이상원 교수

This paper investigates the sampling behavior of the quasi-maximum likelihood estimator of the Gaussian GARCH(1,1) model. The rescaled variable (the ratio of the disturbance to the conditional standard deviation) is not required to be Gaussian nor independent over time, in contrast to the current literature. The GARCH process may be integrated (α + β = 1), or even mildly explosive (α + β > 1). A bounded conditional fourth moment of the rescaled variable is sufficient for the results. Consiste

This study analyzed the coverage by two partisan South Korean newspapers of the Middle East respiratory syndrome (MERS) pandemic, examining differences in their use of news frames and cited sources. A content analysis revealed that Hankyoreh, the left-wing newspaper, placed more emphasis on attributing responsibility to the government and society. In contrast, Chosun Ilbo, the right-wing newspaper, placed more emphasis on attributing responsibility to the individual. Severity/uncertainty, econom

In understanding user experience issues, it is necessary to consider contextual features in user interaction with an application. The present study aims to examine the differences among applications with difference contexts of use (perceived type: interaction styles based on use purposes) in terms of the relationships between user perception (perceived usability and perceived aesthetics) and emotion (valence and arousal). A study was performed using 15 existing websites from various domains. Fro

Since the introduction of smartphones in South Korea, users have shown quick and positive responses to them. This study explores issues in user satisfaction and develops strategies for user retention of a specific mobile telecommunications service provider in Korea. We presented a face-to-face questionnaire to 4398 participants representing nationwide characteristics of Korean users. Mobile telecommunications services and features were divided into two factors based on benefit segmentation and w

Employing panel data from 36 countries, this study examines whether diverse factors such as existing knowledge stock, research and development (R&D) financed by government, R&D performed by government, education and economic freedom have influenced biotechnology innovation. The results indicate that existing knowledge stock is a driver of biotechnology innovation, reflecting potential positive path dependencies. This study also suggests the possibility that as the share of government R&D finance

This study proposes a new approach to developing a user behavior model to explain how a user finds the optimal use. This is achieved by considering user concerns, task significances, affordances, and emotional responses as the interaction components and by exploring behavior sequences for a goal in using a product the first time. The tasks in the same group at each level in the user concern structure are therefore in a competing relationship in going up to a higher task. The task tree with the s

In general, during decision making or negotiations, the investor and the investee may often have different opinions which result in conflicts. So, an objective standard to mitigate potential conflicts between investors and investees should be provided since it is highly important that rational decisions must be made when choosing investments from various options. However, the models currently used come with some problems for several reasons, for instance, the arbitrariness of the evaluator, the