A Varying Parameters Approach to Constructing House Price Indexes

Conventional housing price index models assume interperiodparameter stability and typically employ either repeat sales or hedonic methodologies. This paper introduces a method of index construction that combines multiple sales observations with single sale transactions while permitting characteristics prices from hedonic regressions to vary over time. A test for interperiod parameter stability is provided. Each period's data are arranged by location and repeat sales are matched by rows. This construction allows greater use of sample information and acknowledges the unique contribution of repeat sales to the estimation process. It also produces intertemporal error correlations that can be beneficially exploited by the seemingly unrelated regressions (SUH) technique. The paper also demonstrates a significance test for error correlation and discusses the treatment of unequal numbers of observations among index periods.     

Employment,schooling and productivity growth

Summary This paper presents an empirical analysis of labour demand and labour productivity growth in The Netherlands. Assuming an aggregate production function with as factors capital and 3 types of labour, distinguished by educational attainment, cost minimization leads to a set of 3 labour demand relations to be estimated on time series data. Using the estimates and the implied elasticities, aggregate labour productivity growth is decomposed into factor substitution, autonomous factors, labour time shortening, economies of scale, utilization rates and the increased educational level of the working population. The contributions of substitution, utilization rates and education appear to be substantial, notably in the seventies.

List of symbols

Variables a _i Efficiency index of skill leveli - C production - h _i working-time index for skill leveli - g _i steady-state growth rate of skill leveli - K capital stock - L _i employment volume of skill leveli - L _i ^* desired level of labour skill leveli - p output price - p ^* desired output price - s _i ^* long-run static labour shares in the production value - p _k rental price of capital - P index of total factor productivity - P _l index of labour productivity - u _i utilization rate of skill leveli - u _k utilization rate of capital - w _i wage rate for skill leveli - y production volume - y _yij Hicks partial elasticities of complementarity - _i steady-state cost share of skill leveli - _k Bk steady-state cost share of capital - _f lf highest level price index in cost function nesting - _g 4 intermediate level price index in cost function nesting - _h 4 lowest level price index in cost function nesting - _i steady-state relative wage share of skill leveli - _ij Allen partial elasticities of substitution Parameters d _i l adjustment speed of skill leveli - d _p price adjustment speed - M mark-up on marginal costs - scale elasticity of production - _i distribution parameter in cost function,i = 3, g - _i distribution parameter in cost function,i = k, h - _i distribution parameter in cost function,i =1, 2 - _i autonomous labour productivity growth for skill leveli - _i cost share of skill level in base year - _f production cost index in base year - _i hours elasticity in labour efficiency index - group elasticity of substitution betweenL ₃ and (K, (L ₁,L ₂)) - _g Og group elasticity of substitution betweenK and (L ₁,L ₂) - _h 6h group elasticity of substitution betweenL ₁ andL ₂ We would like to thank B. Downey, G.M.M. Gelauff, A. Nieuwenhuis, J.M.M. Ritzen, J.C. Siebrand and an unknown referee for helpful comments on earlier drafts.     

Boundedly complete families which are not complete

Summary Completeness of a family of probability distributions implies its bounded completeness but not conversely. An example of a family which is boundedly complete but not complete was presented by Lehmann and Scheffe [5]. This appears to be the only such example quoted in the statistical literature. The purpose of this note is to provide further examples of this type. It is shown that any given family of power series distributions can be used to construct a class containing infinitely many boundedly complete, but not complete, families. Furthermore, it is shown that the family of continuous distributions , is boundedly complete, but not complete, whereU denotes the uniform distribution on [a, b] and {P _ϑ,ϑ ∈ IR}, is a translation family generated by a distributionP ₀ with mean value zero, which is continuous with respect to the Lebesgue measure.     

A generalized maximum likelihood characterization of the normal distribution

LetP be a probability measure on ℝ andI _x be the set of alln-dimensional rectangles containingx. If for allx ∈ ℝⁿ and θ ∈ ℝ the inequality holds,P is a normal distributioin with mean 0 or the unit mass at 0. The result generalizes Teicher’s (1961) maximum likelihood characterization of the normal density to a characterization ofN(0, σ²) amongall distributions (including those without density). The m.l. principle used is that of Scholz (1980).     

Purchasing practices in a hospital environment: an ethical analysis

The critical state of the hospital industry, as previously described, generates a difficult decision environment for the materiel manager and those in the purchasing function. The unique life- and death circumstances of hospitals impose a further onus on those who manage them. In the name of saving lives, they can find a convenient excuse to disregard all moral principles, forgetting the Socratic dictum "it is not enough that one lives, but that one lives well." Without the moral "right stuff," they can easily give in to the seductions of momentary gains and glory through ethical short-cuts. There is wisdom and consolation in the words that "nice guys may appear to finish last, but usually they're running in a different race." Studies have established a direct relationship between corporate excellence and ethical values. The reality of competition in the hospital industry dictates that the integration of ethics into the life of the organization should happen by design and not by accident. This is what is meant by strategy. If hospitals would strive for excellence to survive and grow, they should have a strategy with a mission statement that also embodies its moral values and moral agenda. Such an approach does not guarantee that an organization will become immune to moral contamination, but it does provide an antidote.     

Economic humidity control: an alternative to reheat

Heat pipe technology will have a significant impact on the power consumption of many manufacturing industries, the installation costs of new or replacement air conditioning systems, and on electric utility peak demands.     

Maximizing purchase decision factors other than price

Assessing and acquiring technology does not have to be chaotic, driven solely by price, clinical preference, and emotion. With the tools available, it can be distilled to a process of organized common sense, which results in maximum flexibility for the user and allows materiel managers to procure the best, most cost-effective equipment for the hospital.