• Journal of the Korean Operations Research and Management Science Society
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• v.29 no.2
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• pp.45-57
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• 2004

The purpose of this paper is studying the valuation of option prices in Incomplete markets. A market is said to be incomplete if the given traded assets are insufficient to hedge a contingent claim. This situation occurs, for example, when the underlying stock process follows jump-diffusion processes. Due to the jump part, it is impossible to construct a hedging portfolio with stocks and riskless assets. Contrary to the case of a complete market in which only one equivalent martingale measure exists, there are infinite numbers of equivalent martingale measures in an incomplete market. Our research here is focusing on risk minimizing hedging strategy and its associated minimal martingale measure under the jump-diffusion processes. Based on this risk minimizing hedging strategy, we characterize the dynamics of a risky asset and derive the valuation formula for an option price. The main contribution of this paper is to obtain an analytical formula for a European option price under the jump-diffusion processes using the minimal martingale measure.

• The Journal of Industrial Distribution & Business
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• v.10 no.6
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• pp.51-58
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• 2019

Purpose - Prior studies reported that the opacity of information caused stock price crash. If managers fail to disclose unfavorable information about the firm over a long period of time, the stock price is overvalued compared to its original value. If the accumulated information reaches a critical point and spreads quickly to the market, the stock price plunges. Information management by management's disclosure policy can cause information uncertainty, which will lead to a plunge in stock prices in the future. Thus, this study aims at examining the impact of disclosure quality on crash risk by focusing on the unfaithful disclosure firms. Research design, data, and methodology - This study covers firms listed on KOSPI and KOSDAQ from 2004 to 2013. Firms excluded from the sample are non-December firms, capital-eroding firms, and financial firms. The financial data used in the research was extracted from the KIS-Value and TS2000 database. Unfaithful disclosure firm designation data was collected from the Korea Exchange's electronic disclosure system (kind.krx.co.kr). Stock crash is measured as a dummy variable that equals one if a firm experiences at least one crash week over the fiscal year, and zero otherwise. Results - Empirical results as to the relation between unfaithful disclosure corporation designation and stock price crashes are as follows: There was a significant positive association between unfaithful disclosure corporation designation and stock price crash. This result supports the hypothesis that firms that have previously exhibited unfaithful disclosure behavior are more likely to suffer stock price plunges due to information asymmetry. Second, stock price crashes due to unfaithful disclosures are more likely to occur in Chaebol firms. Conclusions - While previous studies used estimates as a proxy for information opacity, this study used an objective measure such as unfaithful disclosure corporation designation. The designation by Korea Exchange is an objective evidence that the firm attempted to conceal and distort information in the previous year. The results of this study suggest that capital market investors need to investigate firms' disclosure behaviors.

• Journal of the Korean Statistical Society
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• v.35 no.2
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• pp.193-199
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• 2006

We consider a zero coupon bond that is at the risk of multitype multiple defaults. Assuming defaults occur according to k Cox processes, we find a price process for zero coupon bonds. To derive this process we follow the Lando (1998)'s method which uses conditional expectations instead of the traditional methods.

• Korean Journal of Construction Engineering and Management
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• v.11 no.1
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• pp.113-121
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• 2010

Since the cut-down of the purchasing price of the feed in tariff(FIT) in 2008, the numbers of photovoltaic projects get decreased, contrary to investment expansion policy of government on renewable energy. The root cause of the decrease is the irrationality of the current purchasing price structure of FIT as well as the adversity of fund raising due to the global financial crisis. This study proposes the FIT calculating model (Cost & Benefit Risk Based Purchase Price Process : CBRP3) reflecting the fluctuation of cost and benefit risks. The first step is to establish the photovoltaic generation alternatives, and to calculate each distribution data of the investment and the power generation quantity. The FIT for each alternative is, then, assessed through simulations. Finally the proposed FIT scheme is compared to the present FIT scheme and future study subjects are derived.

• The Journal of Industrial Distribution & Business
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• v.12 no.3
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• pp.43-49
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• 2021

Purpose: This study attempted to examine the risk of stock price plunge according to the firm's management strategy. Prospector firms value innovation and have high uncertainties due to rapid growth. There is a possibility of lowering the quality of financial reporting in order to meet market expectations while withstanding the uncertainty of the results. In addition, managers of prospector firms enter into compensation contracts based on stock prices, thus creating an incentive to withhold negative information disclosure to the market. Prospector firms' information opacity and delays in disclosure of negative information are likely to cause a sharp decline in share prices in the future. Research design, data and methodology: This study performed logistic analysis of KOSPI listed firms from 2014 to 2017. The independent variable is the strategic index, and is calculated by considering the six characteristics (R&D investment, efficiency, growth potential, marketing, organizational stability, capital intensity) of the firm. The higher the total score, the more it is a firm that takes a prospector strategy, and the lower the total score, the more it is a firm that pursues a defender strategy. In the case of the dependent variable, a value of 1 was assigned when there was a week that experienced a sharp decline in stock prices, and 0 when it was not. Results: It was found that the more firms adopting the prospector strategy, the higher the risk of a sharp decline in the stock price. This is interpreted as the reason that firms pursuing a prospector strategy do not disclose negative information by being conscious of market investors while carrying out venture projects. In other words, compensation contracts based on uncertainty in the outcome of prospector firms and stock prices increase the opacity of information and are likely to cause a sharp decline in share prices. Conclusions: This study's analysis of the impact of management strategy on the stock price plunge suggests that investors need to consider the strategy that firms take in allocating resources. Firms need to be cautious in examining the impact of a particular strategy on the capital markets and implementing that strategy.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.17 no.1
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• pp.29-43
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• 2022

This study measures the realized rate of return of venture capital(VC) fund at the level of investment agreement(as opposed to fund level returns reported by most of the relevant studies). It also measures the stock price return of the VC's portfolio firms (unlisted start-ups) at firm level(as opposed to fund returns) and its variance for the first time using unique data of the VC funds held by the Korean Venture Capital Association. Results of the analysis confirm that VC fund returns exceed individual stock price returns. Additionally, it is confirmed that VC portfolio firms exhibit a positive relationship between risk and return measured by total risk. Finally, we find that stock price returns at firm level are lower than that implied by the associated levels of risk. Consequently, this may make individual investors hesitate to directly buy unlisted startups' stocks even when investment in individual startup companies guarantees high risk-high returns relationship.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.3
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• pp.263-267
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• 2010

Although electricity market structures may be different from each country, they have a long-term forward market and a short-term spot market in general. Particularly, a bilateral contract transacted at a long-term forward market fixes the electricity price between a genco and a customer so that the customer can avoid risk due to price-spike in the spot market. The genco also can make an efficient risk-hedging strategy through the bilateral contract. In this paper, we propose a new mechanism for deriving the optimal bilateral contract price using game theory. This mechanism can make the customer reveal his true willingness to purchase so that an adequate bilateral contract price is derived.

• Journal of East Asia Management
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• v.3 no.1
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• pp.41-55
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• 2022

This study investigates whether foreign investors' behavior is involved in firm-specific investor sentiment. Because the mixed role of foreign investors on investor sentiment formation seems to exist in the Korean stock market, it needs to examine the moderate or incremental effect of foreign investors on the stock price crash risk which is due to investor sentiment. The analysis results using Korea Stock Exchanges - listed firms for the period of 2011-2019 show the increased future stock price crash risk which is attributable to high investor sentiment is mitigated for firms with the high foreign ownership, indicating the moderate effect. This study expands the literature on the foreign investors' behavior in the Korean stock market, by showing foreign investors are not involved in firm-specific investor sentiment, which improves market's efficiency in the Korean stock market. Also, the paper is valuable to the academic and practice field in that the findings shed light on the foreign investors' mitigating role in stock price crashes in the behavioral finance perspective.

• The Journal of Asian Finance, Economics and Business
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• v.6 no.3
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• pp.19-26
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• 2019

The paper aims to measure stock price volatility on Ho Chi Minh stock exchange (HSX). We apply symmetric models (GARCH, GARCH-M) and asymmetry (EGARCH and TGARCH) to measure stock price volatility on HSX. We used time series data including the daily closed price of VN-Index during 1/03/2001-1/03/2019 with 4375 observations. The results show that GARCH (1,1) and EGARCH (1,1) models are the most suitable models to measure both symmetry and asymmetry volatility level of VN-Index. The study also provides evidence for the existence of asymmetric effects (leverage) through the parameters of TGARCH model (1,1), showing that positive shocks have a significant effect on the conditional variance (volatility). This result implies that the volatility of stock returns has a big impact on future market movements under the impact of shocks, while asymmetric volatility increase market risk, thus increase the attractiveness of the stock market. The research results are useful reference information to help investors in forecasting the expected profit rate of the HSX, and also the risks along with market fluctuations in order to take appropriate adjust to the portfolios. From this study's results, we can see risk prediction models such as GARCH can be better used in risk forecasting especially.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.140-141
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• 2015

Although the depression of oversea construction market becomes more serious recent years, asian construction market is relatively dynamic, particularly in china. However, few research has been conducted about how to manage construction projects in china as foreign developers. Four important risks are identified from series of surveys using the WBS-RBS method, the result shows that the main risk of tender stage is 'Tender max price error', ' Bill of quantities error', 'Unusual low price' and 'Moral risk' respectively.