LiveTradeBench: Seeking Real-World Alpha with Large Language Models
Authors: name: Haofei Yu, name: Fenghai Li, name: Jiaxuan You

Large language models (LLMs) achieve strong performance across
benchmarks--from knowledge quizzes and math reasoning to web-agent tasks--but
these tests occur in static settings, lacking real dynamics and uncertainty.
Consequently, they evaluate isolated reasoning or problem-solving rather than
decision-making under uncertainty. To address this, we introduce
LiveTradeBench, a live trading environment for evaluating LLM agents in
realistic and evolving markets. LiveTradeBench follows three design principles:
(i) Live data streaming of market prices and news, eliminating dependence on
offline backtesting and preventing information leakage while capturing
real-time uncertainty; (ii) a portfolio-management abstraction that extends
control from single-asset actions to multi-asset allocation, integrating risk
management and cross-asset reasoning; and (iii) multi-market evaluation across
structurally distinct environments--U.S. stocks and Polymarket prediction
markets--differing in volatility, liquidity, and information flow. At each
step, an agent observes prices, news, and its portfolio, then outputs
percentage allocations that balance risk and return. Using LiveTradeBench, we
run 50-day live evaluations of 21 LLMs across families. Results show that (1)
high LMArena scores do not imply superior trading outcomes; (2) models display
distinct portfolio styles reflecting risk appetite and reasoning dynamics; and
(3) some LLMs effectively leverage live signals to adapt decisions. These
findings expose a gap between static evaluation and real-world competence,
motivating benchmarks that test sequential decision making and consistency
under live uncertainty.