Asian Review of Financial Research Vol.28 No.1 pp.1-36
Structural Change of Beta Asymmetry in the Korean Stock Market
Key Words : Capital Markets Liberalization,Asymmetry Beta,LTSR Model,Market Coupling,Industrial Analysis
This paper reports an overall regime shift in asymmetric beta upon liberalization of the Korean stock market. There are various researches for effects of market liberalization. Especially, the global financial crisis in recent triggers great controversy over the capital market liberalization and global financial integration. And after many emerging countries, even developed countries go through unexpected capital flow, such controversy is deepening. It leads for us to consider the liberalization of the Korean stock market discreetly. Previous studies mainly concentrate the impact to the foreign-exchange market and real economy or the effectiveness of foreign investment. However, the structural change of capital market itself has been ignored. We attempt to organize specific arguments and previous discussions upon economic impact of the liberalization. We verify the long-term beta features using the longest data before and after Korean capital market liberalization. And we also attempt to identify the industrial characteristics of asymmetric beta. Hence, our study can be considered as associative study of capital market liberalization issue and asymmetric beta issue. The empirical results are summarized as follows. First, over the sample period, we consistently observe the existence ofasymmetric beta under the diverse categories of bull market (bear market). Our finding is consistent with previous studies such that the investors recognize the upside gain and down loss differently. Second, the sensitivity of beta under a bull market has increased after the liberalization. However, we find only weak evidences of beta expansion in bear market. These results denote that the typical paradigm that the sensitivity to down loss is higher is maintained, however, the investors are more conscious about the upside after the liberalization. In other words, the investors actively start to reflect the upside signal after the liberalization. Third, we find an intensified co-movement of Korean capital market and the foreign capital markets, Additionally, the conditional beta by the foreign market's direction increases significantly. However, PND, the simplest criteria, shows the opposite results. It denotes that the investment strategy based on PND criteria may make an erroneous decision. Forth, the intensity of asymmetry beta varies in the cross-section of industrial sectors. Based on KSIC, we only observe asymmetric beta in ‘manufacturing', ‘construction', ‘financial and insurance business', and ‘professional and scientific service' sectors. Specially, in the majority of sectors, downward beta is higher than upside beta, however, the opposite result is derived in ‘financial and insurance business' sector. It denotes that ‘financial and insurance business' sector takes the leading role in increasing for the upside beta after the liberalization. Fifth, from the detailed analysis with industrial sub-sectors, we verify the significant differences among sub-sectors despite the significant upper-sectors. As a result, the capital market liberalization affects separate impacts and post changes by the industry sector. A practical implication suggests sector-based differentiation in portfolio management facing global market risks. We ask for careful attention to interpret our results. Korean capital market has experienced a considerable change by complex policies after the liberalization. Therefore, restricted interpretation such that our empirical findings are not derived only from the liberalization, but rather the liberalization becomes a turning point of the structural change and there is a possibility such that the discriminative impacts by industrial sectors after the liberalization is appropriate.