Bellwether Trades: Characteristics of Trades influential in Predicting Future Price Movements in Markets
Tejas Ramdas, Martin T. Wells
TL;DR
This paper addresses which trades carry information that predicts future price movements in financial markets. It develops an AutoML–optimized CNN predictor that operates on grid-structured trading windows and then derives per-trade influence scores via a first-order Taylor expansion of the predictor, $f(\cdot;\theta)$. A regression model then relates these influence scores to trade attributes (size, venue, time, year) and their interactions, revealing a long-tail distribution of predictive power and systematic differences across assets and venues. The framework is adaptable to varying window sizes and asset classes and provides a robust template for downstream inference in finance without relying on explicit microstructure models.
Abstract
In this study, we leverage powerful non-linear machine learning methods to identify the characteristics of trades that contain valuable information. First, we demonstrate the effectiveness of our optimized neural network predictor in accurately predicting future market movements. Then, we utilize the information from this successful neural network predictor to pinpoint the individual trades within each data point (trading window) that had the most impact on the optimized neural network's prediction of future price movements. This approach helps us uncover important insights about the heterogeneity in information content provided by trades of different sizes, venues, trading contexts, and over time.
