2026-W25
Strong grasp of elasticity basics, but supply elasticity and market demand show clear gaps
Class-level results show reliable understanding of PED fundamentals and policy, while interpreting supply curves (PES) and deriving market demand need focused revision.
Published June 28, 2026
Average score
80.2%
Question accuracy
80.3%
Total attempts
23
Avg question time
97.6 s
Top incorrect item
0% correct — 'flat supply curve' (PES)
1. Weekly Overview
Elasticity strengths with targeted weaknesses in supply elasticity and market demand
Students performed well on core elasticity definitions and policy (PED, Pigouvian tax, PES>1) with average score ~80%, but several medium-difficulty items about flat supply curves (PES) and deriving market demand had high wrong-rates and/or long completion times, indicating conceptual gaps.
Student takeaway: Focus next on interpreting supply-curve shapes (PES) and how individual demands aggregate into market demand.
2. Key Patterns
Main Insights
Misreading supply-curve slope and PES
The item about a flat supply curve (PES) had 0% correct across attempts, showing students often misinterpret what 'flat' implies for elasticity.
Advice: Revisit the definition of price elasticity of supply and practice identifying perfectly elastic vs inelastic supply from graphs (flat = perfectly elastic, PES → ∞).
Uncertainty around market demand aggregation and determinants
Questions on how to derive market demand from individual demand and on determinants of PED / YED showed elevated wrong-rates and, in one case, very long completion time, suggesting either conceptual hesitation or unclear application.
Advice: Practice summing individual horizontal quantities to form market demand and review standard PED determinants and income-elasticity categories (YED>1 = luxury).
Solid grasp of core elasticity definitions and basic policy
Several items on PED definition, what increases PED, PES>1 classification, and Pigouvian tax were answered correctly by all attempts, indicating reliable understanding of these fundamentals.
Advice: Keep consolidating by applying these definitions to brief applied examples (graphs and short calculations).
3. Revision Plan
Priority Areas
Price elasticity of supply (PES) · 2.6
0% correct on flat-supply question shows consistent misinterpretation of slope vs elasticity.
Action: Do 6 short graph questions: identify PES from shapes, compute PES basic examples, and write one-sentence explanations for 'perfectly elastic' and 'perfectly inelastic'.
Market demand and aggregation · 2.1
High wrong-rate and long response time on deriving market demand from individuals.
Action: Work through 4 problems summing individual demand schedules into market demand; sketch and label axes each time.
Determinants of PED and income elasticity (YED) · 2.5
Errors on YED classification and PED determinants indicate confusion over categories like 'luxury' vs 'necessity'.
Action: Create a one-page cheat-sheet of determinants and YED ranges, then complete 8 quick classification MCQs under a 15-minute timer.
Shifts vs movements along curves · 2.2
Some high time-on-task suggests careful thinking but potential uncertainty when distinguishing causes of movement vs shift.
Action: Do 5 example scenarios and mark whether each is a movement or a shift, explaining the non-price determinant if applicable.
4. Question Evidence
Featured Questions
Most Wrong Questions
| Question | Topic | Unit | Attempts | Correct | Wrong | Avg Time |
|---|---|---|---|---|---|---|
| If a supply curve is flat, what does this indicate about PES? | Microeconomics | 2.6 | 3 | 0.0% | 100.0% | 15.0 s |
| What does a perfectly elastic demand curve look like? | Microeconomics | 2.5 | 3 | 33.3% | 66.7% | 15.3 s |
| Which type of good has a YED greater than 1? | Microeconomics | 2.5 | 3 | 33.3% | 66.7% | 14.8 s |
Most Correct Questions
| Question | Topic | Unit | Attempts | Correct | Wrong | Avg Time |
|---|---|---|---|---|---|---|
| Which of the following increases the price elasticity of demand for a good? | Microeconomics | 2.5 | 4 | 100.0% | 0.0% | 1.4 min |
| What does a Pigouvian tax aim to achieve? | microeconomics | 2.8 | 4 | 100.0% | 0.0% | 3.7 s |
| What does price elasticity of demand (PED) measure? | Microeconomics | 2.5 | 3 | 100.0% | 0.0% | 9.7 s |
Most Time Spent Questions
| Question | Topic | Unit | Attempts | Correct | Wrong | Avg Time |
|---|---|---|---|---|---|---|
| As the time period considered becomes longer, the price elasticity of demand for most goods tends to: | Microeconomics | 2.5 | 3 | 100.0% | 0.0% | 100.3 min |
| How is market demand derived from individual demand? | Microeconomics | 2.1 | 3 | 33.3% | 66.7% | 1.6 min |
| Which of the following increases the price elasticity of demand for a good? | Microeconomics | 2.5 | 4 | 100.0% | 0.0% | 1.4 min |
5. Conclusion
Next steps
Target short, focused practice on interpreting supply-curve shapes and on summing individual demands into market demand; reinforce with quick timed quizzes and a one-page summary of elasticity determinants.
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 only and contains no identifiable student data.