Weekly IB Economics Analytics Report

AD–SRAS shifts under policy changes: consistent misconceptions

This week’s quizzes show strong performance on elasticity and basic supply concepts but recurring errors when identifying which AD/AS curve shifts under different policy scenarios.

2026-W24

AD–SRAS shifts under policy changes: consistent misconceptions

This week’s quizzes show strong performance on elasticity and basic supply concepts but recurring errors when identifying which AD/AS curve shifts under different policy scenarios.

Published June 21, 2026

Total quiz attempts

72

Average score

77.7%

Overall question accuracy

75.9%

Average time per question

41.2 s

Top weakness (unit)

Macroeconomics — 3.5 / 3.6 (AD–SRAS / LRAS)

1. Weekly Overview

Students generally score well overall but struggle with AD–SRAS/LRAS policy effects.

Aggregate results (72 attempts, avg score 77.7%) show clear strengths in micro topics like price elasticity and supply responsiveness, while the weakest area is applying the AD–SRAS and AD–SRAS–LRAS diagrams to monetary and fiscal policy decisions—especially distinguishing short‑run demand shifts from long‑run supply changes. Several conceptual and calculation items also took unusually long to answer, suggesting either careful work or hesitation.

Student takeaway: Prioritise revising AD–SRAS and LRAS diagram shifts for policy scenarios, then practise a few timed macro calculations (GDP components and real vs nominal interest).

2. Key Patterns

Main Insights

Frequent errors identifying which curve shifts in AD–SRAS short‑run cases

Several medium‑difficulty AD–SRAS items about interest rate cuts, QE and fiscal changes recorded very low correct rates (many at or near 0%), indicating students mix up demand and supply channels in short‑run diagrams.

Advice: Review the standard AD–SRAS diagram: if policy changes affect aggregate demand (interest rates, government spending, QE), practice drawing AD shifts; if they directly change costs or productive capacity, practice SRAS/LRAS shifts.

Confusion about long‑run effects (LRAS) from sustained monetary policy

Questions about long‑run shifts (LRAS) when monetary policy remains tight for extended periods had very low correct rates, suggesting difficulty linking prolonged low investment to changes in productive capacity.

Advice: Distinguish short‑run demand responses from long‑run supply effects: prolonged reductions in investment can reduce capital and shift LRAS left — practice 2–3 AD–SRAS–LRAS scenarios and state the mechanism (investment → capital stock → LRAS).

Timed calculation and application questions consume much time and sometimes reduce accuracy

Several calculation and application items (price ceilings, GDP export calculation, real interest return) show very long average times and mixed accuracy, indicating either careful working or uncertainty with formulas.

Advice: Practice a short set (5–10) of timed macro calculations: GDP components (Y = C + I + G + (X − M)) and converting nominal to real returns (real ≈ nominal − inflation). Time yourself to 2–4 minutes per calculation to build fluency.

3. Revision Plan

Priority Areas

AD shifts vs SRAS/LRAS shifts · 3.5 / 3.6

Most incorrect answers concentrated on which curve moves under monetary and fiscal policy.

Action: Draw 6 labelled AD–SRAS–LRAS diagrams: short‑run demand changes (interest rate cuts, QE, gov spending) vs supply/capacity changes; write one short sentence explaining the mechanism for each.

Long‑run supply determinants · 3.5

Sustained policy effects were not linked to LRAS movement in many responses.

Action: Review determinants of LRAS (capital, labour, technology) and practise 3 examples where decreased investment shifts LRAS left.

Macro calculations: GDP components & real vs nominal interest · 3.1 / 3.3

High time spent and errors on basic calculations slowed performance.

Action: Do 10 timed practice problems (2–4 minutes each) on GDP component algebra and converting nominal to real returns using both approximation and exact formula.

Micro: elasticity and supply responsiveness (maintenance) · 2.5 / 2.6

High accuracy here is a strength — maintain it.

Action: Quick revision (15–20 minutes): summary notes and 5 mixed questions to keep fluency.

4. Question Evidence

Featured Questions

Most Wrong Questions

QuestionTopicUnitAttemptsCorrectWrongAvg Time
An economy is experiencing demand-deficient unemployment and output is below potential. The government of Ibonomica decides to increase unemployment benefits and raise public sector wages. What happens to aggregate demand in the AD–SRAS model in the short run?Macroeconomics3.670.0%100.0%37.5 s
For an extended period, the European Central Bank (ECB) keeps interest rates very high to fight inflation, causing firms across the euro area to cut back on long-term investment projects. In the AD–SRAS–LRAS model, which curve is most likely to shift in the long run due to this sustained monetary stance, and in which direction?Macroeconomics3.570.0%100.0%1.1 min
Facing persistent demand-pull inflation, the Bank of England decides to increase its base rate and signals further tightening. According to the AD–SRAS model, which curve shifts as a result of this policy decision, and in which direction?Macroeconomics3.5922.2%77.8%36.2 s
The European Central Bank (ECB) launches a large-scale asset purchase programme (quantitative easing) to prevent deflation in the euro area. In the standard AD–SRAS model, which curve shifts first in response to this policy, and in which direction?Macroeconomics3.51241.7%58.3%53.4 s
The central bank of Ibonomica announces a significant cut in its policy interest rate to combat a recession and high unemployment. In the AD–SRAS diagram, which curve is most likely to shift in the short run, and in which direction?Macroeconomics3.51450.0%50.0%46.3 s

Most Correct Questions

QuestionTopicUnitAttemptsCorrectWrongAvg Time
Suppose the government of Ibonomica uses contractionary fiscal policy—reducing government spending and increasing taxes—to close an inflationary gap in a monetarist AD–SRAS–LRAS model. Considering the demand-side channel, which curve shifts, in what direction, and what is the main long-run implication?Macroeconomics3.69100.0%0.0%1.5 min
Which factor is most likely to make the demand for a good more price‑elastic?Microeconomics2.51090.0%10.0%23.3 s
Which factor would make supply more inelastic?Microeconomics2.68100.0%0.0%23.0 s
How is the economy affected when interest rates rise significantly?Macroeconomics3.57100.0%0.0%10.5 s
The economy is at or very close to full employment when the government of Ibonomica unexpectedly raises government spending to boost popularity before an election. Focusing on the demand-side effect, which curve shifts in the short run and in which direction?Macroeconomics3.67100.0%0.0%25.7 s

Most Time Spent Questions

QuestionTopicUnitAttemptsCorrectWrongAvg Time
What is one major effect of a price ceiling set below equilibrium price?Microeconomics2.7475.0%25.0%27.1 min
As the time period considered becomes longer, the price elasticity of demand for most goods tends to:Microeconomics2.5771.4%28.6%8.3 min
When does allocative efficiency occur?Microeconomics2.34100.0%0.0%7.3 min
Country C has a nominal GDP of $950 billion. Consumption is $500 billion, Investment is $150 billion, Government spending is $200 billion, and Imports are $80 billion. Calculate the value of Exports (in billions of dollars).macroeconomics3.1450.0%50.0%3.1 min
A person deposits $8,000 in a savings account for one year at a nominal interest rate of 3%. During the same period, the inflation rate is 1.5%. Calculate the real return on the person’s savings at the bank.macroeconomics3.340.0%100.0%2.0 min

5. Conclusion

Next steps

Focus next study time on clear, labelled AD–SRAS–LRAS diagrams and 10–15 minutes of timed macro calculations; practise explaining the mechanism (why a policy shifts AD vs SRAS vs LRAS) in one sentence for each example.

Note: This weekly report is automatically generated and may contain mistakes. Always double-check key points before using them for revision.

This report summarises anonymized aggregate quiz activity and patterns from group-level data only; it does not include or imply any individual student’s performance.

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