• 한국농공학회논문집
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• 제49권3호
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• pp.11-20
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• 2007

Estimation of crop consumptive use is a key term of agricultural water resource systems design and operation. The 10-year return period drought has special aspects as a reference period in design process of irrigation systems in terms of agricultural water demand analysis so that crop evapotranspiration (ETc) about the return period also has to be analyzed to assist understanding of crop water requirement of paddy rice. In this study, The ETc of 10-year return period drought was computed using frequency analysis by 54 meteorological stations. To find an optimal probability distribution, 8 types of probability distribution function were tested by three the goodness of fit tests including ${\chi}^2$(Chi-Square), K-S (Kolmogorov-Smirnov) and PPCC (Probability Plot Correlation Coefficient). Optimal probability distribution function was selected the 2-parameter Log-Normal (LN2) distribution function among 8 distribution functions. Using the two selected distribution functions, the ETc of 10-year return period drought was estimated for 54 meteorological stations and compared with prior study results suggested by other researchers.

• Communications for Statistical Applications and Methods
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• 제21권6호
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• pp.501-512
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• 2014

Stylized facts on asset return are fat-tail, asymmetry, volatility clustering and structure changes. This paper simultaneously captures these characteristics by introducing a multi-regime models: Finite mixture distribution and regime switching GARCH model. Analyzing the daily KOSPI return from $4^{th}$ January 2000 to $30^{th}$ June 2014, we find that a two-component mixture of t distribution is a good candidate to describe the shape of the KOSPI return from unconditional and conditional perspectives. Empirical results suggest that the equality assumption on the shape parameter of t distribution yields better discrimination of heterogeneity component in return data. We report the strong regime-dependent characteristics in volatility dynamics with high persistence and asymmetry by employing a regime switching GJR-GARCH model with t innovation model. Compared to two sub-samples, Pre-Crisis (January 2003 ~ December 2007) and Post-Crisis (January 2010 ~ June 2014), we find that the degree of persistence in the Pre-Crisis is higher than in the Post-Crisis along with a strong asymmetry in the low-volatility (high-volatility) regime during the Pre-Crisis (Post-Crisis).

• 아태비즈니스연구
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• 제11권4호
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• pp.37-48
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• 2020

Purpose - This study empirically investigates whether the risk property included in fat-tails of return distributions is systematic or unsystematic based on the devised statistical methods. Design/methodology/approach - This study devised empirical designs based on two traditional methods: principal component analysis (PCA) and the testing method of portfolio diversification effect. The fatness of the tails in return distributions is quantitatively measured by statistical probability. Findings - According to the results, the risk property in the fat-tails of return distributions has the economic meanings of eigenvalues having a value greater than 1 through PCA, and also systematic risk that cannot be removed through portfolio diversification. In other words, the fat-tails of return distributions have the properties of the common factors, which may explain the changes of stock returns. Meanwhile, the fatness of the tails in the portfolio return distributions shows the asymmetric relationship of common factors on the tails of return distributions. The negative tail in the portfolio return distribution has a much closer relation with the property of common factors, compared to the positive tail. Research implications or Originality - This empirical evidence may complement the existing studies related to tail risk which is utilized in pricing models as a common factor.

• 한국조리학회지
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• 제22권6호
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• pp.52-60
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• 2016

This study attempts to measure the financial performance of the food distribution company. In order to achieve the goal, this study have measured the ratios of ROE, ROA applying the DuPont analysis, which have been demonstrated with tables to show the change periodically. DuPont analysis is based on analysis of Return on Equity (ROE) & Return on Investment (ROI). The return on equity disaggregate performance into three components: Net Profit Margin, Total Asset Turnover, and the Equity Multiplier. The return on investment consists of Assets Turnover (Operating Income${\times}$Total Assets) and Profit Margin (EBIT${\times}$Operating Income). From the study it if found that Hyundae Green Food's Financial performance is high followed by Foodmerce and then Dongwon home food and Lotte Food. The four companies are significant at their level. In conclusion, ROE & ROI is the most comprehensive measure of profitability of a firm. It considers the operating and investing decisions can be made as well as the financing and their leverage-related decisions.

• Journal of the Korean Data and Information Science Society
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• 제18권2호
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• pp.289-300
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• 2007

The stock return is changed by factors of inside and outside or is changed by factor of market system. But most studies have not considered the changes of stock return distribution when estimate the VaR. Such study may lead us to wrong conclusion. In this paper we calculate the VaR of price-to-earnings ratios by the distribution that have considered the change point and used transformation to satisfy normal distribution.

• 상하수도학회지
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• 제30권1호
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• pp.41-49
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• 2016

In this study, rainfall characteristics with stationary and non-stationary perspectives were analyzed using generalized extreme value (GEV) distribution and Gumbel distribution models with rainfall data collected in major cities of Korea to reevaluate the return period of sewer flooding in those cities. As a result, the probable rainfall for GEV and Gumbel distribution in non-stationary state both increased with time(t), compared to the stationary probable rainfall. Considering the reliability of ${\xi}_1$, a variable reflecting the increase of storm events due to climate change, the reliability of the rainfall duration for Seoul, Daegu, and Gwangju in the GEV distribution was over 90%, indicating that the probability of rainfall increase was high. As for the Gumbel distribution, Wonju, Daegu, and Gwangju showed the higher reliability while Daejeon showed the lower reliability than the other cities. In addition, application of the maximum annual rainfall change rate (${\xi}_1{\cdot}t$) to the location parameter made possible the prediction of return period by time, therefore leading to the evaluation of design recurrence interval.

• 유통과학연구
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• 제21권10호
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• pp.77-84
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• 2023

Purpose: This study aims to determine the impact of green accounting on the distribution of company financial performance. Green Accounting is seen as an accounting approach that considers the environmental impact of business activities and the distribution of financial performance which is expected to provide great benefits to the company. Research Design Data and Methodology: The population of this study is 168 manufacturing companies listed on the Indonesia Stock Exchange from 2018 to 2020. The research theory uses the Legitimacy Theory and the Shareholder Theory. Research data were analyzed using multiple regression models with purposive sampling. Green Accounting in this study uses environmental cost proxies using Return on Capital Employed (ROCE). Financial performance uses the Return on Equity (ROE) proxy. Results: research shows that the influence of green accounting can provide important input to operational managers in manufacturing companies in making decisions regarding environmental costs and environmental protection that will provide economic benefits for the company. In addition, these findings also clarify the great benefits of green accounting policies for a company's production process. Conclusion: Green Accounting has a long-term impact through the company's financial performance. Green Accounting can be the basis for companies in deciding whether to invest or not.

• 유통과학연구
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• 제21권5호
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• pp.101-111
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• 2023

Purpose: The purpose of this paper is to examine the effect of the VKOSPI index on short-term stock returns after a large-scale stock price shock of individual stocks of firms in the distribution industry in Korea. Research design, data, and methodology: This study investigates the effect of the change of the VKOSPI index or investor mood on abnormal returns after the event date from January 2004 to July 2022. The significance of the abnormal return, which is obtained by subtracting the rate of return estimated by the market model from the rate of actual return on each trading day after the event date, is determined based on T-test and multifactor regression analysis. Results: In Korea's distribution industry, the simultaneous occurrence of a bad investor mood and a large stock price decline, leads to stock price reversals. Conversely, the simultaneous occurrence of a good investor mood and a large-scale stock price rise leads to stock price drifts. We found that the VKOSPI index has strong explanatory power for these reversals and drifts even after considering both company-specific and event-specific factors. Conclusions: In Korea's distribution industry-related stock market, investors show an asymmetrical behavioral characteristic of overreacting to negative moods and underreacting to positive moods.

• 응용통계연구
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• 제25권1호
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• pp.29-43
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• 2012

주식, 환율 등과 같은 금융자료의 수익률의 분포는 정규분포에 비해 꼬리가 두껍고, 좌우 비대칭성을 보인다. 조건부수익률이 정규분포를 따른다고 가정한 GARCH 모형을 이용하여 VaR을 추정하였을 때, 이러한 비정규성 때문에 적절한 추정이 이루어지지 않고, VaR을 초과하는 손실의 발생과정에 군집(clustering)현상이 발생하는 문제점이 있다. 이러한 문제를 해결하기 위해, 본 논문에서는 조건부수익률의 분포로 unbounded Johnson 분포를 이용한 GARCH 모형을 이용하여 VaR을 추정한다. 또한, 조건부수익률이 각각 정규분포, Student-t 분포를 따르는 GARCH 모형의 경우와 비교하였다. 초과손실 발생과정 자료를 이용하여 실패율검정과 군집성검정을 통해 조건부수익률 분포로 unbounded-Johnson 분포를 사용하는 방법의 타당성을 살펴보았다. Unbounded Johnson 분포가 조건부수익률 분포로 주어지는 GARCH 모형의 경우는 과소, 과대추정을 하지 않고, 군집현상 또한 발생하지 않아 적절한 추정을 하고 있음을 확인하였다.

• Journal of the Korean Data and Information Science Society
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• 제21권2호
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• pp.219-229
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• 2010

자산을 운용할 때 다양한 위험요인의 증가로 인해 위험관리에 대한 많은 연구가 진행되어왔으며, 통합적인 위험관리기법의 필요성이 대두됨에 따라 개발된 많은 방법 중의 하나가 리스크값이다. 현재까지 연구된 많은 리스크값의 추정과정에서 중요한 과제는 수익률분포의 비대칭성 및 두꺼운 꼬리와 같은 비정규성과 관련된 문제들을 해결하는 것이다. 대부분의 수익률 분포는 첨도가 매우 큰 양수값을 가지며 약한 음수값의 왜도를 갖는다. 본 연구에서는 실제 금융자산 수익률분포에 여러 종류의 대체분포들을 이용하여 실제의 수익률 분포에 적합한 분포를 선정하여 리스크값를 추정한다. 정규분포를 포함한 대체분포들을 이용하여 추정한 리스크값들이 실제 분포로부터 추정한 리스크값에 얼마나 일치하는지를 비교 연구한다. 다양한 대체분포 중에서 실제 분포에 정규혼합분포가 가장 적합하였으며, 이 정규혼합분포를 이용하여 추정한 리스크값과 다른 대체분포를 이용하여 구한 리스크값보다 정확함을 실증 자료를 통해 보였다.