关键词： 计量模型   设定  

摘要： 本文从几个不同的角度 ,讨论了计量模型的设定问题。首先分析了变量的选择对模型的影响。然后 ,从模型的估计、用途、识别等方面进一步研究了模型的设定。此外还讨论了模型设定的结构问题。

关键词： Yong经济   炼油   石油化工   过程系统   扩产  

摘要： 分析了过程系统在扩产的同时进行能量综合优化的必要性。建立了扩产与能量综合同时优化的经济模型 ,提出了两种扩产情形下扩产与能量综合同时优化的策略 ;给出了应用该策略进行扩产与能量综合同时优化的实际案例 。

关键词： 经济学家   经济预测   理论模式   经济模型   价值观  

关键词： 高等级公路建设   总公司   计量经济模型   劳动生产率   沈阳   生产情况   经济增长   规律   基础   位置  

摘要： 本文结合沈阳高等级公路建设总公司十几年大量的统计资料，建立了沈阳高等级公路建设总公司劳动生产率的计量经济模型。通过对高等级公路建设规律和沈阳高等级公路建设总公司生产情况的系统分析，提出了沈阳高等级公路建设总公司今后应把提高经济效益放在经济增长的基础位置，重点是提高劳动生产率。

关键词： Bombus   central place foraging   energetics   flight range  

摘要： 1. A model is described that evaluates the maximum economic foraging range in central place foragers by using optimality criteria to discriminate between foraging sites at different distances from the forager's central place. 2. The basic model can be varied to suit foragers that optimise either their rate of net energy uptake or their foraging efficiency. 3. The model requires specification of the time and energy budgets of travel and foraging, and of the rewards obtainable at potential foraging sites. 4. The specific case of bumblebees, whose foraging ranges are poorly known, is considered. 5. Numerical solutions of the model for parameter values that represent bumblebees and their forage predict economic foraging ranges exceeding several kilometres. The model demonstrates that economics alone can explain extensive flight ranges in bees.

关键词： PACS   medical economics   model   filmless   benchmark   cost   benefit  

摘要： The purpose of this study was to establish data points (benchmarks) to incorporate into a pro-forma cost analysis model, comparing film-based and filmless modes of operation. Prospective data were collected over a 6-year period at the Baltimore VA Medical Center (BVAMC) immediately before and after implementation of a hospital-wide PACS. These data were in turn compared with local and national VA centers during comparable time periods, to establish reference data between manual film-based (without PACS) and filmless operations (using PACS). Benchmarks utilized for the study felt into 2 broad categories: operational costs and revenues generated. Factors contributing to operational costs include space requirements, equipment, supplies, personnel, and maintenance. Factors contributing to revenues generated included examination volume, modality mix, and reimbursement rates. Collectively, these data points were incorporated into a pro-forma model that allows prospective PACS customers to compare total cost of ownership for film-based and filmless operations de pendent on the unique variables of the respective institution. Copyright (C) 2000 by W.B. Saunders Company.

关键词： growth   business cycles   small open economy   transaction costs in foreign assets   government consumption   transfers  

摘要： In this paper we develop a stochastic dynamic general equilibrium model for a small open economy in the real business cycle modeling tradition. Household preferences depend on private and public consumption and leisure. Production technology depends on public capital. Government finances its investment, consumption and transfer payments by means of a proportional income tax rate. Households buy and sell foreign assets in an international capital market with transaction costs and also receive transfer payments from abroad. We calibrate the model for the Greek economy. The volatility, persistence, and co-movement properties of the business cycle component of the data generated by the model are broadly consistent with the actual behavior of the corresponding actual data. We use the model to investigate the response of major macroeconomic variables to temporary and permanent changes in government policy variables, foreign transfers, and the rate on return of foreign assets. We find that increasing government consumption and domestic transfers financed through distorting taxation lowers capital, labor (in most cases) and output while it increases foreign asset holdings, both in the short and the long run. Increasing government investment financed by distorting taxation eventually increases capital and output and decreases labor. Finally transfers from abroad decrease capital, labor and output, while they increase consumption. (C) 2000 Elsevier Science B.V. All rights reserved. JEL classification. El;E3;E6;F3.

关键词： PROTOTYPE equipment   SMALL business  

摘要： Reports that economy versions of rapid prototyping (RP) devices for use by small businesses have been introduced in Great Britain. Price range of RP machines; Development of the JP5 RP machine for the low-end market; Difference of JP5 from the more expensive models.

关键词： 图书馆   经济模型   文献集合   图书馆经济学  

摘要： 文章从图书馆的文献集合所体现的规模效益、保险效益、时间效益的三种经济效益，论述了图书馆的经济模式。

关键词： 动态模型   动态经济学   误差分量   处理方法  

摘要： 由确定性作用转移到随机作用的形式所产生的误差分量模型的估计方法与常规形式是不完全一样的，特别是对于建立在模型的自回归部分相互作用下的序列相关性之上的随机作用的动态模型更是如此。这里我们不妨考虑干扰项的二阶结构……