Cover image

MoE Money, MoE Problems? FinCast Bets Big on Foundation Models for Markets

TL;DR for operators FinCast is a finance-specific time-series foundation model that tries to do for market forecasting what large pretrained models did for language: absorb enough diverse data that new tasks require less bespoke engineering.1 The paper reports strong evidence on forecasting accuracy. In a zero-shot benchmark of 3,632 financial time series and more than 4.38 million scalar time points, FinCast beats general-purpose time-series foundation models on average, with roughly 20% lower MSE and 10% lower MAE. In supervised stock benchmarks, even the zero-shot version beats the listed supervised baselines; lightweight fine-tuning improves the gap further. ...

August 30, 2025 · 16 min · Zelina
Cover image

Curvature in the Jump: Geometrizing Financial Lévy Models

TL;DR for operators Jaehyung Choi’s paper does not offer a new trading strategy, volatility forecast, or backtest that makes the Sharpe ratio stand up and sing.1 Its contribution is more structural: it builds an information-geometric framework for Lévy processes, the family of stochastic processes often used when financial returns refuse to behave like polite Gaussian increments. ...

August 3, 2025 · 17 min · Zelina
Cover image

Noise-Canceling Finance: How the Information Bottleneck Tames Overfitting in Asset Pricing

TL;DR for operators Most quant teams already know the awkward truth: adding model capacity often makes the research backtest look smarter while making the deployed model less useful. The interesting part of Che Sun’s paper is not that it adds another neural network to asset pricing. We have enough of those. The useful move is more surgical: it asks the factor model to keep the information that helps explain returns and discard the information that merely helps memorise noisy firm characteristics.1 ...

August 1, 2025 · 16 min · Zelina
Cover image

Speed Bumps and Swells: Rethinking Optimal Trading with Stochastic Volatility

TL;DR for operators Execution desks already know that volatility matters. The useful question is less poetic: which volatility, on what time scale, and what should the trading algorithm actually do about it? The paper by Patrick Chan, Ronnie Sircar, and Iosif Zimbidis extends the Gârleanu-Pedersen optimal trading framework from constant volatility to predictable returns, temporary transaction costs, persistent price impact, and multiscale stochastic volatility.1 That combination matters because it puts the model closer to the daily problem of a trading desk: alpha is changing, risk is changing, and the desk’s own trades are also moving the price. Delightful. The market is not merely adversarial; it is participatory. ...

July 27, 2025 · 15 min · Zelina
Cover image

Signals & Sentiments: How GPT-2 and FinBERT Beat Buy-and-Hold on the S&P 500

TL;DR for operators A recent arXiv paper tests whether financial-news sentiment from GPT-2 and FinBERT can improve S&P 500 trading when combined with technical indicators and time-series models.1 The strongest reported strategy, GPT-2 sentiment on Dow Jones news combined with VW MACD, returns 5.77% over the May 10-August 7, 2024 test period. The buy-and-hold benchmark returns -0.696% over the same window. ...

July 20, 2025 · 15 min · Zelina
Cover image

Simulate First, Invest Later: How Diffusion Models Are Reinventing Portfolio Optimization

TL;DR for operators Portfolio teams do not lack optimisation formulas. They lack enough relevant future scenarios. That is the problem this paper attacks. The paper proposes a diffusion-based market simulator that learns from historical time-series data, then generates conditional future paths based on the current market state.1 Those generated paths become the training environment for a reinforcement-learning portfolio agent. In plain terms: instead of asking an RL policy to learn from a thin archive of market history, the system first builds a synthetic scenario engine and lets the policy practise there. Sensible. Also dangerous, if the simulator hallucinates a market that conveniently rewards your model. ...

July 20, 2025 · 16 min · Zelina