The Causal Relationship between Economic Policy Uncertainty and Stock Market: A Panel Data Analysis

Tsung-Pao Wu,Shu-Bing Liu,Shun-Jen Hsueh 한국국제경제학회 2016 International Economic Journal Vol.30 No.1

This study applies recently developed bootstrap panel Granger causality, proposed by Kónya, to investigate a causal link between economic policy uncertainty and stock markets in nine countries over monthly periods from 2003M01 to 2014M12 (Kónya (2006 Kónya, L. (2006). Exports and growth: Granger causality analysis on OECD countries with a panel data approach. Economic Modelling, 23, 978–992. doi: 10.1016/j.econmod.2006.04.008 [CrossRef], [Web of Science ®] ) Exports and growth: Granger causality analysis on OECD countries with a panel data approach. Economic Modelling, 23, 978–992). The modeling allows us to examine both the cross-sectional dependency and the country-specific heterogeneity. The empirical results indicate that not all countries are alike, and that the theoretical prediction that stock markets fall at the announcement of a policy change is not always supported. Specifically, this work finds evidence of the stock market leading hypothesis for India, Italy, and Spain, while the economic policy uncertainty leading hypothesis cannot be rejected for the United Kingdom. In addition, the neutrality hypothesis was supported in the remaining countries (Canada, China, France, Germany and the United States), while the feedback hypothesis, however, is not found. The findings of this study could provide important policy implications for these nine countries.

Electrical Measurements of an AlGaN/GaN High-electron-mobility Transistor Structure Grown on Si

Zhi-Yao Zhang,Shun-Tsung Lo,Li-Hung Lin,Kuang Yao Chen,J. Z. Huang,Zhi-Hao Sun,C.-T. Liang,N. C. Chen,Chin-An Chang,P. H. Chang 한국물리학회 2012 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.61 No.9

We report on magnetotransport results for an Al_0.15Ga_0.85N/GaN high-electron-mobility-transistor structure grown on a p-type Si (111) substrate. Our results show that there exists an approximately temperature (<i>T</i>)-independent point, which could be ascribed to a direct transition from a weak insulator to a high Landau level filling factor quantum Hall state, exists in the longitudinal resistivity ρ_xx. The Hall resistivity decreases with increasing <i>T</i>, compelling experimental evidence for electron-electron interaction effects in a weakly-disordered two-dimensional (2D) system. We find that electron-electron interaction effects can be estimated and eliminated, giving rise to a corrected nominally temperature-independent Hall slope. By fitting the low-field magnetotransport data to conventional 2D weak localization theory, we find that the dephasing rate 1/τ_φ is proportional to <i>T</i>. Moreover, 1/τ_φ is finite as <i>T</i> → 0, evidence for zero-temperature dephasing in our system.

Thermometry for Dirac Fermions in Graphene

Fan-Hung Liu,Chang-Shun Hsu,Shun-Tsung Lo,Chiashain Chuang,Lung-I Huang,Tak-Pong Woo,Chi-Te Liang,Y. Fukuyama,Y. Yang,R. E. Elmquist,Pengjie Wang,Xi Lin 한국물리학회 2015 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.66 No.1

We use both the zero-magnetic-field resistivity and the phase coherence time determined by weaklocalization as independent thermometers for Dirac fermions (DF) in multilayer graphene. In thehigh current (I) region, there exists a simple power law TDF / I0.5, where TDF is the effective Diracfermion temperature for epitaxial graphene on SiC. In contrast, TDF / I1 in exfoliated multilayergraphene. We discuss possible reasons for the different power laws observed in these multilayergraphene systems. Our experimental results on DF-phonon scattering may find applications ingraphene-based nanoelectronics.

Shareholdings of Board Members and Corporate Performance: A Panel Quantile Regression Analysis

Shu-Bing Liu,Shun-Jen Hsueh,Tsung-Pao Wu 연세대학교 동서문제연구원 2017 Global economic review Vol.46 No.3

This paper investigates the impact of board member shareholdings on corporate performance in China and Taiwan, and employs unbalanced panel data over the period 2005– 2009. In view of the inconsistent empirical findings in the literature and the limitations of least squares regressions, this study adopts a quantile regression method including fixed effects (FE) models. An important finding is that a significant, positive relationship exists between the shareholdings of board members and accounting measures of performance, and this relationship only exists for the more profitable firms in China, while a uniformly significant and positive relationship exists across all quantiles between the shareholdings of board members and accounting measures of performance in Taiwan. These findings, which cannot be obtained using a FE model, suggest that board members can influence firm performance through holding shares in most Taiwan firms and profitable Chinese firms.

Non-monotonic Magnetoresistivity in Two-dimensional Electron Systems

Yi-Ting Wang,Tak-Pong Woo,Shun-Tsung Lo,김길호,Chi-Te Liang 한국물리학회 2014 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.65 No.10

The connection being studied is the one between the non-monotonic magnetoresistivity (MR) andthe electron-electron interaction (EEI) correction in weakly-disordered two-dimensional electronsystems (2DESs) in the ballistic region kBT/~ > 1, where kB, T, , and ~ are the Boltzmannconstant, the temperature, the scattering time, and the reduced Planck constant, respectively. Atzero magnetic field, a transition of the resistivity (T) from the insulating region d/dT < 0 tothe metallic region d/dT > 0 is observed. The MR shows a maximum, and with increasing T,the position of the MR maximum in B increases for both GaAs-based (sample A) and GaN-based(sample B) 2DESs. Our data suggest that the EEI plays an important role in such a non-monotonicMR effect and in the temperature dependence of the resistivity.

Telbivudine-Induced Myopathy: Clinical Features, Histopathological Characteristics, and Risk Factors

Min-Yu Lan,Hui-Chen Lin,Tsung-Hui Hu,Shu-Fang Chen,Chien-Hung Chen,Yung-Yee Chang,King-Wah Chiu,Tsu-Kung Lin,Shun-Sheng Chen 대한신경과학회 2023 Journal of Clinical Neurology Vol.19 No.1

Background and Purpose Oral nucleos(t)ide analogs (NAs) are the mainstay treatment for chronic hepatitis B (CHB). Myotoxicity is an important extrahepatic effect related to NA treatment. Telbivudine is the NA for CHB that is frequently associated with muscle-related side effects. The risk factors for telbivudine-induced myopathy (TIM) are not yet clear. Methods This study characterized the clinical, magnetic resonance images (MRI), and pathological features of 12 TIM cases. A group of telbivudine-tolerant (TT) patients with CHB who received regular telbivudine treatment during the same period without the occurrence of myopathy was collected. Demographic and clinical factors were compared between the patients with TIM and the TT controls. Factors independently associated with TIM were identified using logistic regression analysis. Results The patients with TIM (males/females: 7/5, mean age: 57 years) developed myopathy after using telbivudine for a median period of 19.5 months. Muscle histopathology revealed abnormal proliferation, subsarcolemmal or sarcoplasmic accumulations, and ultrastructural defects of mitochondria. When compared with TT cases, patients with TIM had a lower estimated glomerular filtration rate and were more frequently positive for hepatitis B e antigen (HBeAg). Conclusions Mitochondrial abnormalities are characteristic histopathological features, and impaired renal function and HBeAg positivity are risk factors for TIM. Telbivudine-induced mitochondrial dysfunction and immune activation related to mitochondrial damage and HBeAg serostatus changes may underlie TIM. Constant clinical surveillance of myopathy during telbivudine treatment is needed due to the significant latency of its development. Dose adjustment for impaired renal function does not eliminate the risk of TIM occurrence.

On the direct insulator-quantum Hall transition in two-dimensional electron systems in the vicinity of nanoscaled scatterers

Liang, Chi-Te,Lin, Li-Hung,Kuang Yoa, Chen,Lo, Shun-Tsung,Wang, Yi-Ting,Lou, Dong-Sheng,Kim, Gil-Ho,Yuan-Huei, Chang,Ochiai, Yuichi,Aoki, Nobuyuki,Chen, Jeng-Chung,Lin, Yiping,Chun-Feng, Huang,Lin, Sh Springer 2011 Nanoscale research letters Vol.6 No.1

<P>A direct insulator-quantum Hall (I-QH) transition corresponds to a crossover/transition from the insulating regime to a high Landau level filling factor ν > 2 QH state. Such a transition has been attracting a great deal of both experimental and theoretical interests. In this study, we present three different two-dimensional electron systems (2DESs) which are in the vicinity of nanoscaled scatterers. All these three devices exhibit a direct I-QH transition, and the transport properties under different nanaoscaled scatterers are discussed.</P>