IMC 2002
contestants 182 · problems 12 (6+6) · scale 0–20 · per-problem yesPer-problem difficulty
Day 1
Day 2
Difficulty vs discrimination
Each dot is one problem. X — how many solved it (scored ≥ 8 of 10); Y — discrimination, i.e. how well the problem told strong contestants from weak ones (score-vs-total correlation).
A good problem sits high and away from the edges. Bottom-left dots separated nobody — almost everyone failed them the same way.
Problem statistics
Same data as the Day 1 / Day 2 charts above. Add diploma cohorts to compare winners against the field.
| # | difficulty | all | disc | topics | ||||
|---|---|---|---|---|---|---|---|---|
| avg | solved | near-0 | ||||||
| Day 1 | ||||||||
| P1 | easy | 8.2 | 77% | 11% | 0.34 | geometrypolynomials | ||
| P2 | medium | 6.2 | 49% | 16% | 0.53 | functional equationsreal analysis | ||
| P3 | medium | 4.4 | 41% | 49% | 0.41 | combinatoricssequences & series | ||
| P4 | hard | 3.5 | 25% | 38% | 0.50 | real analysistopology & metric spaces | ||
| P5 | killer | 3.1 | 4% | 44% | 0.58 | real analysisset theory & logic | ||
| P6 | killer | 0.2 | 2% | 98% | 0.21 | linear algebrainequalities | ||
| Day 2 | ||||||||
| P7 | easy | 8.8 | 85% | 5% | 0.31 | linear algebra | ||
| P8 | easy | 8.0 | 76% | 14% | 0.47 | combinatorics | ||
| P9 | easy | 5.6 | 51% | 38% | 0.48 | sequences & seriesnumber theory | ||
| P10 | very hard | 2.0 | 7% | 66% | 0.59 | geometryinequalities | ||
| P11 | killer | 1.9 | 4% | 20% | 0.36 | linear algebra | ||
| P12 | killer | 0.1 | 0% | 99% | 0.16 | real analysisinequalities | ||
A diploma-cohort cell needs at least 5 scores, else it shows “—”. How these statistics are computed →