“…Bakshi et al (2000), Lin et al (2011), andWang, Huang, andKuo (2014) use intraday samples that cover only 6 months (March to August 1994, July to December 2006, and January to June 2009, respectively). 4 Previous studies on Korea's derivatives markets explain the top-tier position and significance of the KOSPI 200 options market, illustrating how option products can be used (Guo, Han, & Ryu, 2013;Kim & Ryu, 2015b;Lee, Kang, & Ryu, 2015;Lee & Ryu, 2014;Ryu, Kang, & Suh, 2015). Sim et al (2016) examine KOSPI 200 options data covering 2 years (2010-2011) and ignore recent market reforms (e.g., changes in option multipliers, regulation of speculators, and significantly increased requirements for the size of individual margin accounts), which have changed the trading environment and the composition of participating investors, possibly affecting the violation rate.…”