Market fairness and efficiency: Evidence from the Tokyo Stock Exchange
研究了东京证券交易所2015年实施的Arrowhead Renewal改进对市场公平和效率的影响，发现公平性大幅提升（收盘操纵事件减少61.19%），效率改善较小（有效价差缩小6.45%），对低最小报价单位和高市值股票影响最大。
In 2015 the Tokyo Stock Exchange (TSE) implemented Arrowhead Renewal improvements (ARI) that reduced latency from about one millisecond to less than 0.5 ms. Simultaneously, the ARI introduced new risk management functions to improve market fairness by reducing manipulative trading strategies. We find a dramatic improvement in market fairness as proxied by marking-the-close incidents, which declined by 61.19%. We find a much smaller improvement in market efficiency. Specifically, there was a reduction in the effective (quoted) spread of 6.45% (5.79%). The most dramatic improvement in market quality (fairness and efficiency) was for low-tick-size and high-market-capitalization stocks.