“…Credit Suisse (2012) finds that long-term volatility in recent years remained within historical norms, while short-term volatility declined, concluding that markets are "not worse" for the presence of HFT. Hagströmer, Nordén and Zhang (2014) note that the "aggressiveness" of orders submitted varies by HFT firm and by market situations, "adhere strongly to the tradeoff between waiting cost and the cost of immediate execution," and that HFT firms react less strongly to recent volatility than do non-HFT participants. Moreover, Lepone (2011), Hagströmer andNordén (2013), and Bank for International Settlements (2011) provide global evidence that HFT firms have been active during both high-and low-volatility conditions, and that high-frequency traders have often been the primary providers of liquidity in periods of high uncertainty, as well as mitigating intraday pricing volatility.…”