2026-W31
Strong grasp of AD shifts; confusion over quasi‑public goods and combined diagrams
This week students showed consistent strength with aggregate demand shifts (Unit 3.2) but struggled most with quasi‑public goods and multi‑shift diagram questions in Microeconomics (Units 2.9 and 2.2).
Published August 9, 2026
Total attempts
48
Average score
80.8%
Question accuracy
82.4%
Avg time per question
66.8s
1. Weekly Overview
Clear AD understanding, weaker concept classification and combined diagrams
Aggregate demand determinants were answered correctly by nearly all participants, while several microeconomics concept and diagram questions (quasi‑public goods, supply responses to wage changes, combined entry + willingness‑to‑pay shifts) had very low accuracy and/or long response times. Time patterns suggest careful thinking on some items but also persistent conceptual gaps.
Student takeaway: Prioritise revising definitions and examples for public goods/excludability, and practise drawing stepwise diagram shifts for combined supply and demand scenarios.
2. Key Patterns
Main Insights
Biggest weakness — classifying quasi‑public goods
The top incorrect item asked for an example of a quasi‑public good (Micro, Unit 2.9) and had 0% correct over multiple attempts, indicating confusion around excludability and rivalry distinctions.
Advice: Review the formal definitions of public, private, club (quasi‑public) and common goods; make a short table of examples and test yourself with quick classification questions.
Clear strength — aggregate demand determinants (Unit 3.2)
Several AD shift scenarios (changes in business expectations, trading partner incomes, household confidence, currency appreciation, payroll taxes) were answered correctly by all attempts, showing reliable understanding of AD movements.
Advice: Consolidate this strength by practising AD diagrams that include policy responses and short written explanations linking cause → curve shift → output/price effects.
Difficulty with combined-shift and diagram questions
Questions requiring multi-step diagram reasoning (market entry + reduced willingness to pay, supply responses to wage changes, three‑curve SRAS/LRAS effects) showed low accuracy and high time spent—students either hesitated or struggled to translate scenarios into the correct curve shifts.
Advice: When practising diagrams, state each causal step aloud (what changes, which curve shifts, direction, short-run vs long-run effect) and time yourself on short MCQs to reduce overlong thinking during exams.
3. Revision Plan
Priority Areas
Quasi‑public (club) goods, excludability vs rivalry · 2.9
0% correct on the representative classification question; core definitional confusion.
Action: Make a 1‑page table of examples, do 8–10 quick classification MCQs, and write one short exam‑style justification for each example.
Market supply & demand with entry and willingness‑to‑pay shifts · 2.2
Combined shift diagram question had 0% correct and longer response times.
Action: Practice 6 diagram problems that involve simultaneous demand and supply shifts; for each, annotate steps: cause → curve(s) affected → direction → net effect on price/quantity.
Three‑curve AD/AS (SRAS, LRAS, AD) shifts and causes · 3.2
Mixed accuracy and long times on SRAS/LRAS causation questions suggest uncertainty about which curve moves for supply‑side shocks.
Action: Work through 5 SRAS/LRAS scenario cards (technology, wages, resource shocks) and sketch short‑run vs long‑run diagrams with one‑line explanations.
Marginal analysis basics · 1.2
Low correct rate and high time on marginal analysis MCQ indicates shaky application.
Action: Do 10 short marginal benefit/cost problems and practice describing optimal decision points in one sentence.
4. Question Evidence
Featured Questions
Most Wrong Questions
| Question | Topic | Unit | Attempts | Correct | Wrong | Avg Time |
|---|---|---|---|---|---|---|
| Which of the following is an example of a quasi-public good? | Microeconomics | 2.9 | 6 | 0.0% | 100.0% | 11.0 s |
| If the government raises indirect taxes (such as VAT) on most goods and services, how is the economy affected? | Macroeconomics | 3.2 | 5 | 0.0% | 100.0% | 10.3 s |
| In a single diagram for IB Economics revision courses, show what happens when more EdTech firms enter the market while a new, very effective free online resource reduces students' willingness to pay for paid courses. | Microeconomics | 2.2 | 5 | 0.0% | 100.0% | 22.8 s |
| If the wage rate for factory workers increases significantly, what happens to the market supply of laptops? (Assume laptops are made in factories) | Microeconomics | 2.2 | 5 | 0.0% | 100.0% | 14.7 s |
| 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 | 9 | 44.4% | 55.6% | 32.1 s |
Most Correct Questions
| Question | Topic | Unit | Attempts | Correct | Wrong | Avg Time |
|---|---|---|---|---|---|---|
| How is aggregate demand affected if business expectations about future profits worsen sharply, leading firms to postpone or cancel investment projects? | Macroeconomics | 3.2 | 9 | 100.0% | 0.0% | 66.8 min |
| How is the economy affected when incomes in major trading partner countries rise, increasing their demand for this country’s exports? | Macroeconomics | 3.2 | 9 | 100.0% | 0.0% | 9.2 s |
| How is aggregate demand affected when households become more confident about the future and expect their incomes to rise? | Macroeconomics | 3.2 | 9 | 100.0% | 0.0% | 9.5 s |
| What happens if the domestic currency appreciates significantly, making imports cheaper and exports more expensive to foreigners? | Macroeconomics | 3.2 | 9 | 100.0% | 0.0% | 12.1 s |
| What happens to the economy if the government cuts payroll taxes on firms, reducing the cost of hiring workers? | Macroeconomics | 3.2 | 9 | 100.0% | 0.0% | 15.7 s |
Most Time Spent Questions
| Question | Topic | Unit | Attempts | Correct | Wrong | Avg Time |
|---|---|---|---|---|---|---|
| How is aggregate demand affected if business expectations about future profits worsen sharply, leading firms to postpone or cancel investment projects? | Macroeconomics | 3.2 | 9 | 100.0% | 0.0% | 66.8 min |
| Which of the following is NOT a traditional assumption of firm behavior? | Microeconomics | 2.4 | 3 | 66.7% | 33.3% | 51.6 s |
| Marginal analysis is used to explain which of the following? | Introduction to Economics | 1.2 | 3 | 33.3% | 66.7% | 32.2 s |
| 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 | 9 | 44.4% | 55.6% | 32.1 s |
| A new social media trend makes a particular brand of trainers very popular. As a result, more consumers want to buy them at every price. Using a demand and supply diagram, what happens in the market for these trainers? | Microeconomics | 2.1 | 5 | 100.0% | 0.0% | 26.1 s |
5. Conclusion
Next steps for efficient revision
Focus first on clarifying public vs private vs club goods and then practise combined diagram questions step by step; keep timed short MCQ sets to reduce hesitation in the exam.
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 and does not include any individual student data.