The promotion of financial stability is the mission of central banks and market authorities. This mission is more difficult to accomplish when trading activity is associated with financial instability in the form of intraday price jumps. While the literature has widely shown that exogenous news releases trigger these jumps, very little is known about the consequences of endogenous technical trading on market instability. Using high-frequency 5-min data on 460 NASDAQ stocks from February to September 2017, we provide new evidence that sharp price movements during the day are also triggered by technical trading around special market configurations. When technical trading activity dominates, intraday price jumps are detected more frequently, and their direction becomes significantly predictable, particularly in small caps and in the energy sector. Our results support the view that the explanations for intraday market instability are not limited to news releases.

促进金融稳定是中央银行和市场主管部门的使命。当交易活动与金融不稳定以盘中价格上涨的形式相关时，这项任务就更难完成。虽然文献广泛表明外生新闻发布会触发这些跳跃，但对内生技术交易对市场不稳定的后果知之甚少。使用 2017 年 2 月至 9 月 460 只纳斯达克股票的高频 5 分钟数据，我们提供了新的证据，证明白天的剧烈价格波动也是由围绕特殊市场配置的技术交易触发的。当技术交易活动占主导地位时，会更频繁地检测到盘中价格上涨，并且它们的方向变得非常可预测，尤其是在小盘股和能源领域。