Quantitative Finance

EMAzing Trends: When One Moving Average Beats a Basket of Signals The latest research from Sebastien Valeyre delivers a surprise to the CTA world: a single exponential moving average (EMA) can match — or even beat — the performance of elaborate, multi-indicator trend-following systems. This conclusion comes from an empirical validation of a 2014 theoretical model by Grebenkov & Serror, which predicted the optimal Sharpe ratio for an EMA-based trend strategy given market autocorrelation and trend strength. Unlike the industry’s love affair with blending MACDs, crossovers, momentum mixes, and Bollinger Bands, the data suggest that simplicity wins. ...

Pricing American options has long been the Achilles’ heel of quantitative finance, particularly in high dimensions. Unlike European options, American-style derivatives introduce a free-boundary problem due to their early exercise feature, making analytical solutions elusive and most numerical methods inefficient beyond two or three assets. But a recent paper by Jasper Rou introduces a promising technique — the Time Deep Gradient Flow (TDGF) — that sidesteps several of these barriers with a fresh take on deep learning design, optimization, and sampling. ...

Classic finance assumes that the past doesn’t matter — only the present state of the market matters for decisions. But in a new paper from researchers at Imperial College and Oxford, a kernel-based framework for trading strategy design exposes how this assumption leads to suboptimal choices. Their insight: memory matters, and modern tools can finally make use of it. ...

In the age of Transformers and neural nets that write poetry, it’s tempting to assume deep learning dominates every corner of AI. But in quantitative investing, the roots tell a different story. A recent paper—QuantBench: Benchmarking AI Methods for Quantitative Investment1—delivers a grounded reminder: tree-based models still outperform deep learning (DL) methods across key financial prediction tasks. ...

When your AI believes too much, you pay the price. AI-driven quantitative trading is supposed to be smart—smarter than the market, even. But just like scientific AI systems that hallucinate new protein structures that don’t exist, trading models can conjure signals out of thin air. These errors aren’t just false positives—they’re corrosive hallucinations: misleading outputs that look plausible, alter real decisions, and resist detection until it’s too late. The Science of Hallucination Comes to Finance In a recent philosophical exploration of AI in science, Charles Rathkopf introduced the concept of corrosive hallucinations—a specific kind of model error that is both epistemically disruptive and resistant to anticipation1. These are not benign missteps. They’re illusions that change the course of reasoning, especially dangerous when embedded in high-stakes workflows. ...