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31.
城市用地的紧张促使高层建筑越来越多,而高层建筑的给水和消防对住户而言越来越重要,因此在设计中应摆脱以往小高层和多层的固有设计思路和方法。文章从实际案例出发,简述在高层公寓楼给水和消防设计中应注意的问题。  相似文献   
32.
This paper is concerned with the search for locally optimal designs when the observations of the response variable arise from a weighted distribution in the exponential family. Locally optimal designs are derived for regression models in which the response follows a weighted version of Normal, Gamma, Inverse Gaussian, Poisson or Binomial distributions. Some conditions are given under which the optimal designs for the weighted and original (non-weighted) distributions are the same. An efficiency study is performed to find out the behavior of the D-optimal designs for the original distribution when they are used to estimate models with weighted distributions.  相似文献   
33.
在传统物理经济中,囿于信息技术水平的限制,跨国企业生产经营活动以固定性、有形性、不易移动为特征,趋向于生产供应方向,且销售、市场等需求因素只是消极地提供单一消费市场,对于企业价值创造与营业利润的实现影响甚微.对此,贯彻以“以供应为基础”理论的功能独立实体法尚且能在居民国、来源国间合理划分常设机构的可归属利润.然而,经济...  相似文献   
34.
The paper proposes a framework for modelling cointegration in fractionally integrated processes, and considers methods for testing the existence of cointegrating relationships using the parametric bootstrap. In these procedures, ARFIMA models are fitted to the data, and the estimates used to simulate the null hypothesis of non-cointegration in a vector autoregressive modelling framework. The simulations are used to estimate p-values for alternative regression-based test statistics, including the F goodness-of-fit statistic, the Durbin–Watson statistic and estimates of the residual d. The bootstrap distributions are economical to compute, being conditioned on the actual sample values of all but the dependent variable in the regression. The procedures are easily adapted to test stronger null hypotheses, such as statistical independence. The tests are not in general asymptotically pivotal, but implemented by the bootstrap, are shown to be consistent against alternatives with both stationary and nonstationary cointegrating residuals. As an example, the tests are applied to the series for UK consumption and disposable income. The power properties of the tests are studied by simulations of artificial cointegrating relationships based on the sample data. The F test performs better in these experiments than the residual-based tests, although the Durbin–Watson in turn dominates the test based on the residual d.  相似文献   
35.
A nonlinear long memory model, with an application to US unemployment   总被引:1,自引:0,他引:1  
Two important empirical features of US unemployment are that shocks to the series seem rather persistent and that it seems to rise faster during recessions than that it falls during expansions. To jointly capture these features of long memory and nonlinearity, we put forward a new time series model and evaluate its empirical performance. We find that the model describes the data rather well and that it outperforms related competitive models on various measures of fit.  相似文献   
36.
Changing demographics, growing real incomes, and friendly tax laws underlie the continuing growth in demand for recreational real estate in the US. The market for recreational property has undergone a major transformation over the past decades, with the refinement and deepening of markets for partial property ownership vehicles. This paper represents the first to analyze the factors underlying the demand for partial ownership interests. It develops a theory of partial ownership demand that focuses on the roles of familiarity and location-specific human capital in mediating the consumption uncertainty associated with particular recreation locations. Using private data from a survey of partial ownership participants, the empirical analysis yields results consistent with the theory: factors associated with greater site-specific recreation price, like distance between the primary residence and the recreation site and frequency of visits per week, reduce the share of ownership demanded, while factors associated with lower consumption risk tend to increase the share of ownership demanded.
Carolyn A. DehringEmail:
  相似文献   
37.
假设利率为分数维随机利率,外汇汇率服从分数跳一扩散过程,并且波动率为常数,期望收益率为时间的非随机函数,本文利用保险精算方法,得出了看涨、看跌外汇欧武期权的一般定价公式,并建立了平价公式。  相似文献   
38.
The collection of longitudinal data over the full model time scope is often an appropriate way to estimate the dynamic state space model with time-varying parameters. Nevertheless, in many situations it is possible and preferable to collect and combine data from independent groups of subjects, each covering a shorter interval than the full dynamic model. Several quasi-longitudinal designs are discussed: overlapping designs (overlapping cohort design OCD and overlapping samples design OSD) as well as nonoverlapping designs up to the exclusively cross-sectional design. The use of the structural equation modeling (SEM) program Mx and continuous time state space modeling is recommended. Finally, a number of the quasi-longitudinal designs is empirically evaluated, comparing the results with those of the full-longitudinal design.  相似文献   
39.
李春梅 《价值工程》2010,29(8):11-12
大学计算机语言教材中解决阶乘(n!)问题,都是通过循环来实现;本文提出用Stirling近似公式改进传统的阶乘(n!)问题,简化了程序,加快了速度,节省了空间。  相似文献   
40.
Screening designs are useful for situations where a large number of factors are examined but only a few, k, of them are expected to be important. Traditionally orthogonal arrays such as Hadamard matrices and Plackett Burman designs have been studied for this purpose. It is therefore of practical interest for a given k to know all the classes of inequivalent projections of the design into the k dimensions that have certain statistical properties. In this paper we present 15 inequivalent Hadamard matrices of order n=32 constructed from circulant cores. We study their projection properties using several well-known statistical criteria and we provide minimum generalized aberration 2 level designs with 32 runs and up to seven factors that are embedded into these Hadamard matrices. A concept of generalized projectivity and design selection of such designs is also discussed.AMS Subject Classification: Primary 62K15, Secondary 05B20  相似文献   
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