Social policy for users of information technology : young people and internet addiction in Korea

The Internet has conferred many benefits, but it also has negative effects including addiction patterns termed “Internet addiction”. Many studies have been inclined to focus on discovering psychological symptoms. However, they have not usually considered young people’s relationships, which can themselves lead to Internet addiction. This study gathers the life experiences of young people with an ‘Internet addiction pattern’ in order to understand better their relationships and circumstances. South Korea was chosen as the main focus of this study. From the Foucauldian perspective, the relationships produce power in new ways, wherever they meet and whenever they talk, with knowledge through their abilities, topics or information. This knowledge may categorise peers according to status and ability to use the Internet. These factors activate a ‘power network’ in ‘their own world’. As a result, Internet addiction situation is interpreted as a loss of balance in using the Internet and the research findings demonstrate how this process is influenced by the development of a set of power relations between young people within ‘their own world’. The recommendations are included, mainly ways to participate in the young people’s concerns and to relate to their lives so as to understand the real situation and reduce the problems

Quantum Goos-H\"{a}nchen shift and tunneling transmission at a curved step potential

We study the quantum Goos-H\"{a}nchen (GH) shift and the tunneling transmission at a curved step potential by investigating the time evolution of a wave packet. An initial wave packet is expanded in terms of the eigenmodes of a circular step potential. Its time evolution is then given by the interference of their simple eigenmode oscillations. We show that the GH shift along the step boundary can be explained by the energy-dependent phase loss upon reflection, which is defined by modifying the one-dimensional (1D) effective potential derived from the 2D circular system. We also demonstrate that the tunneling transmission of the wave packet is characterized by a free-space image distant from the boundary. The tunneling transmission exhibits a rather wide angle divergence and the direction of maximum tunneling is slightly rotated from the tangent at the incident point, which is consistent with the time delay of the tunneling wave packet computed in the 1D modified effective potential

The Reliability and the Applicability of the Residual Income-based Valuation Model : Theoretical Augmentation of the Linear Information Dynamics Model and Its Validity Compared with Ohlson (1995) and Edwards-Bell-Ohlson Approaches.

Following the seminal theoretical works of Ohlson (1995) and Feltham and Ohlson (1995, 1996), many researchers have tried to investigate the linear information dynamics (LID) model's validity empirically. However, empirical applications of the LID approach to residual income-based equity valuation, such as Dechow, Hutton and Sloan (1999) (DHS) and Myers (1999b), have produced estimates of firm value that are substantially lower on average than corresponding observed market values. DHS's results that show the quite large downward bias of the value estimates based on Ohlson (1995), together with the work of Myers (1999b) that includes the RI intercept term in the pricing model, motivate me to augment the Ohlson model in order to capture the impact of the intercept terms on the residual income forecasts and firm values. I argue that the large negative bias in LID-based value estimates might be attributable to failure to deal fully with the effects of conservative accounting in projecting residual income. I term the augmented model, which incorporates residual income (RI) and 'other information' (OI) intercepts into the linear information dynamics, as the 'intercept-inclusive' LID model. I also show that the Feltham and Ohlson (1995) LID model as well as the Ohlson (1995) LID model are special cases of the 'intercept-inclusive' LID model. The main objective of the thesis is thus to examine whether the 'intercept-inclusive' LID model produces more reliable value estimates than the extant Rl-based valuation models: the Ohlson (1995) LID-type and the EBO-type valuation models. Using U. S. (Chapter 4) and U. K. (Chapter 6) data, I show that use of a LID that impounds the effects of conservative accounting, as reflected in analyst forecast-based residual income projections, produces value estimates that are substantially less biased than those extant Rl-based models. The thesis also addresses a potentially important issue of the different applicability under different conditions of different Rl-based valuation models in Chapter 7. This is based on the idea that the models' relative applicability can differ across various firm-specific characteristics and properties, because the implementation procedures and underlying assumptions of competing models are apparently different. Among some firm-specific ex-ante variables, eamings-to-price ratio, market-to-book ratio and analyst-based one-year ahead RI forecast-to-book ratio seem to be influential with regard to the applicability of models. Despite some contributions of this study, there are also several limitations that need to be explored in further research. In particular, value estimates based on the 'intercept-inclusive' LID approach are very sensitive to the assumed discount rate and growth rate. Moreover, the 'intercept-inclusive' LID model does not appear to improve the overall accuracy of value estimates. Together with the evidence of different applicability across firm-specific characteristics, how some firm-specific ex-ante variables can be used to modify the models and how to estimate firm-specific discount rates and growth rates could be important issues in further research

Revisiting The Certifying Role Of Financial Intermediaries On IPOs

This paper re-examines the role of commercial banks, investment banks, and venture capitalists in monitoring and certifying the value of the firms that went public in the 2000s. We find that investment banks that have better reputations are associated with larger underpricing for venture-capital-backed IPOs, but not for non-venture-capital-backed IPOs. The partial adjustment phenomenon observed in Carter et al. (2001) exists only for venture-capital-backed IPOs. The presence of venture capital is inversely related to IPO underpricing only when venture capitalists certify small firms. We do not find that the presence of bank debt reduces IPO underpricing. In addition, we do not find any substitutive or complementary role between commercial banks and venture capitalists in certifying IPOs