Labor market competitiveness and the size of the informal sector

This paper formalizes the dynamics of the informal sector with a special emphasis on the levels of labor market competitiveness in the formal and informal sectors. Specifically, it analyzes the effects of improved productivity and higher entry costs into the formal sector on the size of the informal sector for different degrees of competitiveness in the labor markets. We show that when the informal labor market is competitive while the formal labor market is not, lower production technology in the formal sector or a higher entry cost reduces the size of the informal sector in the long run.     

Spectral Estimation of Covolatility from Noisy Observations Using Local Weights

We propose localized spectral estimators for the quadratic covariation and the spot covolatility of diffusion processes, which are observed discretely with additive observation noise. The appropriate estimation for time‐varying volatilities is based on an asymptotic equivalence of the underlying statistical model to a white‐noise model with correlation and volatility processes being constant over small time intervals. The asymptotic equivalence of the continuous‐time and discrete‐time experiments is proved by a construction with linear interpolation in one direction and local means for the other. The new estimator outperforms earlier non‐parametric methods in the literature for the considered model. We investigate its finite sample size characteristics in simulations and draw a comparison between various proposed methods.     

Interdependency among addictive behaviours and time/risk preferences: Discrete choice model analysis of smoking, drinking, and gambling

This paper simultaneously measures the rate of time preference and the coefficient of risk aversion, as well as investigates the interdependencies of four addictive behaviours: smoking, drinking, pachinko (a popular Japanese form of pinball gambling), and horse betting among a sample of the Japanese population. We reach two main conclusions. First, there are significant interdependencies among the four addictive behaviours, in particular between smoking and drinking and between gambling on pachinko and the horses. Second, we conclude that the higher the time preference rate and the lower the risk aversion coefficient becomes, the more likely individuals smoke, drink frequently, and gamble on pachinko and the horses.     

Relative Curvature Measure for Heteroscedastic or Non Normal Nonlinear Regression

The Bates–Watts relative curvature measure can assess the validity of the linearized approximation in nonlinear regression models. However, it is developed based on an ordinary nonlinear regression in which the observation is assumed to be homoscedastically and normally distributed. In this article, we extend the original Bates–Watts relative curvature measure to one that can be applicable to nonlinear regression with heteroscedastic or non normal data, based on the transformation-both-sides (TBS) approach. In pharmacokinetic models, a diagnostic use of their measures is illustrated. By means of a simulation experiment, the performance of the relative curvature measure for the TBS approach is evaluated.     

Social norms, inequality and child labor

This paper theoretically analyzes a situation wherein adults’ decisions on child labor are affected not only by materialistic utility but also by a social norm against child labor. The adult thus faces a tradeoff; on the one hand, household income rises if she sends her child to work. On the other hand, the adult suffers disutility from violating the social norm in so doing. We also suppose that the extent of disutility falls as more other adults have their children work. We then explore how the total amount of child labor in an economy changes as adults’ labor efficiencies rise or become more unequal. Our analysis reveals that a more equal distribution or rises in adults’ labor efficiency help decrease child labor only under certain conditions.     

Returns to scale vs. damages to scale in data envelopment analysis: An impact of U.S. clean air act on coal-fired power plants

This study proposes a use of Data Envelopment Analysis (DEA) to measure Returns to Scale (RTS) of US coal-fired power plants. The power plants produce not only desirable outputs (e.g., electricity) but also undesirable outputs (e.g., CO₂ and NO_x) as a result of their plant operations. Therefore, the proposed use of DEA also measures a new concept, or “DTS: Damages to Scale” (corresponding to RTS for undesirable outputs). Both scale measures discussed in this study are a quick-and-easy approach for assessing RTS and DTS, but not an exact method, because it does not consider a direct linkage between the two measures. This study applies the proposed approach to examine the legal validity of U.S. Clean Air Act (CAA). We find that the CAA has been legally effective and influential on the operation of coal-fired power plants in the United States because their plant operations belong to increasing RTS on a desirable output and increasing DTS on three undesirable outputs. The increasing DTS indicates a need for managerial improvement and/or engineering innovation such as advanced clean coal technology. This empirical result implies that U.S. federal and state governments need to expand the legal scope of CAA to the emission control of CO₂ because the current CAA excludes the regulation on CO₂ emission that is now considered as a main source of the global warming and climate change.     

李煜词梦意象探析

现存词仅有30余首的南唐后主李煜的词中,梦的意象在其词的意象群中占了主体地位。身为帝王却生在词林的李后主由于有着独特的身世、遭遇与生平变故,形成了独特的气质和情感。由于梦有着其独特的心理特征,李煜选择了梦的意象来抒发自己的情感。梦的意象的成功创造,使李煜词的艺术成就更为突出。     

中国利用BOT法律问题的思考

BOT是目前国际上流行的投资合作方式,日益受到我国政府的重视,并将成为今后我国引进外资投资于基础设施建设的重要方式.但是,我国现有的法律法规都没有对它做出具体规定,调整BOT投资方式的立法仍不健全,尚未形成BOT项目实施的法律环境,有的法律规范甚至与BOT投资方式相抵触,各地在实际运作中仍会遇到许多法律障碍,不利于BOT项目实施和发展.如何建立和完善我国BOT投资方式的制度与立法已成为当务之急.