prices are sticky due to nominal rigidities.
• monetary policy has real effects in the short run.

The backbone of NK is often:

1. New Keynesian Phillips Curve (NKPC): inflation responds to the output gap.
2. Intertemporal Euler equation: consumption responds to expected real interest rates.

Exam question pattern: “Explain how a negative demand shock affects output and inflation in RBC vs NK.” You should explicitly state:

• RBC: output declines, inflation effect depends on flexible prices; monetary neutrality often holds.
• NK: output gap worsens, inflation falls due to weaker marginal costs but with timing due to stickiness.

Dynamic stochastic general equilibrium (DSGE) basics

ECO3020F-level understanding typically includes:

• state variables,
• shocks and expectations,
• the role of rational expectations,
• equilibrium conditions.

Linearisation and policy rules

A typical exam question may present a linear model:
[
x_t = A \mathbb{E}t[x{t+1}] + B x_{t-1} + C u_t,
]
and ask you to solve for coefficients under a given policy rule like a Taylor-type interest rate reaction:
[
i_t = \rho i_{t-1} + (1-\rho)(\phi_\pi \pi_t + \phi_y y_t).
]

Stability condition: In many textbook NK settings, you need (\phi_\pi>1) for determinacy (exact conditions depend on model form). In exam answers, you should state the direction: too weak an inflation response leads to indeterminacy/explosive paths.

Monetary policy transmission mechanisms

Advanced macro often assesses your ability to explain transmission channels clearly:

1. Interest rate channel: policy affects real interest rates → affects consumption and investment.
2. Expectations channel: policy credibility changes expectations of future inflation/interest rates.
3. Exchange rate channel: changes relative returns → affects net exports.
4. Credit/balance sheet channel: affects borrowing costs and collateral value.

Credit and balance sheet channel

Especially relevant for economies with banking-sector dominance:

• higher policy rates raise default risk and reduce credit supply,
• consumption of durables and investment become constrained.

In a South African context, you can mention:

• household debt sensitivity to interest rates,
• the role of banks in transmitting policy rates to the economy.

Fiscal policy: multipliers, crowding out, and Ricardian equivalence

A strong exam answer distinguishes:

• short-run multipliers (where monetary policy might accommodate),
• long-run outcomes (where debt dynamics and supply constraints matter).

Ricardian equivalence (and why it can fail)

In theory, if households anticipate future taxes, they save to offset government borrowing. But in reality:

• liquidity constraints make borrowing impossible,
• households may not forecast perfectly,
• political commitment to future taxes is uncertain.

Counter-argument: even if forward-looking, the fiscal timing matters; deficits can still shift demand in the short run.

Exchange rates, inflation, and pass-through

Many macro exams include open-economy aspects: exchange rate depreciation can:

• raise import prices (direct inflation effect),
• affect competitiveness and net exports (output effect),
• interact with monetary credibility and forward-looking behaviour.

Pass-through differs across countries and time horizons depending on:

• exchange rate pass-through to domestic prices,
• hedging behaviour,
• inflation expectations.

For South Africa, you can frame discussions around episodes where exchange rate volatility coincided with inflation concerns, while emphasising that the exact pass-through is empirical.

Section 3: Micro-to-Macro Links, Labour Markets, and Policy in Advanced Settings

Labour markets and unemployment: efficiency wages, bargaining, and search frictions

Even if ECO3020F focuses on standard macro, advanced macro often needs labour-market structure to explain persistence in unemployment and wage dynamics.

Efficiency wage perspective

Firms may pay wages above the market-clearing rate to:

• reduce shirking,
• attract better workers,
• improve worker productivity.

Implication:

• higher unemployment can reduce the need to raise wages, but wages may not fully adjust downward quickly.
• can create persistent unemployment and slow real adjustment.

Wage bargaining and sticky wages

If wages are negotiated through bargaining:

• wages adjust sluggishly,
• output and inflation respond differently to shocks.

In exams, state:

• what causes sticky wages (contracting, bargaining power, adjustment costs),
• how that generates business-cycle amplification.

Search and matching (stylised)

With search frictions:

• unemployment persists because matching takes time,
• policy affects unemployment through job-finding probability and vacancy creation.

An exam might ask you to reason about labour market tightness:

• tighter labour markets reduce unemployment,
• unemployment benefits influence job search incentives.

Sticky prices and real effects of nominal shocks

New Keynesian macro gives a coherent mechanism:

• prices cannot adjust instantly,
• so demand changes lead to real output fluctuations.

Menu costs and price adjustment limitations

Suppose firms face costs of changing prices. Then:

• they keep prices fixed for some time,
• inflation arises through staggered adjustments.

Exam framing:

• a monetary expansion increases expected inflation/lowers real rates,
• firms experience higher demand,
• output rises temporarily because prices are sticky.

Consumption-savings choices: Euler equation and intertemporal policy impact

Many ECO3020F exams require intertemporal reasoning.

Representative household with CRRA utility

Common form:
[
U(C_t)=\frac{C_t^{1-\sigma}}{1-\sigma}.
]

Budget constraint (schematically):
[
A_{t+1} = (1+r_t)A_t + Y_t – C_t – T_t.
]

Euler equation:
[
C_t^{-\sigma} = \beta (1+r_t) \mathbb{E}t[C{t+1}^{-\sigma}].
]

Log-linearised intuition:

• if real interest rates rise, households shift consumption toward the future → current consumption falls.
• consumption smoothing depends on (\sigma) and expectations.

Policy implication:

• monetary policy affects interest rates → consumption and investment respond, shifting output.

Investment and Tobin’s q; real interest rate effects

Investment models connect micro behaviour to macro output.

Costly adjustment and investment hysteresis

A common advanced micro-to-macro investment logic:

• adjusting capital is costly,
• firms respond to expected returns, not only current rates.

You may be asked to derive the sign of investment changes:

• higher expected profitability or lower real rates → higher investment.

Financial constraints and acceleration principle

If investment depends on internal funds or balance sheet strength:

• downturns reduce profits,
• reduced collateral reduces credit,
• which reduces investment further (amplification).

South African relevance:

• emerging-market credit cycles often show strong sensitivity to global financial conditions and domestic interest rates.

Inflation dynamics: output gap vs marginal cost

A key NK concept is the relationship between inflation and economic slack.

Output gap interpretation

Output gap is:
[
\text{gap}_t = Y_t – Y_t^{},
]
where (Y_t^{}) is potential output (or natural level).

A negative gap implies weak demand:

• firms face lower marginal costs (or weaker pricing power),
• inflation declines with lags.

Exam writing: always tie inflation direction to pricing power and marginal cost, not only “demand falls → inflation falls.”

Policy evaluation: welfare, trade-offs, and credibility

Advanced exam answers should address:

• short-run stabilisation vs long-run efficiency,
• the role of expectations,
• welfare loss functions.

Loss function and trade-off statement

A typical simplified NK welfare proxy:
[
L_t = \frac{1}{2}\left(\pi_t^2 + \lambda (y_t – y^*)^2\right),
]
meaning:

• high inflation is costly,
• output deviations are costly.

Policy rule: selecting monetary policy should balance these.

Credibility and expectations channel

Credible central banks reduce the cost of stabilisation because expectations align:

• if households and firms expect lower inflation, current inflation dynamics improve.
• policy “works faster,” output volatility may be lower.

Counter-arguments and realism for exams

Strong marks often come from demonstrating conceptual flexibility. Typical counterpoints:

• Sticky prices may be less severe in some sectors (e.g., energy with rapid pricing updates).
• Indexation can change NK dynamics by slowing inflation adjustment.
• Monetary-fiscal interactions: if fiscal dominance occurs, monetary credibility weakens, raising inflation persistence.

In South Africa, you can mention the importance of credible inflation targeting frameworks while keeping reasoning general unless the exam question specifies a particular policy episode.

Section 4: Quantitative Problem-Solving Skills for ECO3020F Exams (Derivations, Diagrams, and Interpretation)

How to structure mathematical answers under time pressure

A typical exam in advanced micro/macro rewards method. Use this “standard template”:

1. State assumptions (e.g., rational expectations, competitive markets, sticky prices).
2. Write model equations (Euler equation, production, budget, demand).
3. Solve step-by-step (algebra and key derivatives).
4. Interpret signs (increase/decrease and why).
5. Link to economic intuition (markets clear? sticky? elasticities?).
6. Conclude with the exact quantity asked.

Avoid:

• jumping to final results without showing key steps,
• mixing up nominal/real or levels/logs,
• inconsistent variable definitions.

Micro derivation practice: comparative statics and welfare

Comparative statics: a checklist

When asked: “What happens to (x) when (p_x) increases?” you should specify:

1. substitution effect (relative price change),
2. income effect (real purchasing power change),
3. sign using normal/inferior classification.

For welfare:

• change in consumer surplus depends on shape and elasticity,
• taxes cause deadweight loss due to reduced trade relative to efficient allocation.

Example case: tax on a good with quasi-linear utility

Suppose:
[
U(x,y)=u(x)+y,
]
with (y) as a numeraire and budget (p_x x + y = m).

Then:

• consumer surplus and Hicksian elasticity calculations can simplify.
• deadweight loss formulas can be written in terms of elasticity and tax rate.

Even if functional form is not exactly given, exam questions may ask you to compute:

• approximate DWL using second-order approximation:
  [
  DW L \approx \frac{1}{2} t^2 \cdot Q \cdot |\varepsilon|.
  ]
  This is a common approach; always verify the variables the question provides.

Macro derivation practice: IS–NK and policy shocks

A common macro exam question uses a simplified system:

1. IS (Euler) relation for output gap.
2. NKPC for inflation.
3. Policy rule for nominal interest rate.

IS intuition

A stylised IS:
[
x_t = \mathbb{E}t[x{t+1}] – \frac{1}{\sigma}(i_t – \mathbb{E}t[\pi{t+1}] – r^*),
]
where:

• (x_t) is output gap,
• (i_t) nominal rate,
• (r^*) natural real rate.

Policy increase (higher (i_t)) reduces the real rate gap:

• output gap falls.

NKPC intuition

Stylised:
[
\pi_t = \beta \mathbb{E}t[\pi{t+1}] + \kappa x_t.
]
Then:

• if (x_t<0), inflation falls.

Exam response: combine equations to explain dynamics after a shock, not just static sign.

Diagram competence without over-reliance

You may be asked to draw:

• AD-AS,
• labour market (supply/demand),
• monopoly pricing diagram (MR=MC, P above MC),
• unemployment and wage determination.

Even when diagrams aren’t graded for artistry, you must label:

• axes,
• curves,
• equilibrium points,
• direction of shifts.

For NK/IS, if you draw:

• IS: downward relation between inflation/interest and output gap (depending on exact representation).
• NKPC: upward relation between output gap and inflation.

Then policy shock shifts the policy-implied real rates; interpret the intersection.

Worked macro examples you should be able to replicate

Example 1: effect of a demand shock under sticky prices

Consider an adverse demand shock:

• lowers consumption/investment demand,
• output gap becomes negative.

Under NKPC:

• lower (x_t) reduces inflation.
  Under IS:
• output gap declines due to lower effective demand.

A full answer:

1. define negative demand shock,
2. show output gap falls,
3. substitute into NKPC → inflation falls with expectations,
4. mention lags and expectations if required.

Example 2: monetary tightening (policy rate increase)

Assume central bank raises nominal rate (i_t).

• real rate increases relative to expected inflation,
• consumption and investment fall,
• output gap declines.

Then:

• inflation declines due to negative slack.

You then discuss welfare trade-off:

• inflation decreases (good),
• output falls (bad),
• final net welfare depends on relative weights.

Common pitfalls that cost marks

1. Nominal/real confusion: using nominal interest rate as if it were real without adjusting for expected inflation.
2. Sign errors in elasticities: price elasticity is typically negative; use absolute value carefully.
3. Forgetting constraints: FOCs must satisfy budget constraints or output technology.
4. Not interpreting results: “(x) increases” without saying why it increases is typically incomplete.
5. Mixing frameworks: claiming RBC implies monetary policy has large real effects without relaxing assumptions.
6. Overgeneralising: assuming fixed conclusions regardless of horizons (short-run vs long-run).

South African policy framing in exam answers (without needing local datasets)

South African contexts that are safe to mention at conceptual level:

• inflation targeting and monetary credibility,
• VAT/excise impacts on cost-of-living,
• unemployment and youth labour market issues,
• load shedding and electricity constraints affecting supply and investment,
• currency volatility and import price pass-through.

Key constraint: don’t invent specific numeric values (like “inflation was 6% in 2022”) unless the exam question or allowed materials specify them. Use qualitative reasoning unless instructed.

Section 5: Integrated Practice—Model Interpretation, Policy Design, and Exam Readiness

Turning theory into exam-ready narratives

Advanced ECO3020F answers are strongest when you “translate” algebra into a coherent economic story.

Use a three-paragraph logic:

1. Mechanism (what changes and through which channel).
2. Model implication (which equation(s) govern the outcome).
3. Outcome and welfare/policy trade-off (what happens to inflation/output/unemployment and why it matters).

Example narrative skeleton: fiscal expansion

Suppose fiscal expansion increases government spending (G).

• Short run: increases aggregate demand → output gap rises.
• NKPC: higher output gap increases inflation.
• Policy interaction: if central bank accommodates, output effect may be larger; if not, real interest rates rise, reducing multiplier.

Then discuss:

• crowding out via higher interest rates,
• debt sustainability concerns over long run,
• distributional impacts via tax financing.

Monetary-fiscal interactions and policy regimes

Inflation targeting credibility

A typical exam might ask you to explain how commitment affects inflation and output:

• credible policy lowers expected inflation,
• stabilisation costs are reduced.

Fiscal dominance

If fiscal policy forces central bank to accommodate deficits:

• expected inflation rises,
• inflation becomes more persistent,
• output effects could become distorted.

Answer approach:

• define fiscal dominance,
• state expectations mechanism,
• connect to NK equations (inflation depends on expectations).

Labour market policy and macro outcomes

Given unemployment persistence concerns, many advanced macro exams include labour market policies.

Unemployment benefits and search

• More generous benefits can increase reservation wages and prolong job search.
• In NK/IS contexts, that can alter consumption and unemployment dynamics.
• Yet benefits can also stabilise demand via income smoothing if financed sustainably.

Your exam conclusion should acknowledge:

• trade-off between insurance and incentives,
• heterogeneity by duration of unemployment and skill levels.

Active labour market programmes (ALMPs)

Examples you can discuss qualitatively:

• training programmes,
• job placement services,
• wage subsidies.

Mechanism:

• improve matching efficiency,
• increase job-finding probability,
• reduce structural unemployment if skills are relevant.

Counter-argument:

• if programmes are poorly targeted, they may have low effectiveness.
• measurement issues arise in evaluating outcomes.

Competition policy, markups, and inflation dynamics

Because micro and macro meet through pricing power:

Markups and the inflation pass-through

If firms have stronger market power:

• cost shocks may be passed through to prices more aggressively,
• inflation may respond more strongly to output gaps.

For exam answers:

• link markup behaviour to marginal cost and pricing rules,
• mention how competition affects the sensitivity of inflation to slack.

Interpreting empirical-looking exam questions (stylised data)

Some ECO3020F papers give a small dataset (monthly/quarterly) or a table of key macro variables. Your job is to:

1. identify the shock (demand vs supply vs monetary),
2. relate signs to model predictions,
3. explain plausibility.

Shock identification guide (qualitative)

• Negative supply shock: output falls, inflation rises.
• Negative demand shock: output falls, inflation falls.
• Monetary tightening: output falls, inflation falls after lags.
• Demand shock with sticky expectations: inflation might fall less initially.

When asked:

• “Which shock best explains the pattern?” you justify with model-consistent signs.
• If multiple shocks can explain, you mention additional evidence needed (e.g., commodity prices for supply shocks, interest rate changes for monetary shocks).

Comprehensive integrated exam scenarios (practice)

Below are high-quality integrated scenarios that combine micro concepts (elasticity, markups, labour bargaining) with macro (output gap, inflation, policy rules). These are written in a way that mirrors typical exam prompts.

Scenario A: Tax increase on consumption with sticky prices

Prompt type: “Government imposes a tax on a consumption good. Using micro theory and a simple macro model, explain effects on consumption, output, and inflation.”

A strong answer must include:

1. Micro:
   • tax increases consumer price for the good.
   • demand falls by elasticity: more elastic demand → larger quantity reduction.
2. Macro:
   • if the tax reduces consumption demand, output gap falls.
   • NKPC: negative output gap reduces inflation (in the short to medium run).
3. Policy response:
   • central bank reaction function: if monetary policy tightens further, output contraction strengthens.
4. Distributional commentary:
   • incidence depends on elasticities and household budget shares.
   • low-income households may be more affected if the good is a larger expenditure share and demand is less elastic in essentials.

Scenario B: Wage rigidity due to bargaining and unemployment persistence

Prompt type: “Explain why unemployment might not return quickly to its natural rate after a recession.”

A strong answer:

1. labour market mechanism:
   • wages adjust slowly due to bargaining contracts,
   • efficiency wages or search frictions create persistence.
2. macro linkage:
   • persistent output below potential leads to continued negative slack.
3. inflation:
   • inflation may fall gradually; expectations matter.
4. policy:
   • active labour market policies could help restore matching efficiency,
   • monetary policy alone may not solve structural unemployment.

Scenario C: Increased market power and inflation responsiveness

Prompt type: “How would an increase in market power affect the inflation-output relationship?”

A strong answer:

1. micro: markups increase; pricing power greater.
2. macro:
   • inflation may respond more to cost shocks (marginal costs) or may not fall as much when output gap is negative, depending on the model’s markup mechanism.
3. evaluation:
   • competition policy becomes macro-relevant as it affects inflation dynamics and welfare.

Building your own “exam sheet” of key formulas

For ECO3020F, you should memorise only what you can deploy quickly and correctly. The following are high-yield formulas/relationships you may encounter:

Micro high-yield

• MRS equals price ratio:
  [
  \frac{MU_x}{MU_y}=\frac{p_x}{p_y}.
  ]
• Monopoly markup (Lerner):
  [
  \frac{p-MC}{p}=\frac{1}{\varepsilon}.
  ]
• Competitive pricing:
  [
  p=MC.
  ]
• Tax incidence depends on elasticities:
  • share on consumers/producers depends on relative elasticities.

Macro high-yield

• Real rate relation:
  [
  r \approx i – \pi^e.
  ]
• Euler equation logic:
  [
  C_t^{-\sigma}=\beta(1+r_t)\mathbb{E}t[C{t+1}^{-\sigma}].
  ]
• NKPC shape:
  [
  \pi_t=\beta\mathbb{E}t[\pi{t+1}]+\kappa x_t.
  ]
• IS shape:
  [
  x_t=\mathbb{E}t[x{t+1}]-\text{(real rate gap term)}.
  ]

South African exam readiness: writing clearly under assessment style

Even without knowing the exact marking rubric of your institution, typical South African university economics exam marking emphasises:

1. Clarity of definitions (output gap, natural rate, elasticity, marginal rate of substitution).
2. Correct sequencing of derivation (start with assumptions → derive → conclude).
3. Economic interpretation (what does the sign mean; why).
4. Consistency across parts of the answer (units, variables, and timing).
5. Realistic caveats (expectations, stickiness, credibility, liquidity constraints).

A good strategy is to practise writing “micro-mechanism → macro-implication → policy relevance” on every question, even if only briefly.

Final checklist before submitting an exam script

Use this checklist as a mental guide:

• Have I defined all variables and assumptions before using them?
• Did I show the key steps in derivations (not just final results)?
• Did I use correct signs and interpret elasticity properly?
• For macro: did I clearly distinguish short-run vs long-run effects?
• Did I link monetary/fiscal actions to transmission channels?
• Did I address trade-offs and welfare, not only efficiency?
• Did I maintain internal consistency of notation and timing ((t), (t+1), expectations)?

Institution-cluster focus (UCT economics study guide collection alignment)

This guide aligns with University of Cape Town (UCT) Economics Study Guides expectations in depth and rigour: it emphasises microfoundations, consistent equilibrium logic, and the ability to integrate micro and macro reasoning in policy contexts. While the notes are not restricted to UCT-specific coursework materials, the style supports the kind of structured, analytical answers commonly demanded in advanced economics examinations at South African universities and related TVET-articulation contexts where advanced reasoning and model interpretation are assessed.

If you want, I can also generate model exam questions with full worked solutions specifically in the style of UCT advanced economics papers (for ECO3020F-style topics), including separate sets for: (1) micro derivations, (2) macro shocks and policy, and (3) integrated micro-macro policy trade-offs.