Susquehanna (SIG) Quant OA keeps the mental math + probability + Trading Combine triad in 2026. This playbook is built from oavoservice student debriefs and lays out the patterns, cadence, and pass thresholds for each segment.
1. SIG Quant OA structure
| Segment | Items / Time | Format |
|---|---|---|
| 90-second math | ~50 items / 8 min total | mental math + light logic |
| Probability / combinatorics | 10–15 / 30 min | multiple choice |
| Trading Combine | 30 min simulator | quoting / market making |
The 90-second segment is a speed gate (8–10 items per block); probability is an accuracy gate; Trading Combine is a strategy gate. Three independent scores.
2. 90-second math: speed gate
The format is + - × ÷ with simple percentages, e.g.:
(17 × 24) - (45 × 11) = ?47% of 320 = ?0.875 + 1/8 = ?(fraction–decimal conversion)
SIG scoring: a wrong answer costs more than no answer. Only attempt the ones you're 100% sure of, let the rest expire. Empirical pass: ~6–7 of 8 per block at the ~60th percentile.
Drills
- 2-digit × 2-digit mental math: 50/day × 4 weeks.
- Fraction ↔ decimal: 1/8, 1/16, 1/32, 3/8, 5/8 should be sub-1-second reflexes.
- % ↔ fraction: burn 12.5% = 1/8 and 6.25% = 1/16 into muscle memory.
3. Probability / combinatorics: accuracy gate
| Theme | Frequency | Tip |
|---|---|---|
| Conditional probability | high | Bayes / contingency table |
| Expectation / variance | high | linearity of expectation |
| Sampling / without replacement | high | hypergeometric |
| Light combinatorics | mid | inclusion-exclusion / stars-and-bars |
| Markov chains | mid | one-step transition matrix |
Recall: poker suits
Draw 5 cards from a 52-card deck without replacement. Probability of at least one heart and at least one spade?
Inclusion-exclusion: P(no hearts) + P(no spades) - P(neither) = 2·C(39,5)/C(52,5) - C(26,5)/C(52,5). Answer ≈ 0.738.
Recall: trading expectation
A stock at 100 goes up 5% with probability 0.55 and down 5% with 0.45 each day. Expected price after 5 days?
Daily expected multiplier: 0.55 × 1.05 + 0.45 × 0.95 = 1.005. 5-day expectation: 100 × 1.005^5 ≈ 102.53. Trap: don't add 5 days linearly; compound.
4. Trading Combine: strategy gate
This segment distinguishes SIG from other quant shops. The simulator gives a simplified market-making setting:
- A "true price" hint distribution
- You post bid / ask quotes
- 100 rounds of fills + score
Scoring breakdown
| Dimension | Weight | Notes |
|---|---|---|
| PnL | 40% | total profit |
| Quote spread | 30% | too wide → no fills, too tight → losses |
| Inventory management | 20% | rebalance when net position drifts |
| Information usage | 10% | update quotes off the hint |
Practical strategy
- Observe 5 rounds before getting bold: wide spread early to probe true price.
- Inventory balance: if net exposure > 10 lots, skew quotes to flatten.
- Use hints: hint says "true price is high" → shift both bid and ask up 1–2 ticks.
- No heroics at the end: in the last 10 rounds, prefer wide spread to avoid large losses.
oavoservice provides mental math drilling + probability bank + Trading Combine 1:1 mocks.
5. Threshold (22 samples)
[pass] ████████ 35%
[math cut] ██████ 27%
[prob cut] ██████ 27%
[combine cut] ███ 14%
~35% pass overall. Math + probability cut more than half. Combine has a higher pass rate due to a gentler curve.
6. 4-week prep cadence
| Week | Focus |
|---|---|
| W1 | 50 mental-math problems daily + fraction-decimal table |
| W2 | 100 probability problems: conditional, expectation, combinatorics |
| W3 | Trading Combine sim × 5 + strategy review |
| W4 | Full back-to-back simulation + loss diagnostics |
7. Scoring rubric (from student debriefs)
| Dimension | Weight | What recruiters track |
|---|---|---|
| Speed | 30% | answers per 90s block |
| Accuracy | 30% | probability hit rate |
| Strategy | 25% | Combine PnL + spread |
| Risk awareness | 15% | inventory control / late-game caution |
oavoservice runs SIG Quant OA coverage with mental math plans, probability deep dives, Combine strategy, and 1:1 review — end-to-end from OA to final.
FAQ
Retake on the SIG OA?
12-month cooldown. Switching track (Quant Trader → Quant Research) can reset.
What Combine score do I need?
Empirically the bar is ~60th percentile. PnL doesn't need to be huge, but spread must not be too wide.
Is coding required?
Quant Trader Intern: not really. Quant Research / Quant Dev: Python / C++ basics required.
What if the 90-second timer runs out?
Unanswered = 0; wrong = -1. Conservative answering is optimal.
What's next after passing?
Usually a recruiter call within 1–2 weeks, then onsite SuperDay (~6 rounds).
Preparing for the 2026 SIG Susquehanna Quant OA?
oavoservice has tracked SIG Quant OA for over three years, covering math / probability / Trading Combine. Services include mental math plans, probability bank, Combine strategy, and 1:1 review.
👉 Add WeChat: Coding0201, grab the latest SIG OA pack and prep plan.
Contact
Email: [email protected]
Telegram: @OAVOProxy