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41.
More flexible semiparametric linear‐index regression models are proposed to describe the conditional distribution. Such a model formulation captures varying effects of covariates over the support of a response variable in distribution, offers an alternative perspective on dimension reduction and covers a lot of widely used parametric and semiparameteric regression models. A feasible pseudo likelihood approach, accompanied with a simple and easily implemented algorithm, is further developed for the mixed case with both varying and invariant coefficients. By justifying some theoretical properties on Banach spaces, the uniform consistency and asymptotic Gaussian process of the proposed estimator are also established in this article. In addition, under the monotonicity of distribution in linear‐index, we develop an alternative approach based on maximizing a varying accuracy measure. By virtue of the asymptotic recursion relation for the estimators, some of the achievements in this direction include showing the convergence of the iterative computation procedure and establishing the large sample properties of the resulting estimator. It is noticeable that our theoretical framework is very helpful in constructing confidence bands for the parameters of interest and tests for the hypotheses of various qualitative structures in distribution. Generally, the developed estimation and inference procedures perform quite satisfactorily in the conducted simulations and are demonstrated to be useful in reanalysing data from the Boston house price study and the World Values Survey.  相似文献   
42.
In general cases, to find the exact upper bound on the minimal total cost of the transportation problem with varying demands and supplies is an NP-hard problem. In literature, there are only two approaches with several shortcomings to solve the problem. In this paper, the problem is formulated as a bi-level programming model, and proven to be solvable in a polynomial time if the sum of the lower bounds for all the supplies is no less than the sum of the upper bounds for all the demands; and a heuristic algorithm named TPVDS-A based on genetic algorithm is developed as an efficient and robust solution method of the model. Computational experiments on benchmark and new randomly generated instances show that the TPVDS-A algorithm outperforms the two existing approaches.  相似文献   
43.
Free time, that is, the time that remains at one's own discretion after conducting daily work and personal care activities, has been previously recognized as a 'primary good' and an important welfare resource that provides opportunities for participation in social life and leisure. However, recent years have witnessed an increasing preoccupation with the phenomenon of time poverty, drawing attention to the distribution of free time and its relationship to structural and family circumstances. In this article we propose a novel approach to the measurement of time poverty and document its occurrence amongst British workers. In line with previous literature, a conceptualization of time poverty as a relative lack of free time resources vis-à-vis other members of the community is adopted. However, unlike previous empirical studies, we investigate the differential configuration of time poverty on weekdays and weekend days, alongside indicators of the quality of free time, taking into account insights from theoretical and empirical work within the field of the sociology of time. Our analysis of the 2000 UK Time Use Survey highlights class and gender inequalities that have been missed by previous measurement approaches and demonstrates that, overall, working women experience multiple and more severe free time constraints, which may constitute an additional barrier for their leisure and social participation.  相似文献   
44.
Previous studies find that workers of longer work weeks report more market hours in stylized measure than in time diary, while those of shorter work weeks report fewer hours. Using data from the American Time Use Survey (ATUS) 2003-2007, this paper attempts to explain this dilemma. I argue that market work time is composed of activity time, committed time, and constrained time. Thus, part of the difference found between the two estimates is due to the calculation of the diary estimate. I also argue that the wording of the stylized question is consequential. Some stylized questions (e.g., How many hours per week do you usually work?) might capture the mode, instead of the mean, of work time. Thus, when the distribution of work time is skewed, the mismatch between the two estimates is expected. A sequence-based identification for diary estimate and a non-parametric adjustment for stylized estimate are proposed and empirically examined. The result indicates that both methods significantly reduce the observed gap between the two estimates. I discuss the implications for future time use survey design in the concluding section.  相似文献   
45.
标准金融学与行为金融学的根本分歧是市场是否具有有效性。作为标准金融学基石的有效市场假说的致命缺陷是检验时点有效,即在任何一个时点上证券价格都即时、准确地反映所有信息,这一理想化的约束条件不仅使该理论的应用价值大打折扣,也使其存在着巨大的理论缺陷。行为金融学正是抓住这一点对其提出了质疑和挑战。在推翻标准金融学的理论假设后的行为金融学也没有建立一个比标准金融学更有实际应用性的学说体系,其应用性甚至远远落后于被其否定的以CAPM、APT、OPT等为代表的标准金融学理论。市场有效周期理论认为,市场有效是一个时期而不是一个时点,通过实证研究可以对该理论进行检验。市场有效周期理论的重要价值主要是在解决标准金融学和行为金融学的分歧上实现了重大突破。  相似文献   
46.
《大学语文》作为一门素质教育课程,其重要性已愈来愈显见,但它的重要性到底表现在哪些方面,这却是要加以细致地分析的。《大学语文》在启迪学生的生存智性、拓展学生的认知时空和提高学生的美学素质等方面都有着重要的作用。  相似文献   
47.
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.  相似文献   
48.
介绍了一种新型的变频恒压供水系统.该系统根据供水管网的用水情况,调整水泵投入台数及转速,实行全自动恒压供水,达到高效节能的目的;其水泵用变频器软启动,对电网无冲击,能延长水泵的使用寿命.  相似文献   
49.
In a make-to-order environment, lead time and price can play a crucial role in determining the financial success of a firm. Their importance increases when demand is sensitive to the quoted lead time and price. A model is presented which uses the quoted lead time and price as a mechanism to determine the optimal demand level. The relationships between the model parameters and their impacts on the firm's profit is also analysed. In addition, the effect of the number of job requests, and the mean processing time are examined. Based on the results presented in this paper, there is clear indication that the firm's profit is sensitive to the inventory holding rate, and that the inventory holding cost component is redundant in the presence of a tardiness cost component.  相似文献   
50.
This research examined the effects of a casino’s auditory character on estimates of elapsed time while gambling. More specifically, this study varied whether the sound heard while gambling was ambient casino sound alone or ambient casino sound accompanied by music. The tempo and volume of both the music and ambient sound were varied to manipulate temporal engagement and introspection. One hundred and sixty (males = 91) individuals played slot machines in groups of 5–8, after which they provided estimates of elapsed time. The findings showed that the typical ambient casino auditive environment, which characterizes the majority of gaming venues, promotes understated estimates of elapsed duration of play. In contrast, when music is introduced into the ambient casino environment, it appears to provide a cue of interval from which players can more accurately reconstruct elapsed duration of play. This is particularly the case when the tempo of the music is slow and the volume is high. Moreover, the confidence with which time estimates are held (as reflected by latency of response) is higher in an auditive environment with music than in an environment that is comprised of ambient casino sounds alone. Implications for casino management are discussed.  相似文献   
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