• Journal of Korea Port Economic Association
• /
• v.30 no.3
• /
• pp.1-14
• /
• 2014

This paper aims at measuring how new information is incorporated into volatility estimates. Various GARCH models are compared and estimated with daily BDI(Baltic Dry Index) data. While most researchers agree that volatility is predictable, they differ on how this volatility predictability should be modelled. This study, hence, introduces the asymmetric or leverage volatility models, in which good news and bad news have different predictability for future. We provide the systematic comparison of volatility models focusing on the asymmetric effect of news on volatility. Specifically, three diagnostic tests are provided: the sign bias test, the negative size bias test, and the positive size bias test. From the Ljung-Box test statistic for twelfth-order serial correlation for the level we do not find any significant serial correlation in the unpredictable BDI. The coefficients of skewness and kurtosis both indicate that the unpredictable BDI has a distribution which is skewed to the left and significantly flat tailed. Furthermore, the Ljung-Box test statistic for twelfth-order serial correlations in the squares strongly suggests the presence of time-varying volatility. The sign bias test, the negative size bias test, and the positive size bias test strongly indicate that large positive(negative) BDI shocks cause more volatility than small ones. This paper, also, shows that three leverage models have problems in capturing the correct impact of news on volatility and that negative shocks do not cause higher volatility than positive shocks. Specifically, the GARCH model successfully reveals the shape of the news impact curve and is a useful approach to modeling conditional heteroscedasticity of daily BDI.

• The Journal of the Korea Contents Association
• /
• v.21 no.12
• /
• pp.436-447
• /
• 2021

The boycott of Japanese products triggered by Japan's economic retaliation has heated up the Republic of Korea. This study examined the factors affecting the boycott participation intention in 217 college students and ordinary people in their 20s and 30s. The results of the study showed that perceived egregiousness, self-efficacy, and subjective norm had a positive effect on boycott participation intention, and perceived egregiousness had an indirect effect on boycott participation intention through anger. In addition, these overall impacts were moderated by online and SNS news usage. This study is significant in providing academic and practical implications for understanding boycott phenomena by verifying various influencing factors on consumer boycott intentions and comprehensively reviewing the mediating effect of anger and the moderating effect of online and SNS news usage.

• Journal of the Korea Society of Computer and Information
• /
• v.29 no.2
• /
• pp.51-59
• /
• 2024

This study examines the relationship between the release of the news and the individual stock returns. Investors utilize a variety of information sources to maximize stock returns when establishing investment strategies. News companies publish their articles based on stock recommendation reports of analysts, enhancing the reliability of the information. Defining release of a stock-recommendation news article as an event, we examine its economic impacts and propose a binary classification model that predicts the stock return 10 days after the event. XGBoost and LightGBM models are applied for the study with accuracy of 75%, 71% respectively. In addition, after categorizing the recommended stocks based on the listed market(KOSPI/KOSDAQ) and market capitalization(Big/Small), this study verifies difference in the accuracy of models across four sub-datasets. Finally, by conducting SHAP(Shapley Additive exPlanations) analysis, we identify the key variables in each model, reinforcing the interpretability of models.

• The Journal of the Korea Contents Association
• /
• v.6 no.8
• /
• pp.184-191
• /
• 2006

The purpose of this case study is to understand the characteristics and implication of videojournalist's image expression techniques in the television news programs, comparing with television camera reporter's image expression techniques. Texts chosen in this thesis are 120 programs of KBS2TV 'News Time' which had been on air from July to December in 2005. Shot size, camerawork, shot duration and camera angle of the images were analysed, which had been extracted through the processes of thematic classification. The results of the analysis of thematic classification shows us that videojournalist covered mainly social, economic and cultural news items, almost completely alienated in the fields of hard news as political and health-scientific news items which were very sensitive and influential on the life of the entire people of the nation. The results of the analysis on the characteristics of image expression reveals that videojournalist used one-shot more often than the camera reporter, showing us videojournalist's preference of close news gathering, and videojournalist used following and zooming much more often than camera reporter, showing us videojoumalist's preference of mobile and dynamic cameraworks, and videojournalist used low angles more often than camera reporter, also showing us videojoumalist's preference of candid camera style news gathering.

• Journal of Contemporary Eastern Asia
• /
• v.18 no.2
• /
• pp.118-141
• /
• 2019

In South Korea, as awareness of gender equality increased since the 1990s, policies for gender equality and social awareness of equality have been established. Until recently, however, the gap between men and women in social and economic activities has not reached the globally desired level and led to social conflict throughout the country. In this study, we analyze the content of online news comments to understand the public perception of gender equality and the details of gender conflict and to grasp the emergence and diffusion process of emerging issues on gender equality. We collected text data from the online news that included the word 'gender equality' posted from January 2012 to June 2017 and also collected comments on each selected news item. Through text mining and the temporal semantic network analysis, we tracked the changes in discourse on gender equality and conflict. Results revealed that gender conflicts are increasing in the online media, and the focus of conflict is shifting from 'position and role inequality' to 'opportunity inequality'.

• Korean journal of communication and information
• /
• v.50
• /
• pp.164-186
• /
• 2010

Korean society, suffered from a severe currency crisis in 1997, had scarcely missed another market meltdown in 2008. However, neither economic fundamentals nor has political stability little to do with the recent crises. This paper thus projects the possibility of 'self-fulfilling crisis' in which the media took a critical part in amplifying 'crisis discourses.' For the purpose of understanding of media's impact on such a crisis, at first, this paper chose 'September Crisis in 2008' as a case study. While collecting news articles about the crisis, then, total 118 news articles collected from mainstream newspapers such as DongA-ilbo and Money Today have been analyzed in terms of media frame and discourse strategies. Research results showed that not only has the crisis discourse been shifted by economic situations, but the media re-constructed economic realities in way of justifying their political ideology and loyal readership. Taking those findings into consideration, in final, the authors urged the media to improve their performance by embracing more responsible and professional manners.

• The Korean Journal of Applied Statistics
• /
• v.25 no.6
• /
• pp.889-896
• /
• 2012

In this paper, we propose a statistic to measure investor sentiment. It is a usual phenomenon that an asymmetric volatility (referred to as the leverage effect) is observed in financial time series and is more sensitive to bad news rather than good news. In a bubble state, investors tend to continuously speculate on financial instruments because of optimism about the future; subsequently, prices tend to abnormally increase for a long time. Estimators of the transformation parameter and the skewness based on Yeo-Johnson transformed GARCH models are employed to check whether a bubble or abnormality exist. We verify the appropriacy of the proposed interpretation through analyses of KOSPI and NIKKEI.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2021.05a
• /
• pp.277-278
• /
• 2021

Conflict in public construction projects has increased for the last decades. It not only entails enormous social and economic costs but also makes stakeholders suffer from unnecessary expense and time waste. This study defines the the conflict index for public construction projects based on news data, and calculates conflict index for representative past and current public construction projects that has been deepened conflicts at the national level. The result indicates that the major conflict issue of the 2nd Jeju Airport Project are the environment and location whereas that of the Gaduk New Airport Project are the safety, location and necessity. This approach is expected to enable construction project managers to manage conflicts quantitatively based on comparing with past cases.

• Korean journal of communication and information
• /
• v.72
• /
• pp.52-91
• /
• 2015

The purpose of this study is to examine the effects of attribute agenda-setting and priming through content analysis and a survey about Particulate Matter($PM_{10}$ & $PM_{2.5}$) using both promotional news and general news. The study results were as follows. First, promotional news and general news were found to showcase similar cognitive attributes. Second, the results did not show a significant relationship between highlighted attributes in media coverage and the public's salient attributes, but media attributes had been generally reflected in the public's perception because the public was highly aware of the importance of all media attributes. Third, the recognition of the public's attribute importance affected the direction of public opinion, which resulted in the acceptance of priming effects. Meanwhile, the recognition of the public's attribute importance towards economic damage, international cooperation, individual response, and the recognition of promotional news had affected risk perception. Furthermore, the recognition of promotional news and involvement appeared to have an interaction effect on risk perception.

• Journal of Intelligence and Information Systems
• /
• v.24 no.1
• /
• pp.53-74
• /
• 2018

Since South Korea has an economic structure that has a characteristic which market-dependent on overseas, the tourism industry is considered as a very important industry for the national economy, such as improving the country's balance of payments or providing income and employment increases. Accordingly, the necessity of more accurate forecasting on the demand in the tourism industry has been raised to promote its industry. In the related research, economic variables such as exchange rate and income have been used as variables influencing tourism demand. As information technology has been widely used, some researchers have also analyzed the effect of media on tourism demand. It has shown that the media has a considerable influence on traveler's decision making, such as choosing an outbound destination. Furthermore, with the recent availability of online information searches to obtain the latest information and two-way communication in social media, it is possible to obtain up-to-date information on travel more quickly than before. The information in online media such as blogs can naturally create the Word-of-Mouth effect by sharing useful information, which is called eWOM. Like all other service industries, the tourism industry is characterized by difficulty in evaluating its values before it is experienced directly. And furthermore, most of the travelers tend to search for more information in advance from various sources to reduce the perceived risk to the destination, so they can also be influenced by online media such as online news. In this study, we suggested that the number of online media posting, which causes the effects of Word-of-Mouth, may have an effect on the number of outbound travelers. We divided online media into public media and private media according to their characteristics and selected online news as public media and blog as private media, one of the most popular social media in tourist information. Based on the previous studies about the eWOM effects on online news and blog, we analyzed a relationship between the volume of eWOM and the outbound tourism demand through the panel model. To this end, we collected data on the number of national outbound travelers from 2007 to 2015 provided by the Korea Tourism Organization. According to statistics, the highest number of outbound tourism demand in Korea are China, Japan, Thailand, Hong Kong and the Philippines, which are selected as a dependent variable in this study. In order to measure the volume of eWOM, we collected online news and blog postings for the same period as the number of outbound travelers in Naver, which is the largest portal site in South Korea. In this study, a panel model was established to analyze the effect of online media on the demand of Korean outbound travelers and to identify that there was a significant difference in the influence of online media by each time and countries. The results of this study can be summarized as follows. First, the impact of the online news and blog eWOM on the number of outbound travelers was significant. We found that the number of online news and blog posting have an influence on the number of outbound travelers, especially the experimental result suggests that both the month that includes the departure date and the three months before the departure were found to have an effect. It is shown that online news and blog are online media that have a significant influence on outbound tourism demand. Next, we found that the increased volume of eWOM in online news has a negative effect on departure, while the increase in a blog has a positive effect. The result with the country-specific models would be the same. This paper shows that online media can be used as a new variable in tourism demand by examining the influence of the eWOM effect of the online media. Also, we found that both social media and news media have an important role in predicting and managing the Korean tourism demand and that the influence of those two media appears different depending on the country.