A Study on Market Power in Futures Distribution

선물 유통시장에서 시장지배력에 관한 연구

Purpose - This paper aims to investigate a profit maximizing incentive of foreign traders in distributing the KOSPI 200 Futures. Such an incentive may induce unsophisticated retail traders to suffer loss from speculative trading. Since Korean government increased the entry barriers of the market to protect unsophisticated traders, the market size has been decreasing while the proportion of the contract held by foreign traders has been increasing. These on going changes make the market imperfectly competitive, where a profit maximization incentives of foreign traders are expected to grow. In this paper, we attempt to find any evidence of such behavior, thereby providing implications regarding market policy and market efficiency. Research design, data, and methodology - According to Kyle(1985), an informed trader exploits his/her monopoly power optimally in a dynamic context so that he/she makes positive profit, where he/she could conceal his/her trading utilizing noise trading as camouflage. We apply the KOSPI 200 Futures market to the Kyle's model: foreign traders who take into account the effect of his/her trading to maximize expected profits as an informed trader, retail investors as noise traders, and financial institutions as market makers. To find any evidence of monopolistic behavior, we test the variants of trading volume and price data of the KOSPI 200 Futures over the period of 2009 and 2017. Results - First, we find that the price of the KOSPI 200 Futures are more volatile than the price of underlying asset. Second, we find that monopolistic foreign trader's trading order flows are consistent with exploiting his/her monopoly power to maximize profit. Finally, we find that retail investors' trading order flows are inversely consistent with maximizing profit, that is, uninformed retail investors suffer loss continuously in speculative trading against informed traders. Conclusions - Our results show that the quantity of strategic order flows may have a large effect on the price, therefore, resulting the market inefficiency. The results also imply that, in implementing regulations, the depth of the market must be considered to maintain market liquidity, and suggesting interesting research topics regarding the market structure.