Tracking High-Frequency Trading Activity in China and Its Effects on Market Quality

Paper: arXiv 2610.33400

Authors: Li Guo, Frank Weikai Li, Ding Qi, Lijian Sun

Abstract

We develop a new order-level proxy for high-frequency trading (HFT) activity based on precise order placement and study its effects on market quality. With quotes updating multiple times per second, millisecond-level order-book access makes high-frequency traders more likely to submit active exact-match orders, defined as limit orders priced exactly at the prevailing best opposite-side quote. Using Shenzhen Stock Exchange data, we validate the proxy: active exact-match orders respond faster to quote updates, cancel more rapidly, concentrate when depth imbalance is favorable and spreads are narrow, and predict mid-quote returns from 100 milliseconds through ten minutes. A difference-in-differences design exploiting cross-channel variation in order dissemination latency at the market open shows that lower latency increases active exact-match shares. This variation yields plausibly causal evidence that latency-induced HFT raises short-horizon price variation, wide-spread incidence, and adverse-selection exposure, while realized spreads decline and pricing error falls modestly. Unlike developed markets, China’s T+1 constraint, absence of maker-taker rebates, and limits on rapid quote revision tilt speed advantages toward directional liquidity taking, highlighting how market design shapes the channel through which speed affects market quality.

Complexity vs Empirical Score

• Math Complexity: 6.0/10
• Empirical Rigor: 6.0/10 (capped from 8.0: no out-of-sample test; see penalty flags)
• Quadrant: Holy Grail — high math complexity, high empirical rigor

Why this score: The paper presents a novel empirical proxy for HFT activity and rigorously validates it using high-frequency data. The difference-in-differences design provides a strong causal identification strategy, contributing significantly to the understanding of HFT in a unique market setting.

Research Flowchart

  flowchart TD
    A[Research Goal: Track HFT in China and Effects on Market Quality] --> B{Develop New Order-Level HFT Proxy};
    B --> C[Data: Shenzhen Stock Exchange Order Book Data];
    C --> D{Validate HFT Proxy: Exact-Match Orders & Response to Quote Updates};
    D --> E{Causal Inference: Difference-in-Differences using Order Dissemination Latency};
    E --> F[Outcomes: HFT Raises Price Variation, Wide Spreads, Adverse Selection; Lowers Realized Spreads, Pricing Error];
    F --> G[Context: China's Market Design (T+1, No Maker-Taker) Favors Directional Liquidity Taking];