On the flexible functional forms

This note proposes a general structure of the so-called flexible functional forms able to describe direct utility functions. It is obtained by solving the functional equation:

需求不确定性条件下的成本研究

文章分析了需求不确定性带来的成本影响,并且比较两种不同供应链模式的优劣以及对于不确定性的柔性。     

The choice of functional forms for hedonic price equations: Comment

Rosen [13], Freeman [4], Halvorsen and Pollakowski [6], and others have stressed that economic theory does not suggest an appropriate functional form for hedonic price functions.¹ It consequently is reasonable to try several functional forms and utilize the multiple regression equation with the best performance. In this spirit, Halvorsen and Pollakowski [6] recommend using the Box-Cox flexible functional form for hedonic analysis and measuring best performance with a goodness of fit test. The Box-Cox methodology has also been adapted in hedonic studies by Goodman [5], Linneman [10], Blomquist and Worley [1], and Eberts and Gronberg [3].² The Box-Cox is particularly suited for testing functional forms because many familiar forms such as semilog, log linear, and translog are subsets of the flexible Box-Cox permitting nested hypothesis testing.In this note, we illustrate that the formal hypothesis testing advantage of the Box-Cox functional form is purchased at the expense of other important goals. The goal of most hedonic studies is to estimate the prices of the characteristics, to measure the response to changes in the prices, and/or to predict future expenditures. Using a best fit criterion to choose functional forms does not necessarily lead to more accurate estimates of characteristic prices. In fact, the large number of coefficients estimated with the Box-Cox functional form reduces the accuracy of any single coefficient which could lead to poorer estimates of specific prices. Second, because any negative number raised to a noninteger real power is imaginary, the traditional Box-Cox functional form is not suited to any data set containing negative numbers. Third, the Box-Cox functional form may be inappropriate for prediction. Since the mean predicted value of the untransformed dependent variable need not equal the mean of the sample upon which it is estimated, the predicted untransformed variable (housing value) will be biased. The predicted untransformed dependent variable may also be imaginary. Fourth, the nonlinear transformation results in complex estimates of slopes and elasticities which are often too cumbersome to use properly. We discuss each of these drawbacks and quantify them when possible in the remainder of this note.     

The industrial and commercial demand for electricity under time-of-use pricing

In this paper we have developed and estimated the demand for electricity by an industrial (commercial) firm subject to time-of-use (TOU) pricing of electric power. In the application we use a quadratic production function and directly incorporate into the production process the restrictions that some inputs cannot vary over the day. We show that the TOU structure implies a unique set of parameter restrictions across the demand functions for inputs.     

基于体验视角的医疗消费需求分析

体验经济时代带来了医疗消费环境的变化,文章从体验的视角对医疗消费需求进行分析,体验经济时代医疗消费需求呈现新的特征:情感需求的比重增加、主动参与意识增强、多层次个性化需求显现,现代医院应运用体验营销的新观念,真正从医疗消费者的需求出发,达到医疗消费者的最大满意。     

Preference symmetries,partial differential equations,and functional forms for utility

A discrete symmetry of a preference relation is a mapping from the domain of choice to itself under which preference comparisons are invariant; a continuous symmetry is a one-parameter family of such transformations that includes the identity; and a symmetry field is a vector field whose trajectories generate a continuous symmetry. Any continuous symmetry of a preference relation implies that its representations satisfy a system of PDEs. Conversely the system implies the continuous symmetry if the latter is generated by a field. Moreover, solving the PDEs yields the functional form for utility equivalent to the symmetry. This framework is shown to encompass a variety of representation theorems related to univariate separability, multivariate separability, and homogeneity, including the cases of Cobb–Douglas and CES utility.     

Estimation of a dynamic demand function for gasoline with different schemes of parameter variation

In this article we explore the consumer demand for gasoline within the framework of the household production function model. Working with a time series of regional cross-sections, we find the parameters in the gasoline demand model varying across states. Random coefficient model is utilized to analyze temporal cross-section data.     

Compositional change,aggregation, and dynamic factor demand. Estimates on a panel of manufacturing firms

Most empirical research on investment and dynamic factor demand has used aggregated data. The large number of authors who have cited this as a source of problems strongly suggests possible benefits from analyzing individual firm data. This paper presents an analysis of a panel dataset of US manufacturing firms. Several models, based on cost minimization and a three-factor Cobb–Douglas technology, are developed. The differences concern whether the technology varies across two-digit SIC industries, the presence of fixed adjustment lags, and the determinants of adjustment costs. Identification relies on the rational expectations hypothesis, and estimation on non-linear 3SLS. The estimates indicate that versions with the adjustment lag perform better than others. Conditional elasticities reveal that factor demand responds rapidly to anticipated changes in output and factor prices, a finding consistent with other recent work. It appears that the factor demand of large firms is more price sensitive and less sensitive to output than small firms, consistent with recent work on credit market imperfections. Comparison of the results based on the pooled and the industry varying technologies indicate that the use of aggregate data is indeed a source of problems.     

On the detectability of different forms of interaction in regression models

We consider the ability to detect interaction structure from data in a regression context. We derive an asymptotic power function for a likelihood-based test for interaction in a regression model, with possibly misspecified alternative distribution. This allows a general investigation of different types of interactions which are poorly or well detected via data. Principally we contrast pairwise-interaction models with ‘diffuse interaction models’ as introduced in Gustafson et al. (Stat Med 24:2089–2104, 2005).     

Control charts for health care monitoring under overdispersion

An attractive way to control attribute data from high quality processes is to wait till r ≥ 1 failures have occurred. The choice of r in such negative binomial charts is dictated by how much the failure rate is supposed to change during Out-of-Control. However, these results have been derived for the case of homogeneous data. Especially in health care monitoring, (groups of) patients will often show large heterogeneity. In the present paper we will show how such overdispersion can be taken into account. In practice, typically neither the average failure rate, nor the overdispersion parameter(s), will be known. Hence we shall also derive and analyze the estimated version of the new chart.     

Measuring performance in the presence of stochastic demand for hospital services: an analysis of Belgian general care hospitals

Since demand for hospital services is subject to substantial variability, the relationship between uncertain demand, excess capacity, hospital costs and performance should be investigated thoroughly. In this paper a waiting time indicator to proxy hospital standby capacity is incorporated into a multi-product translog cost function for Belgian general care hospitals. The indicator is derived from queuing theory and improves on the conventionally used (inverse of the) occupancy rate. The multi-product stochastic frontier specification allows calculation of cost elasticities and marginal cost of seven hospital departments, as well as the degree of economies of scale and scope and enables identification of differences in efficiency.

社区医疗企业的经营策略研究

社区医疗经营的好坏关系到广大人民群众的切身利益,同时发展社区医疗存在大量的商机,但是目前许多问题阻碍了社区医疗的进一步发展。文章指出,如何去发掘潜力、发展壮大社区医疗,关键是要有创新的思维,目前社区医疗走与大医院联营或者与大医院直接经营的方式应该是一种值得尝试的途径。     

强化采购管理降低医疗成本

医疗采购是医院管理的一个重要方面,文中分析了目前医院采购供应链中存在的一些问题,提出改变信息流及缩短物流,优化采购供应流程,以达到降低医疗成本,提高医院竞争力。     

Consumers' surplus and the demand for cigarettes

This paper examines the demand for cigarettes in South Africa over a 20-year period from 1970 to 1989. Consumption per capita was found to be significantly determined by price and disposable income per capita; but not by advertising. Price and income elasticities and consumers' surplus were computed from the demand model. The question was raised as to whether or not consumers' surplus should be regarded as having been inferred from a health-hazard-discounted demand schedule. The answer depends on the degree to which smoking decisions are taken with full information or, conversely, are influenced by habit. Given the latter assumption, the consumers' surplus measured for cigarette consumption is nevertheless substantially higher than the estimated health costs of smoking as computed by the Medical Research Council.     

Assessing the potential demand for electric cars

An ordered logit specification for use on ranked individual data is used to analyze survey data on potential consumer demand for electric cars. In many situations in economics and marketing we would like to be able to forecast consumer demands for goods which have not yet appeared in actual markets. By defining goods as a bundle of underlying attributes, we can use discrete choice models to estimate consumer evaluations. Then new good demand is forecast by use of the estimated coefficients to compare consumer evaluation of the new good to existing choices. When ranked individual data are available, we can estimate separate coefficients for each individual rather than assuming identical coefficients as is usual with logit models. Our results indicate considerable dispersion in individual coefficients. This finding can have important implications for new product analysis.     

论现行体制下国家审计法治的基本要求

国家审计机关的职权源于法律,无法律即无国家审计监督制度,无法律即无国家审计监督行为。这一根本要求与“有限政府权力”和“职权法定”的行政法治原则相一致。如果要推行国家审计法治,严格依法审计监督,国家审计机关的工作应满足以下几项基本要求:国家审计机关起草的审计法律,或制定的审计部门规章、审计准则和其他审计职业规范要合法。国家审计机关起草的审计法律应符合国家宪法。国家审计机关制定的审计部门规章、审计准则、审计职业道德等下位规章和规范不应与上位法律相矛盾。这是宪法优先原则和法律优先原则的体现,也是国家审计法治…     

基于先进技术形式下我国绿色物流的思考

文章就我国绿色物流与国际先进国家物流的差距进行了分析,提出应加强物流绿色化的政策和理论体系建立的呼声。