QSYS v1.0

Paper Explorer

Interactive reproductions of the key findings from the portfolio sizing literature

Quant StudioPaper Explorer

RELATED TOOLS

1. Optimal Portfolio Size

Vanderveken, Lassance & Vrins (2024) — Optimal Portfolio Size under Parameter Uncertainty

Key finding: Optimal N ≈ N_sample / 2 — more assets ≠ better, estimation risk dominates signal

2. Optimal Granularity

Branger, Lucivjanska & Weissensteiner (2019) — Optimal Granularity for Portfolio Choice

Key finding: Group assets into 5-10 equally-weighted clusters — 30-50% reduction in estimation error vs full MV

3. Risk Budgeting Portfolios

da Costa, Pesenti & Targino (2023) — Risk Budgeting Portfolios

Key finding: Equal risk contribution reduces concentration vs equal-weight by ~40% — no expected returns needed

4. LTCM Sizing Failure

US Treasury (1999) — Lessons from the LTCM Failure

Key finding: 43× leverage + >5% concentration + correlation regime shift = terminal risk

5. ML-Based Risk Allocation

Nature Scientific Reports (2025) — LSTM Vol Forecaster + Differential Risk Budgeting

Key finding: Sharpe 1.38 (55% over risk parity) with LSTM vol forecaster + regime-switching

6. Varying Investor Abilities

James & Menzies (2023) — Portfolio Diversification with Varying Investor Abilities

Key finding: Skilled investors concentrate (N=5-10); unskilled diversify (N=20+)