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151.
This article examines the effects of excess capacity on the production cost and technical inefficiency of hotels and restaurants in Norway. The dataset includes a daily unbalanced panel of 94 hotels and restaurants from 2003 to 2014. To accommodate inefficiency, we use an input distance function (IDF). Inefficiency in the IDF means that if inputs are overused by k% then production cost is also increased by k%. We also allow inefficiency to differ across locations and regions by using them as determinants. The results indicate that excess capacity considerably affects the cost and increases inefficiency. The marginal effect on cost increases with excess capacity, but the effect on inefficiency sets in when it exceeds 50 percent. Furthermore, we find less overuse of inputs by firms in small metro towns and the Northern region causing them to be more efficient [except for the Southern and Western regions] than their counterparts.  相似文献   
152.
We develop an algorithm that forecasts cascading events, by employing a Green’s function scheme on the basis of the self-exciting point process model. This method is applied to open data of 10 types of crimes happened in Chicago. It shows a good prediction accuracy superior to or comparable to the standard methods which are the expectation–maximization method and prospective hotspot maps method. We find a cascade influence of the crimes that has a long-time, logarithmic tail; this result is consistent with an earlier study on burglaries. This long-tail feature cannot be reproduced by the other standard methods. In addition, a merit of the Green’s function method is the low computational cost in the case of high density of events and/or large amount of the training data.  相似文献   
153.
Shabbir Ahmad 《Applied economics》2020,52(36):3976-3997
ABSTRACT

This paper contributes to the productivity literature by demonstrating novel econometric methods to estimate input-mix efficiency (IME) in a parametric framework. Input-mix efficiency is defined as the potential improvement in productivity with change in input mix. Any change in input-mix (e.g., land to labou r ratio) will result in change in productivity. The advantage of this approach is that it does not require data on input prices to estimate the mix efficiency levels. A nonlinear input-aggregator function (e.g., Constant Elasticity of Substitution) is used to derive an expression for input-mix efficiency. Bayesian stochastic frontier is estimated for obtaining mix efficiency using US state-level agricultural data for the period 1960–2004. Significant variation in input-mix efficiency is noted across the states and regions, attributable to diverse topographic and geographic conditions. Furthermore, comparisons of allocative and mix efficiencies provide insightful policy implications. The production incentives such as taxes and subsidies could help farmers in adjusting their input mix in response to changes in input prices, which can affect the US agricultural productivity significantly. The proposed methodology can be extended by i) using flexible functional forms; ii) introducing various time- and region-varying input aggregators; and iii) defining more sophisticated weights for input aggregators.  相似文献   
154.
This study empirically examines the relation between institutional distance (ID) and Turkey’s outward foreign direct investment (TODI). The empirical results use panel data from 2002 to 2016 to show that TODI is attracted to countries with better institutional quality. We also find that host country political stability, government effectiveness, control of corruption, and rule of law attract TODI. We also document that TODI is positively related to cultural distance (CD) and ID is not moderated by CD.  相似文献   
155.
We review a rich class of point process models, Cox point processes, and illustrate the necessity of more than one observation (point patterns) in performing parameter estimation. Furthermore, we introduce a new Cox point process model by treating the intensity function of the underlying Poisson point process as a random mixture of normal components. The behaviour and performance of the new model are compared with those of popular Cox point process models. The new model is exemplified with an application that involves a single point pattern corresponding to earthquake events in California, USA.  相似文献   
156.
Based on construal level theory, this research addresses the moderating role of an individual's psychological distance towards a disease in the effectiveness of advertising messages framed by two distinctive construal level terms (high-level and low-level). In Experiment 1, two different disease types (bronchitis/distant disease vs. influenza/proximal disease) were featured, with the result that an advertisement with high-level construal terms was more persuasive for a psychologically distant disease (bronchitis) than for a psychologically proximal disease (flu). The reverse was true for an ad framed with low-level construal terms. To replicate Experiment 1 and further test the hypothesis, in Experiment 2, the perceived distance individuals have towards one disease (cancer) was measured and used as independent variable. Consistent with the results from Experiment 1, the low-level construal messages were more effective under the psychologically close condition than the psychologically distant condition. Reverse was true for the high-level construal messages.  相似文献   
157.
Finite mixtures offer a rich class of distributions for modelling of a variety of random phenomena in numerous fields of study. Using the sample interpoint distances (IPDs), we propose the IPD‐test statistic for testing the hypothesis of homogeneity of mixture of multivariate power series distribution or multivariate normal distribution. We derive the distribution of the IPDs that are drawn from a finite mixture of the multivariate power series distribution and multivariate normal distribution. Based on the empirical distribution of the IPDs, we construct a bootstrap test of homogeneity for other multivariate finite mixture models. The IPD test is applied to mixture models for matrix‐valued distributions and a test of homogeneity for Wishart mixture is presented. Numerical comparisons show that IPD test has accurate type I errors and is more powerful in most multivariate cases than the expectation–maximization (EM) test and modified likelihood ratio test.  相似文献   
158.
庞军 《价值工程》2015,(14):183-185
由于500ml左右矿泉水瓶瓶口具有统一的螺纹规格,其次,瓶体的容量也具有接近统一的标准,这就为矿泉水瓶再生设计的开发提供了必要的前提。市场上关于矿泉水瓶的再生设计多利用矿泉水瓶作为盛水的容器,而没有继续探讨其盛放小型垃圾(瓜子壳,纸屑,铅笔屑等)的功能。本文以绿色设计中延长产品生命周期的理念为原则,以联想法、模仿法及组合法等产品设计方法为指导,推出一款全新的使用矿泉水瓶衍生功能的产品,并着重介绍在本设计进行的过程中得出的新的设计方法:系统化条件下的功能衍生法。通过这款设计来说明现有产品衍生出新的功能的可行性,并总结一定的设计经验与设计方法,为以后进行相关设计奠定理论和方法基础。  相似文献   
159.
张超伦  戴路  翟辉 《价值工程》2015,(13):232-233
沙溪的传统白族民居保存较好,数量庞大,既有大理白族民居的特点又有沙溪的地方特征。民居建筑材料为土、木、石。沙溪地区太阳辐射剧烈,冬季严寒,为提升室内舒适度,需要一些现代建筑技术手段来解决这些问题。随着社会的发展,为了适应现代化的生产方式,民居的功能空间发生了改变,并且伴着旅游开发,商业也作为一个不可缺少的因素融入到了沙溪民居中。  相似文献   
160.
气藏动态储量是指参与渗流的地下气体地质储量,计算动储量常采用物质平衡法,但是对于难以获得平均地层压力的致密气藏不适用。本文介绍了利用气井长时间生产数据计算动态储量的方法,并研究采用叠加时间函数(Super-t)分析变产量修正时间,使计算结果更加精确;同时应用该方法对苏东南区致密砂岩气藏部分气井进行单井动态储量计算,为该区动储量估算提供借鉴。  相似文献   
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