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This paper examines the role of illiquidity and duration factor in understanding the momentum profit in the Korean stock market. We find that the foreigner/institutional illiquidity factor explains the momentum effect. In addition, this paper finds that duration factor defined as the difference in returns of short-duration and long-duration stocks captures well the momentum profits. That is, a two-factor model with the market and duration factor performs much better than competing asset pricing models in explaining the momentum effect. Finally, when controlling for the duration factor, the explanatory power of the foreign/institutional illiquidity factor on the momentum profits disappears. In sum, our empirical finding indicates that the duration factor is the most important ingredient in understanding the momentum effect in the Korean stock market.

The purpose of this paper is to empirically analyze the effect of the increasing connectedness among financial institutions in the Korean financial market, as it affects the market microstructure in the stock market. Thus this work, first, analyzes the trend and characteristics of connectedness in the Korean financial sector. This work then demonstrates the impacts of connectedness on volatility and price discovery in the stock market.

The entire Korean financial sector is analyzed from January 1990 to July 2015, including the periods of the 1997 Asian crisis and the 2007/2008 global financial crisis. This paper quantifies the connectedness between financial institutions using network methodology. Densely connectedness specifically refers to the cases in which a node experiences strong-lagged return spillover from and/or to itself.

Connectedness is established as an important determinant of stock price discovery. This paper illustrates that connectedness increases on significant economic events such as the 1997 Asian crisis and the 2007/2008 global financial crisis. Furthermore, this paper demonstrates that the more densely connected a particular financial institution, the more volatile the stock price and the less accurate the stock price quality.

Understanding the financial system from a network perspective has been on the rise after the 2007/2008 global financial crisis. This work helps regulators and policy makers understand the full implications of introducing new policies that can more closely connect financial institutions.

This paper precisely captures financial institutions’ connectedness by including all types of financial institutions at the micro level. Additionally, this paper links connectedness to market microstructure in the stock market.

The purpose of this study is to examine how the volatility interruption (VI) mechanisms affect idiosyncratic volatilities in Korean stock markets.

Collecting the South Korea Stock Market (KOSPI) data from June 15, 2015 to March 31, 2019, we collect each residual,  εi,t, from three different estimated models: capital asset pricing model (CAPM), FF3 and FF5. To estimate the conditional idiosyncratic volatility, the authors employ two conditional time-varying measurements: GARCH and TGARCH.

The results show that the conditional idiosyncratic volatility increases when stock prices reach the upper and lower static limits, indicating the implementation of adopting static VI mechanism neither stabilize market conditions nor reduce excess volatility along with the existence of price limits.

Although market regulators and policymakers improve market conditions with the advanced VI mechanism, the empirical results show the adverse effect of the mechanism. Not allowing investors to earn above average returns without accepting above average risks makes Korean stock markets inefficient along with advanced VI mechanisms.

This paper analyzes how three major industrial stock indices related to South Korean real estate industries are affected by the exogenous shock of the measures taken to control COVID-19, coupled with investor sentiment, which has global impacts.

The paper uses daily stock market indices on three major stock price indices: construction industry sector index, real estate operating company (REOC) industry index and the real estate investment trust (REIT) industry index of the Korea Stock Exchange (KRX), from January 8, 2020, when the World Health Organization (WHO) began to issue official indicators regarding COVID-19, to March 27, 2020, the last trading day of the week during which the South Korean government's stock market stabilisation fund was launched.

Results indicate the REIT sector's stock rate of return to be relatively less sensitive to impacts of COVID-19 compared to those of the two other indices. Impulse response analysis also shows similar results. Impulse response estimations indicate that earlier information of REITs has prominent significance in explaining changes in the time series process itself. Similar to findings of prior studies that have been conducted with long-term perspectives, results of our short-term study indicate that the medium-risk, medium-return characteristic of the real estate industry has significance even in short-term perspectives.

REITs can be an investment vehicle that provides strong benefits of diversified investment for mutual fund investment managers even in the case of short-term exogenous market disruptions.

The analysis run in the empirical exercise is the first to consider the sensibility between international stock exchanges to the effects of measures taken to control COVID-19 impact.

This paper aims to provide new perspectives on the integration of East Asian stock markets and the dynamic volatility transmission to the Bitcoin market utilising daily data from 2014 to 2020.

The authors undertake comprehensive analyses of the dependency dynamics, systemic risk and volatility spillover between major East Asian stock and Bitcoin markets. The authors employ a vine-copula-CoVaR framework and a VAR-BEKK-GARCH method with a Wald test.

(a) With exception of KS11 and N225; HSI and SSE; HSI and KS11, which have moderate dependence, dependencies among other markets are low. In terms of tail risk, the upper tail risk is more significant in capturing strong common variation. (b) Two-way and asymmetric risk spillover effects exist in all markets. The Hong Kong and Japanese stock markets have significant risk spillovers to other markets, and quite notably, the Chinese stock market is the largest recipient of systemic risk. However, the authors observe a more significant risk spillover from the Chinese stock market to the Bitcoin market. (c) The VAR-BEKK-GARCH results confirm that the Korean market is a significant emitter of volatility spillovers. The Bitcoin market does provide diversification benefits. Interestingly, the Chinese stock market has an intriguing relationship with Bitcoin. (d) An increase in spillovers in East Asia boosts spillovers to Bitcoin, but there is no intuitive effect of Bitcoin spillovers on East Asian spillovers.

For the first time, the authors examine the dynamic linkage between Bitcoin and the major East Asian stock markets.

The purpose of this paper is to examine the changes in the price impact of trades in the major Korean stock market following the introduction of disclosure to all traders of the top five brokers on the buy-side and the top five brokers on the sell-side of trades in real time for each stock in the KOSDAQ market.

The paper uses several alternative metrics for the price impact of trades. The study applies estimation methodology that accounts for the potential endogeneity of other market quality proxies, which are used as control variables in price impact regressions, by utilizing two-stage-least-square methods with fixed effect specification.

This study finds that the permanent price impact (information effect) of both buyer- and seller-initiated trades increases, which indicates that information is disseminated quicker in a transparent market. Uninformed trades have a larger permanent price impact than informed trades on both the buy and sell sides. The liquidity price effects are found to be mixed for buys and sells.

The study supports the current policy of the Korean Exchange to publicly display the five most active broker IDs on both the buy and sell sides, as it attracts both informed and liquidity traders, leading to faster price discovery in a more transparent market. However, a future study which analyzes the change in the market quality in both local markets would provide a complete picture of the effects of the policy.

Earlier studies documenting the effect of broker ID disclosure on market quality used effective spreads, market depth or order book imbalance as market quality measures. This study contributes to the existing literature by examining the changes in direct measures of the private information effect and liquidity effect of trades in a stock market – the Korean Stock Exchange – when the other part of the exchange (the KOSDAQ stock market) shifts to public broker ID transparency at the same transparency level.

This study aims to focus on the profitability of momentum trading in the Korean stock market. More specifically, it aims to conduct an examination of the relationship between momentum returns and idiosyncratic volatility (IVol) to determine whether momentum profits can be explained by IVol.

Portfolios are formed based on their past performance and examine the momentum, or contrarian returns, as the difference between winning and losing portfolios. To confirm that the momentum strategy provides excess returns, the relationship between momentum returns and IVol is studied. The Fama and French three‐factor model is also examined to see whether systematic risk affects momentum profits. Firm size, stock price, and turnover are controlled to determine robustness. Finally, a time‐series relationship between aggregate IVol and momentum profits is investigated.

The paper illustrates that excess returns are obtained from a momentum strategy, not a contrarian strategy, in the Korean stock market. Momentum returns are higher among high IVol stocks, especially high IVol winners. Examining the Fama and French three‐factor model, it is found that momentum returns cannot be explained by systematic risk. The findings are robust after controlling for factors such as firm size, book‐to‐market ratio, and turnover. The paper confirms the effect of IVol on momentum returns by illustrating that a time‐series relationship between momentum returns and aggregate IVol is positive.

This paper is among the first, to the authors' knowledge, to examine the relationship between momentum profits and IVol in the Korean stock market, one of the mature financial markets. The findings in this study can be applied to better understand the sources of gains from the momentum strategy in international stock markets.

In this study, we investigate what drives the MAX effect in the South Korean stock market. We find that the MAX effect is significant only for overpriced stocks categorized by the composite mispricing index. Our results suggest that investors' demand for the lottery and the arbitrage risk effect of MAX may overlap and negate each other. Furthermore, MAX itself has independent information apart from idiosyncratic volatility (IVOL), which assures that the high positive correlation between IVOL and MAX does not directly cause our empirical findings. Finally, by analyzing the direct trading behavior of investors, our results suggest that investors' buying pressure for lottery-like stocks is concentrated among overpriced stocks.

The authors estimate systemic risk in the Korean economy using the econometric measures of commonality and connectedness applied to stock returns. To assess potential systemic risk concerns arising from the high concentration of the economy in large business groups and a few export-oriented sectors, the authors perform three levels of estimation using individual stocks, business groups, and industry returns. The results show that the measures perform well over the study’s sample period by indicating heightened levels of commonality and interconnectedness during crisis periods. In out-of-sample tests, the measures can predict future losses in the stock market during the crises. The authors also provide the recent readings of their measures at the market, chaebol, and industry levels. Although the measures indicate systemic risk is not a major concern in Korea, as they tend to be at the lowest level since 1998, there is an increasing trend in commonality and connectedness since 2017. Samsung and SK exhibit increasing degrees of commonality and connectedness, perhaps because of their heavy dependence on a few major member firms. Commonality in the finance industry has not subsided since the financial crisis, suggesting that systemic risk is still a concern in the banking sector.

The authors aim to understand the driving forces behind the idiosyncratic volatility puzzle in the Korean stock market. The authors study the Korean stock market because previous works report a strong idiosyncratic volatility puzzle in Korea, and the market for the exchange-traded funds (ETFs) including low volatility ETFs has experienced drastic growth in Korea.

Using common stocks listed either on KOSPI or KOSDAQ over the period 1997–2016, the authors estimate idiosyncratic volatility using the Fama–French three-factor model. In addition, based on prior literature, the authors use turnover as a proxy for overvaluation. The authors then study the role of turnover in understanding the idiosyncratic volatility puzzle in Korea.

The authors find that turnover is highly associated with idiosyncratic volatility. Turnover is extremely large among firms with high idiosyncratic volatility and the puzzle disappears after we control for turnover, meaning that turnover subsumes the explanatory power of idiosyncratic volatility for equity returns. The authors also find underperformance of stocks with high turnover and high idiosyncratic volatility exclusively during earnings announcement periods. Overall, our finding implies that the puzzle arises since high idiosyncratic volatility stocks due to high turnover are overvalued and experience correction afterwards.

Literature has suggested explanations based on lottery preferences of investors and market frictions behind the idiosyncratic volatility puzzle. What makes our study distinct from previous work is that we find the role of turnover in understanding the idiosyncratic volatility puzzle using turnover measure as a proxy for overvaluation in the Korean stock market.