A comparative assessment of mortality among the widowers and widows in Taiwan

This paper explores the impact of spousal death on estimated mortality between the widowers and widows among the middle aged and elderly in Taiwan. Subject data is obtained from the Survey of Health and Living Status of the Middle Aged and Elderly in Taiwan, a study conducted in 1996 that encompassed observations 50 years of age and older. Survey data was linked to 1996-2003 national death registry data. Cox proportional hazard model is used to determine the survival rates between the widowers and widows. Main empirical results confirm that the relatively higher mortality hazard associated with being widowhood groups regardless of widowers and widows. Nevertheless, widows face a higher mortality risk than widowers for who compared to their counterparts. In addition, the influences of family and social networks on mortality risk tend to be more important than health status.

Estimating fixed-effect panel stochastic frontier models by model transformation

Traditional panel stochastic frontier models do not distinguish between unobserved individual heterogeneity and inefficiency. They thus force all time-invariant individual heterogeneity into the estimated inefficiency. Greene (2005) proposes a true fixed-effect stochastic frontier model which, in theory, may be biased by the incidental parameters problem. The problem usually cannot be dealt with by model transformations owing to the nonlinearity of the stochastic frontier model. In this paper, we propose a class of panel stochastic frontier models which create an exception. We show that first-difference and within-transformation can be analytically performed on this model to remove the fixed individual effects, and thus the estimator is immune to the incidental parameters problem. Consistency of the estimator is obtained by either N→∞ or T→∞, which is an attractive property for empirical researchersStochastic frontier models; Fixed effects; Panel data

Demarcating stable and turbulent regimes in Taiwan's stock market

Various trading rules involving derivatives have been widely applied by practitioners under a wide range of market conditions to date, however, few econometric models can provide a way to accurately decide when to apply those strategies. In this paper, we employ the Innovation Regime-Switching (IRS) model (Kuan, et al, 2005, JBES) to separate stock price sample periods into stable and turbulent regimes on the basis of their dynamic behaviors. Our results show that, based on regime identification, we can obtain satisfactory profits by implementing appropriate and timely derivative strategies.Bear market

Survival Analysis for Unobserved Heterogeneity on Estimated Mortality in Taiwan

The purpose of this study provides evidences on the effects of unobserved heterogeneity on estimated mortality among the middle aged and elderly in Taiwan. The data used is from the Survey of Health and Living Status of the Middle Aged and Elderly in Taiwan (aged 50 to 66), and the mortality information was linked to 1996-2003 national death registry data. The Weibull models are used to estimate the effects of unobserved heterogeneity on mortality. Main empirical results confirm that, after considering unobserved heterogeneity, most estimated coefficients on the mortality regressors are larger in magnitude that the corresponding coefficients in the reference model. Especially, the terms of health care utilization have larger unobserved heterogenity on estimated mortality. Therefore, if the government policies can concern more unobserved heterogenity of health care utilization that might useful to decrease the mortality for the elderly.

Similarity Solutions of a Class of Perturbative Fokker-Planck Equation

In a previous work, a perturbative approach to a class of Fokker-Planck equations, which have constant diffusion coefficients and small time-dependent drift coefficients, was developed by exploiting the close connection between the Fokker-Planck equations and the Schrodinger equations. In this work, we further explore the possibility of similarity solutions of such a class of Fokker-Planck equations. These solutions possess definite scaling behaviors, and are obtained by means of the so-called similarity method

Spontaneous spin ordering of Dirac spin liquid in a magnetic field

The Dirac spin liquid was proposed to be the ground state of the spin-1/2 Kagome antiferromagnets. In a magnetic field $B$, we show that the state with Fermi pocket is unstable to the Landau level (LL) state. The LL state breaks the spin rotation around the axis of the magnetic field. We find that the LL state has an in-plane 120$^{\circ}$ $q=0$ magnetization $M$ which scales with the external field $M\sim B^{\alpha}$, where $\alpha$ is an intrinsic calculable universal number of the Dirac spin liquid. We discuss the related experimental implications which can be used to detect the possible Dirac spin liquid phase in Herbertsmithite ZnCu$_3$(OH)$_6$Cl$_2$.Comment: rewritten for clarit

Local Cyber-physical Attack with Leveraging Detection in Smart Grid

A well-designed attack in the power system can cause an initial failure and then results in large-scale cascade failure. Several works have discussed power system attack through false data injection, line-maintaining attack, and line-removing attack. However, the existing methods need to continuously attack the system for a long time, and, unfortunately, the performance cannot be guaranteed if the system states vary. To overcome this issue, we consider a new type of attack strategy called combinational attack which masks a line-outage at one position but misleads the control center on line outage at another position. Therefore, the topology information in the control center is interfered by our attack. We also offer a procedure of selecting the vulnerable lines of its kind. The proposed method can effectively and continuously deceive the control center in identifying the actual position of line-outage. The system under attack will be exposed to increasing risks as the attack continuously. Simulation results validate the efficiency of the proposed attack strategy.Comment: Accepted by IEEE SmartGridComm 201