• Korean System Dynamics Review
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• v.8 no.2
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• pp.175-190
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• 2007

Stock market volatility largely depends on firms' value and growth opportunities. However, with the globalization of world economy, the effect of the synchronization in major countries is gaining its importance. Also, domestically, the business cycle and cash market of the country are additional factors needed to be considered. The main purpose of this research is to attest the application and usefulness of System Dynamics as a general stock market forecasting tool. Throughout this research, System Dynamics suggests a conceptual model for forecasting a KOSPI(Korea Composite Stock Price Index), taking the factors of the composite stock price indexes in traditional researches. In conclusion of this research, System Dynamics was proved to bean appropriate model for forecasting the volatility and direction of a stock market as a whole. With its timely adaptability, System Dynamic overcomes the limit of traditional statistic models.

• Communications for Statistical Applications and Methods
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• v.9 no.3
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• pp.577-594
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• 2002

For the estimation and test of long memory feature in volatilities of stock indices and individual companies semiparametric approach, Geweke and Porter-Hudak (1983), is employed. Empirical study supports the strong evidence of volatility persistence in Korean stock market. Most of indices and individual companies have the feature of long term dependence of volatility. Hence the short memory models are unable to explain the volatilities in Korean stock market.

• Asia-Pacific Journal of Business
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• v.14 no.1
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• pp.73-91
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• 2023

Purpose - The purpose of this study is to re-examine the disclosure effect of stock splits and long-term performance after stock splits using stock split data over the past 10 years, and infer the motivation (signal or opportunism) of stock splits. In addition, we focus on exploring the determinants of the short- and long-term market response to stock splits. Design/methodology/approach - We measure the short-term market response to a stock split and the long-term stock performance after the stock split announcement using the event study method. We analyze whether there is a difference in the long-term and short-term market response to a stock split according to various company characteristics through univariate analysis and regression analysis. Findings - In the case of the entire sample, a statistically significant positive excess return is observed on the stock split announcement date, and the excess return during the 24-month holding period after the stock split do not show a difference from zero. In particular, the difference between short-term and long-term returns on stock splits is larger in companies with a large stock split ratio, small companies, large growth potential, and companies with a combination of financial events after a stock split. Research implications or Originality - The results of this study suggest that at least the signal hypothesis for a stock split does not hold in the Korean stock market. On the other hand, it suggests that there is a possibility that a stock split can be abused by the manager's opportunistic motive, and that this opportunism can be discriminated depending on the size of the stock split, corporate characteristics, and financing plan.

• The Korean Journal of Applied Statistics
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• v.24 no.1
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• pp.103-114
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• 2011

Current series for testing stock market cointegrations tend to be restricted to analyzing the relations between stock market prices and may not be able to understand the whole picture of the variations in the stock market system. The nature of the variations in the stock prices, between the countries that experienced economic crisis and those did not, are different for a certain period of time, and accordingly excluding the potentially important variables in the stock market system causes statistical bias. This study considers domestic foreign exchange markets and financial markets in testing for the cointegrating relations of the stock prices in Korea and major investing countries. The results demonstrate the possibility of specification errors unless those markets are included in the statistical modeling process.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1998.10a
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• pp.228-231
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• 1998

Artificial Intelligence literatures have recognized that stock market is a highly unstructured and complex domain so that it is difficult to find knowledge that belongs to that domain. This paper demonstrates that the proposed QCOM can derive global knowledge about stock market on the basis of a set of local knowledge and express it as a digraph representation. In addition, inference mechanism using quantitative causal reasoning can describe the qualitative and quantitative effects of exogenous variables on stock market.

• Journal of Distribution Science
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• v.21 no.9
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• pp.103-114
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• 2023

Purpose: This paper aims to assess psychological heuristics' effectiveness on cumulative returns after significant stock price changes. Specifically, it compares availability and anchoring heuristics' empirical validity due to conflicting stock return predictions. Research Design, Data, and Methodology: This paper analyzes stock price changes of Korean distribution industry stocks in the KOSPI market from January 2004 to July 2022, where daily fluctuations exceed 10%. It evaluates availability heuristics using daily KOSPI index changes and tests anchoring heuristics using 52-week high and low stock prices as reference points. Results: As a result of the empirical analysis, stock price reversals did not consistently appear alongside changes in the daily KOSPI index. By contrast, stock price drifts consistently appeared around the 52-week highest stock price and 52-week lowest stock price. The result of the multiple regression analysis which controlled for both company-specific and event-specific variables supported the anchoring heuristics. Conclusions: For stocks related to the Korean distribution industry in the KOSPI market, the anchoring heuristics theory provides a consistent explanation for stock returns after large-scale stock price fluctuations that initially appear to be random movements.

• Journal of Distribution Science
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• v.21 no.12
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• pp.83-89
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• 2023

Purpose: Research on spin-off and treasury stock is necessary because the market has realized that this can be utilized for major shareholder private interest. Considering the unique characteristic of a spin-off and treasury stock in the Korean stock market, this study contributes to the literature by examining the effects on shareholder value in the Korean distribution industry. Research design, data, and methodology: The present study investigates literature, analyst reports, and news articles to examine the spin-off process and analyze how treasury stock magic happens. Results: Setting the exchange ratio favoring Spin-Co in the spin-off is the leading cause for reducing the minor shareholders' value. Moreover, treating treasury stock as an asset is also problematic, allowing the allocation of Spin-Co shares. This leads to an increase in the major shareholder controls of Spin-Co without any contribution from the major shareholders. Therefore, the exchange ratio should be calculated reasonably, and treasury stock from the stock repurchase should be treated as stock retirement. Conclusion: By analyzing the spin-off and how treasury stock magic occurs, this study provides recommendations to improve shareholder value. Moreover, it contributes to the maturation of the Korean capital market by promoting a discussion on the revision of spin-off and treasury stock.

• The Korean Journal of Financial Management
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• v.20 no.1
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• pp.61-92
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• 2003

As an extension of previous researches with the conclusion that the announcement of adopting stock options generates positive abnormal returns, this paper examined whether the abnormal return changes over time or varies depending on the number of stock options granted. Empirical analysis was made to find whether the announcement of stock option awards has the same response in the stock market from the early days when stock option plans had been introduced in the Korean stock market till today when it was widespread. Results indicate that the announcement effect had been on a gradual decline since 2000. In addition, it is found that if a company announces stock option awards several times, the abnormal return gradually declines in proportion of the number of stock options granted. This implies that as the stock option awards become widespread, the positive effect that the announcement of adopting stock options generates as news has been on a relatively steady decrease. In short, it leads to a conclusion that the more companies grant stock options, and the more stock options a company announces, the less impact it has on the increase in the firm's value.

• Korean Management Science Review
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• v.30 no.1
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• pp.43-58
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• 2013

Although analysis of charts, which used in stock trading by distinguishing standardized patterns in the movements of stock prices, is simple and easy to use, there can be problems stemming from specific patterns being distinguished as a result of the subjective perspectives of analysts. In accordance with such problems, through the method of template pattern matching, 4 trend reversal patterns were designed and the fitness of the patterns were quantitatively measured. In cases when a stock is purchased when the template pattern fitness value is within a certain range and held for at least 20-days, the average return ratio was analyzed to be higher-with the difference being statistically significant-than the average return ratio attained from trading a stock according to the same method per the Efficient Market Hypothesis. From the results of stock trades of 2 domestic corporations to which the values of the 4 patterns had been applied based on the 4 strategies, it was possible to ascertain differences in the strategy- and pattern-dependent return ratios. Through this study, along with presenting the exceptions for the Efficient Market Hypothesis in stock trading, the fitness level of quantitative chart patterns was measured and the theoretical basis for application of such fitness level was proposed.

• Journal of Korean Institute of Industrial Engineers
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• v.29 no.1
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• pp.14-20
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• 2003

The purpose of this paper is an attempt to analyze the dynamic relationship between KSE and KOSDAQ, two competing markets in Korean stock market, in the viewpoint of competition. Lotka-Volterra model, one of well-known competitive diffusion model, is adopted to represent the competitive situations of Korean stock market and it is estimated using daily empirical index data of KSE and KOSDAQ during 1997~2001. The results show that there existed a predator-prey relationship between two markets in which KSE acted as a predator right after the emergence of KOSDAQ. This interaction was altered to a symbiotic relationship and finally to the pure competition relationship. We also perform an equilibrium analysis of the estimated Lotka-Volterra equations and, as a result, it is found that there is a market index equilibrium point that would be stable in the latest relationship.