2026-W23
AD/AS and supply-side shifts caused most errors this week
Aggregate quiz data show strong mastery of simple demand-side policy effects but recurring confusion about supply-side shifts (SRAS vs LRAS) and multi-effect diagrams.
Published June 14, 2026
Total attempts (week)
141
Active learners
29
Average score
76.2%
Overall question accuracy
74.7%
Average time per question
20.1s
1. Weekly Overview
Supply-side curve shifts were the weakest area this week.
Class-level performance was solid overall (average score ~76%) with consistent success on straightforward demand-side questions (interest rates, taxes). However, the largest errors concentrated in Unit 3.2 macro topics that require distinguishing SRAS vs LRAS and tracing the short- vs long-run consequences of wage, technology and institutional changes. Time-on-question was unusually high for multi-effect micro diagrams, indicating hesitation or extra working through combined shifts.
Student takeaway: Focus next on Unit 3.2: practice when and why SRAS and LRAS shift (technology, wages, institutions) and rehearse labelled AD/AS diagrams that separate short-run and long-run effects.
2. Key Patterns
Main Insights
Confusion distinguishing SRAS vs LRAS when technology or capacity changes
The weakest item (correct rate ~21.9%) asked which curve shifts when technology is wiped out; many students selected incorrect curves or directions, showing uncertainty about which curves represent short-run versus long-run productive capacity.
Advice: Revise the definitions and diagrams for SRAS and LRAS: link technological change and capital destruction to reductions in productive capacity (LRAS left), and practice labelling both SRAS and LRAS shifts when appropriate.
Strength on straightforward demand-side policy effects
Several AD questions had perfect accuracy (100%), notably those on interest rate cuts and higher income taxes reducing AD; this shows reliable understanding of basic monetary and fiscal transmission to aggregate demand.
Advice: Keep using clear AD reasoning steps (consumer spending, investment, net exports) and apply them to slightly more complex contexts (e.g., combine with simultaneous supply shocks).
Multi-effect diagrams are time-consuming and error-prone
Micro questions that combine opposing effects (e.g., cost-saving AI vs negative media) produced very long average times and below-average accuracy, suggesting students spend a lot of time trying to reconcile simultaneous shifts.
Advice: Practice breaking multi-effect diagram problems into steps: (1) identify each individual effect and its direction, (2) draw each shift separately, (3) combine and annotate net outcomes (price, quantity, welfare).
3. Revision Plan
Priority Areas
Short-run vs long-run supply (SRAS vs LRAS) · 3.2
Lowest accuracy on technology/capacity shift questions; students confuse which curve represents productive capacity.
Action: Work through 5 labelled AD/AS diagrams showing technology loss, productivity gains, and temporary shocks; write one-sentence explanations for curve choice.
Wages, unemployment and AS · 3.2
Errors on questions about nominal wage rises and payroll tax changes indicate unclear links between labour costs, SRAS and unemployment.
Action: Practice causal chains: wage → cost of production → SRAS position → price/output/unemployment; use two worked examples for unions and for tax cuts.
Exchange rates and aggregate demand · 3.2
Mixed answers on depreciation effects suggest inconsistent treatment of net exports component of AD.
Action: Drill 4 scenarios of currency appreciation/depreciation and list impacts on exports, imports, AD and AD curve shift direction.
Multi-effect supply/demand diagrams · 2.2
High time spent and lower accuracy when multiple opposing effects are present.
Action: Practice decomposing combined shifts on paper: draw separate diagrams for each effect then overlay and annotate net changes.
4. Question Evidence
Featured Questions
Most Wrong Questions
| Question | Topic | Unit | Attempts | Correct | Wrong | Avg Time |
|---|---|---|---|---|---|---|
| Due to an AI takeover that ends in all technology being wiped out, many firms end up operating with outdated machinery and inefficient production methods. In the three-curve diagram, which curve is most directly influenced and in which direction does it shift? | Macroeconomics | 3.2 | 32 | 21.9% | 78.1% | 33.4 s |
| What happens to the economy if the government cuts payroll taxes on firms, reducing the cost of hiring workers? | Macroeconomics | 3.2 | 32 | 46.9% | 53.1% | 32.7 s |
| How is the economy affected when nominal wages rise significantly across the economy due to strong trade union bargaining? | Macroeconomics | 3.2 | 23 | 34.8% | 65.2% | 32.0 s |
| What happens to aggregate demand if the domestic currency depreciates sharply against major trading partners’ currencies? | Macroeconomics | 3.2 | 18 | 50.0% | 50.0% | 31.2 s |
| What is the short-run impact on the economy when the government launches a large infrastructure programme, increasing spending on roads, railways and public transport? | Macroeconomics | 3.2 | 28 | 67.9% | 32.1% | 35.0 s |
Most Correct Questions
| Question | Topic | Unit | Attempts | Correct | Wrong | Avg Time |
|---|---|---|---|---|---|---|
| In the short run, what is the effect on aggregate demand when central banks significantly lower interest rates, making it cheaper for firms to borrow and invest in new machinery? | Macroeconomics | 3.2 | 22 | 100.0% | 0.0% | 55.7 s |
| How is the economy impacted when there is a significant improvement in worker productivity due to automation? | Macroeconomics | 3.2 | 21 | 100.0% | 0.0% | 20.6 s |
| What is the effect on the economy when the central bank cuts interest rates significantly, making both consumer credit and firm borrowing cheaper? | Macroeconomics | 3.2 | 20 | 100.0% | 0.0% | 13.6 s |
| What happens to aggregate demand if the government raises income taxes on households, reducing their disposable income? | Macroeconomics | 3.2 | 20 | 100.0% | 0.0% | 11.4 s |
| How is the LRAS curve affected if institutions weaken over time, for example through rising corruption and weaker enforcement of property rights? | Macroeconomics | 3.2 | 19 | 100.0% | 0.0% | 14.1 s |
Most Time Spent Questions
| Question | Topic | Unit | Attempts | Correct | Wrong | Avg Time |
|---|---|---|---|---|---|---|
| In a single diagram for streaming subscriptions, show the effects of a major cost-saving AI recommendation system and negative media coverage that makes some users cancel their subscriptions. | Microeconomics | 2.2 | 15 | 46.7% | 53.3% | 1.5 min |
| A commercial bank receives an initial deposit of $1,000 and the required reserve ratio is 10%. Using the money multiplier formula, calculate how much new credit the banking system created. | macroeconomics | 3.3 | 5 | 40.0% | 60.0% | 1.3 min |
| Global coffee prices stay high for several years after a demand surge; in the long run, what happens to the market supply of coffee? | Microeconomics | 2.2 | 6 | 16.7% | 83.3% | 1.1 min |
| The government raises the indirect tax on sugary drinks. What happens to the market supply of sugary drinks? | Microeconomics | 2.2 | 6 | 100.0% | 0.0% | 1.0 min |
| Farmers expect the price of wheat to fall significantly in the near future. What is likely to happen to the current market supply of wheat? | Microeconomics | 2.2 | 6 | 83.3% | 16.7% | 57.3 s |
5. Conclusion
Next steps
Focus short practice sessions on Unit 3.2 SRAS vs LRAS shifts and on drawing combined diagrams step-by-step; use one timed diagram exercise and two short written explanations per topic this week.
Note: This weekly report is automatically generated and may contain mistakes. Always double-check key points before using them for revision.
This report is based on anonymized aggregate quiz activity for the week; no individual student data is shown.