• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.91.4-91
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• 2002

Today, Internal offers WWW(World Wide Web), remote control, file transfer and e-mail service. Among the services, WWW takes large portion because of convenient GUI, easy information search and unlimited information registration. WWW service gives the comfort in life such as goods purchase, information search, real-time news, internet TV and medical diagnosis. Remote Monitoring Server(RMS) Ssystem that uses internet and WWW is constructed for chip mounter. Hardware base consists of RMS, chip mounter and C/S(Customer Service) service. Software includes DBMS and various modules in server home page. Web browser provide product num her, bad product number, troubl...

• The Korean Journal of Financial Management
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• v.14 no.1
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• pp.141-169
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• 1997

본 논문은 시장개설 초기 4개월간의 주가지수 선물수익률과 기초자산인 현물(KOSPI 200) 수익률간의 선도-지연효과를 두 개의 모형을 이용하여 실증검증하였다. 첫 번째 모형은 설명 변수로 선물수익률의 시차변수를 사용하고 종속변수로 현물수익률을 사용했다. 두 번째 모형은 설명변수로 선물수익률의 시차변수를 사용하는 것은 첫 번째 모형과 같으나 종속변수로 ARMA모형에서 구한 현물수익률의 오차항(return innovations)을 사용하였다. 또, 여러 시장조건에서 현물수익률과 선물수익률사이의 선도-지연효과가 특정한 양상을 보이는가를 분석하였다. 좋은 정보와 나쁜 정보, 거래량이 많은 경우와 적은 경우, 변동성이 높은 경우와 낮은 경우로 나누어서 선도-지연효과를 살펴보았다. 실증검증의 결과 KOSPI 200 현물수익률은 ARMA(2,3) 모형이 적합하며 선물이 현물을 10분 이내로 선도한다. 하지만 그 관계는 일방적인 것이 아니어서 15분후에는 현물이 선물을 선도하는 피드백(feed-back) 현상이 나타났다. 좋은 정보(good news)에서는 선물이 현물을 5분정도 선도하고 나쁜 정보(bad news)하에서는 선물 선도현상이 약해진다. 보통 정보(morderate news)하에서는 현물이 선물을 10분내로 선도한다. 거래량이 많은 경우와 변동성이 높은 경우에는 선물이 현물을 선도하는 것이 뚜렷하나 거래량이 적은 경우와 변동성이 낮은 경우에는 선물과 현물간에는 특정한 선도-지연현상이 나타나지 않는다.

• The Korean Journal of Financial Studies
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• v.3 no.2
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• pp.157-185
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• 1996

본 연구는 한국증권시장에서 변동성의 정보비대칭효과를 조건부 이분산모형을 이용하여 검증하고자 하였다. 검증방법으로는 Engle과 Ng (1993)의 연구에 기초하여 정보반응곡선(News impact curve)으로 분석하였다. 분석자료로 1980년 부터 1995년 까지의 한국종합주가지수, 일별 초과수익률자료를 사용하였다. 정보반응곡선에 이용한 모형은 GARCH 모형, EGARCH 모형, TGARCH 모형, AGARCH 모형등 4개의 조건부 이분산 모형이다. 무조건 분산을 이용한 정보 반응곡선의 함수형태로 보면, 분산의 정보반응에 있어서 GARCH 모형은 대칭적으로 반응하며 나머지 조건부 이분산 모형인 EGARCH 모형, TGARCH 모형, 그리고 AGARCH 모형은 비대칭적으로 반응하는 모형임을 알 수 있었다. 실증분석결과 정보반응곡선을 통하여 악재(bad news)정보에 따라 예측하지 못한 주식수익률의 하락이 호재(good news)에 따른 예측하지 못한 주식수익률의 상승보다 더 큰 변동성을 발견할 수 있었다. 그러나 비대칭성의 크기는 그다지 큰 것으로 보이지 않았다. 모형적합성 검정에서도 4개의 조건부 이분산 모형은 모두 적합한 것으로 보인다. 그중에서도 EGARCH 모형과 TGARCH 모형이 상대적으로 주가예측력이 뛰어나 보인다. 그러나 변동성의 정보 비대칭반응을 통계적으로 유의적인 것으로 확인한 모형은 TGARCH모형 뿐이었다.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.1779-1784
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• 2016

Background: Western physicians tend to favour complete disclosure of a cancer diagnosis to the patient, while non-Western physicians tend to limit disclosure and include families in the process; the latter approach is prevalent in clinical oncology practice in India. Few studies, however, have examined patient preferences with respect to disclosure or the role of family members in the process. Materials and Methods: Structured interviews were conducted with patients (N=127) in the medical oncology clinic of a tertiary referral hospital in Bangalore, India. Results: Patients ranged in age from 18-88 (M=52) and were mostly male (59%). Most patients (72%) wanted disclosure of the diagnosis cancer, a preference significantly associated with higher education and English proficiency. A majority wanted their families to be involved in the process. Patients who had wanted and not wanted disclosure differed with respect to their preferences regarding the particulars of disclosure (timing, approach, individuals involved, role of family members). Almost all patients wanted more information concerning their condition, about immediate medical issues such as treatments or side effects, rather than long-term or non-medical issues. Conclusions: While most cancer patients wanted disclosure of their disease, a smaller group wished that their cancer diagnosis had not been disclosed to them. Regardless of this difference in desire for disclosure, both groups sought similar specific information regarding their cancer and largely favoured involvement of close family in decision making. Additional studies evaluating the influence of factors such as disease stage or family relationships could help guide physicians when breaking bad news.

• The Journal of Industrial Distribution & Business
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• v.8 no.5
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• pp.87-93
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• 2017

Purpose - This paper investigates whether managerial overconfidence is associated with firm-specific crash risk. Overconfidence leads managers to overestimate the returns of their investment projects, and misperceive negative net present value projects as value creating. They even use voluntary disclosures to convey their optimistic beliefs about the firms' long-term prospects to the stock market. Thus, the overconfidence bias can lead to managerial bad news hoarding behavior. When bad news accumulates and crosses some tipping point, it will come out all at once, resulting in a stock price crash. Research design, data and methodology - 7,385 firm-years used for the main analysis are from the KIS Value database between 2006 and 2013. This database covers KOSPI-listed and KOSDAQ-listed firms in Korea. The proxy for overconfidence is based on excess investment in assets. A residual from the regression of total asset growth on sales growth run by industry-year is used as an independent variable. If a firm has at least one crash week during a year, it is referred to as a high crash risk firm. The dependant variable is a dummy variable that equals 1 if a firm is a high crash risk firm, and zero otherwise. After explaining the relationship between managerial overconfidence and crash risk, the total sample was divided into two sub-samples; chaebol firms and non-chaebol firms. The relation between how I overconfidence and crash risk varies with business group affiliation was investigated. Results - The results showed that managerial overconfidence is positively related to crash risk. Specifically, the coefficient of OVERC is significantly positive, supporting the prediction. The results are strong and robust in non-chaebol firms. Conclusions - The results show that firms with overconfident managers are likely to experience stock price crashes. This study is related to past literature that examines the impact of managerial overconfidence on the stock market. This study contributes to the literature by examining whether overconfidence can explain a firm's future crashes.

• Journal of the Korea Society of Computer and Information
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• v.7 no.2
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• pp.196-204
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• 2002

This paper examines the price discovery role of the KOSPI 200 futures index for its cash index. It was used the intrady data for KOSPI 200 and futures index from July 1998 to June 2001. The existing Preceding study for KOSPI 200 futures index was used the data of early market installation, but this study is distinguished to use a recent data accompanied with the great volume of transaction and various investors. We established three hypothesis to examine whether there is the price discovery role in the KOPSI 200 futures index and the characteristics of that. First, to examine whether the lead-lag relation is induced by the infrequent trading of component stocks, observations are sorted by the size of the trading volume of cash index. In a low trading volume, the long lead time is reported and the short lead time in a high volume. It is explained that the infrequent trading effect have an influence on the price discovery role. Second, to examine whether the lead-lag relation is different under bad news and good news, observations are sorted by the sign and size of cash index returns. In a bad news the long lead time is reported and the short lead time in a good news. This is explained by the restriction of"short selling" of the cash index Third, we compared estimates of the lead and lag relationships on the expiration day with those on days prior to expiration using a minute-to-minute data. The futures-to-spot lead time on the expiration day was at least as long as other days Prior to expiration, suggesting that "expiration day effects" did not demonstrate a temporal character substantially different form earlier days. Thus, while arbitrage activity may be presumed to be the greatest at expiration, such arbitrage transactions were not sufficiently strong or Pervasive to alter the empirical price relationship for the entire day. for the entire day.

• Journal of the Korean Society for information Management
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• v.24 no.2
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• pp.123-141
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• 2007

It has been known that predicting stock price is very difficult due to a large number of known and unknown factors and their interactions, which could influence the stock price. However, we started with a simple assumption that good news about a particular company will likely to influence its stock price to go up and vice versa. This assumption was verified to be correct by manually analyzing how the stock prices change after the relevant news stories were released. This means that we will be able to predict the stock price change to a certain degree if there is a reliable method to classify news stories as either favorable or unfavorable toward the company mentioned in the news. To classify a large number of news stories consistently and rapidly, we developed and evaluated a natural language processing based multi-stage news classification system, which categorizes news stories into either good or bad. The evaluation result was promising as the automatic classification led to better than chance prediction of the stock price change.

• The Journal of Asian Finance, Economics and Business
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• v.6 no.4
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• pp.45-52
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• 2019

The current study aims to investigate the relationship between tax avoidance and firm risk in an emerging market called Iran. The study population consists of 400 observations and 80 companies listed on the Tehran Stock Exchange (TSE) over a five-year period during 2012 and 2016. The statistical model used in this study is a multivariate regression model; besides, the statistical technique used to test the hypotheses proposed in this research is panel data. The results showed that low effective tax rate (tax avoidance) is more consistent than the higher effective tax rate. Moreover, there is no significant relationship between tax avoidance and future tax rate volatility. The findings also proved that lower effective tax rates are positively associated with future stock price volatility. This implies that since Iranian firms have many financial problems because of economic sanctions, they have a tendency to delay the disclosure of bad news about their firms. Needless to say, when a huge number of negative news reaches its peak, they immediately will enter the market and lead to a remarkable fluctuation in stock prices.

• The Korean Journal of Financial Studies
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• v.11 no.1
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• pp.199-216
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• 2005

본 연구에서는 한국을 포함한 4개국의 주식시장을 대상으로 주식시장에 도달하는 정보의 유형 즉, 정보가 나쁜 뉴스(bad news)이냐 또는 좋은 뉴스(good news)이냐에 따라 주가변동성에 미치는 영향을 실증적으로 분석하였다. 주가변동성은 투자위험을 나타내는 것으로 위험프리미엄(risk premium)과 관련이 있으며, 주가변동성이 높을수록 위험프리미엄이 커져서 기대수익률이 높아지게 된다. 따라서 주가변동성에 관한 연구는 자산가격결정 등 투자자산 관리에 있어서 매우 중요한 시사점을 제공할 수 있을 것이다. 실증분석결과에 의하면 전체기간(1991년~2004년)에서 4개국 모두 예상하지 못한 음(-)의 수익률이 예상하지 못한 양(+)의 수익률보다 주가의 변동성을 더욱 증가시킨 것으로 나타났다. 그리고 그 반응 정도의 크기는 한국이 가장 낮게 나타나고 있다. 즉 주식수익률의 정보의 비대칭성은 4개국 모두 볼 수 있으며, 이중 한국에서 정보의 비대칭성이 가장 약하다는 결과로 해석할 수 있다. 본 연구의 이러한 분석결과는 4개국 모두 주식시장에서 정보유형에 따른 주가변동성의 비대칭적 반응이 존재한다는 것을 실증적으로 보여주는 것이다. 또한 두 개의 하위기간(IMF 전후기간)에서도 주가변동성의 비대칭적 반응이 존재하는 것으로 나타났으며, 특이한 점은 주가변동성의 비대칭적 반응을 나타내는 계수값이 한국, 일본, 홍콩 등 아시아 국가들은 IMF 이후기간에서 감소하는(특히 한국의 경우 대폭 감소함) 반면, 미국의 경우에는 대폭 증가하였다. 이는 아시아권의 경우 금융위기를 겪으면서 투자자들이 나쁜 뉴스에 대해 다소 둔감하게 된 결과인 것으로 해석할 수 있다.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.8
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• pp.51-59
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• 2020

The objective of this study is to enrich the literature by investigating the impact of introduction of index future trading on spot market returns and trading volume in Vietnam. Data used in this study mainly consist of daily VN30-Index and market trading volume series during the period from February 6^th, 2012 to December 31^st, 2019. Using OLS, GARCH(1,1) and EGARCH(1,1) models, the empirical findings consistently confirm that the introduction of index future trading has no impact on the spot market returns. In addition, the results of the EGARCH(1,1) model indicate that the leverage effect on the spot market volatility is existence in HOSE. Specifically, bad news has a greater effect on the market volatility than good news of the same size. Moreover, our empirical findings reveal that the introduction of index future contracts has the positive impact on the underlying market trading volume. Specifically, the trading volume of the post-index futures introduction increases by 7.5 percent compared with the pre-index futures introduction. Finally, the results obtained from the Granger causality test for the relationship between the spot market returns and the future trading activity confirm that only uni-directional causality running from the market returns to the future trading activity exists in HOSE.