Cost efficiency and scale economies in general dental practices in the US: a non-parametric and parametric analysis of Colorado data

This paper uses both the non-parametric method of data envelopment analysis (DEA) and the econometric method of stochastic frontier analysis (SFA) to study the production technology and cost efficiency of the US dental care industry using practice level data. The American Dental Association 2006 survey data for a number of general dental practices in the state of Colorado in the US are used for the empirical analysis. The findings suggest that the cost efficiency score is between 0.79 and 0.87, on average, and the cost inefficiency is mostly due to allocative rather than technical inefficiency. The optimal output level for a dental practice to fully exploit the economies of scale is estimated to be at $1.68 million. Average cost at this level of output is 50.6 cents for each dollar of gross billing generated. The DEA and SFA approaches provide generally consistent results.     

Technical efficiency and economies of scale in state owned enterprises: The Hellenic telecommunications organisation

In this paper we propose methodologies for assessing the relative efficiency of state owned enterprises that operate under monopolistic conditions. Irrespective of the ownership structure (private or public) monopolistic operation is often given unclear/conflicting operating objectives by their principals or regulators and thus efficiency should be assessed using alternative objectives such as cost, production and revenue. On the methodological side the paper employs parametric functional forms using ordinary least squares and goal programming methods of estimation. A secondary estimation stage was also pursued with the input/output variables of the models being corrected for technical inefficiency. The methodology was applied to examine the technical efficiency and economies of scale of the Hellenic telecommunications organisation over the period 1971–1993.     

A dynamic non-parametric measure of output efficiency

A non-parametric programming model for measuring output efficiency that allows for input allocation over finitely many time periods is introduced in this paper. The model thus generalizes the standard non-parametric efficiency measuring models by adding a dynamic aspect to efficiency gauging.     

Reputation and efficiency: A non-parametric assessment of America’s top-rated MBA programs

Widely publicized reports of fresh MBAs getting multiple job offers with six-figure annual salaries leave a long-lasting general impression about the high quality of selected business schools. While such spectacular achievement in job placement rightly deserves recognition, one should not lose sight of the resources expended in order to accomplish this result. In this study, we employ a measure of Pareto-Koopmans global efficiency to evaluate the efficiency levels of the MBA programs in Business Week’s top-rated list. We compute input- and output-oriented radial and non-radial efficiency measures for comparison. Among three tier groups, the schools from a higher tier group on average are more efficient than those from lower tiers, although variations in efficiency levels do occur within the same tier, which exist over different measures of efficiency.     

Measuring the efficiency of highway maintenance contracting strategies: A bootstrapped non-parametric meta-frontier approach

Highly deteriorated US road infrastructure, major budgetary restrictions and the significant growth in traffic have led to an emerging need for improving performance of highway maintenance practices. Privatizing some portions of road maintenance operations by state Departments of Transportation (DOTs) under the auspices of performance-based contracts has been one of the innovative initiatives in response to such a need. This paper adapts the non-parametric meta-frontier framework to the two-stage bootstrapping technique to develop an analytical approach for evaluating the relative efficiency of two highway maintenance contracting strategies. The first strategy pertains to the 180 miles of Virginia’s Interstate highways maintained by Virginia DOT using traditional maintenance practices. The second strategy pertains to the 250 miles of Virginia’s Interstate highways maintained via a Public Private Partnership using a performance-based maintenance approach. The meta-frontier approach accounts for the heterogeneity that exists among different types of highway maintenance contracts due to different limitations and regulations. The two-stage bootstrapping technique accounts for the large set of uncontrollable factors that affect the highway deterioration processes. The preliminary findings, based on the historical data for the state of Virginia, suggest that road authorities (counties) that have used traditional contracting for transforming the maintenance expenditures into the improvement of the road conditions seem to be more efficient than road authorities that have used the performance-based contracting. This paper recommends that road authorities use hybrid contracting approaches that include best practices of both traditional and performance-based highway maintenance contracting.     

Transport economies of scale and firm location

This paper studies the impact of economies of scale in transportation on a firm’s location decision. We relate the location problem to weighted Fermat problems and ramified optimal transportation problems and analyze how transport technologies affect the firm’s transportation and location choices. It is found that in general when the level of transport economies of scale is high, the firm locates its factory in the interior of the Weber triangle with a branching transport structure. Two examples are constructed to illustrate how interactions between transport technology and production technology would affect the firm’s input purchase and factory location.     

Computing economies of vertical integration,economies of scope and economies of scale using partial frontier nonparametric methods

So far, in the nonparametric literature only full frontier nonparametric methods have been applied to search for economies of scope and scale, particularly the data envelopment analysis method (DEA). However, these methods present some drawbacks that might lead to biased results. This paper proposes a methodology based on more robust partial frontier nonparametric methods to look for scope and scale economies. Through this methodology it is possible to assess the robustness of these economies, and in particular to assess the influence that extreme data or outliers might have on them. The influence of the imposition of convexity on the production set of firms was also investigated. This methodology was applied to the water utilities that operated in Portugal between 2002 and 2008. There is evidence of economies of vertical integration and economies of scale in drinking water supply utilities and in water and wastewater utilities operating mainly in the retail segment. Economies of scale were found in water and wastewater utilities operating exclusively in the wholesale, and in some of these utilities diseconomies of scope were also found. The proposed methodology also allowed us to conclude that the existence of some smaller utilities makes the minimum optimal scales go down.     

Estimating returns to scale using non-parametric deterministic technologies: A new method based on goodness-of-fit

The purpose of this note is to define a new and more general method to obtain qualitative information about returns to scale for individual observations. The traditional methods developed for estimating returns to scale on non-parametric deterministic reference technologies (Data Envelopment Analysis (DEA) models) are reviewed. A new and more general method that is suitable for all reference technologies is provided. Its usefulness is illustrated by considering variations on an existing non-convex production model, known as the Free Disposal Hull (FDH). When different returns to scale assumptions are introduced into the FDH, then previous methods for determining returns to scale do no longer apply.     

Location of slaughterhouses under economies of scale

The facility location problem described in this paper comes from an industrial application in the slaughterhouse industry of Norway. Investigations show that the slaughterhouse industry experiences economies of scale in the production facilities. We examine a location-allocation problem focusing on the location of slaughterhouses, their size and the allocation of animals in the different farming districts to these slaughterhouses. The model is general and has applications within other industries that experience economies of scale.We present an approach based on linearization of the facility costs and Lagrangean relaxation. We also develop a greedy heuristic to find upper bounds. We use the method to solve a problem instance for the Norwegian Meat Co-operative and compare our results to previous results achieved using standard branch-and-bound in commercial software.     

Multiple unit auctions with economies and diseconomies of scale

This paper discusses multiple unit auctions for industrial procurement where the cost structures of suppliers capture economies and diseconomies of scale caused by the nature of the production cost and the opportunity value of suppliers’ capacities. The problem of winner determination and demand allocation is proven to be NP-complete. We propose a binary tree algorithm with bounds (BTB) which efficiently exploits the model’s optimality properties. BTB outperforms general integer optimization software in computational time, especially with existence of substantial economies and diseconomies of scale. The algorithm complexity is linear in demand volume. This property allows for efficient handling of high volume auctions and thus leads to increased benefit for the overall system. Under the assumption of the myopic best response strategies, we investigate the behavior of suppliers and price dynamics for iterative (multiple round) bidding with appropriate allocation and stopping rules. The allocation rules, featured by several tie breakers for multiple optimal solutions to the allocation model in each round, are proposed to induce suppliers’ dominant strategies and to improve the system’s performance.     

A non-parametric test for composite hypotheses in survival analysis

Summary For survival data with several concomitant (regressor) variables a large sample non-parametric procedure is presented which provides significance tests of hypotheses about a subset of the concomitant variables. This non-iterative procedure resembles linear model methodology in simplicity and form. The method is useful to eliminate unimportant concomitant variables prior to estimation of model parameters.     

Product mixes as objects of choice in non-parametric efficiency measurement

Non-radial measures of technical efficiency essentially differ from their radial counterparts in that the product mix of the efficient reference is allowed to be different from the product mix of the evaluated observation. Whereas existing non-radial measures are still based on the product mix of the evaluated, i.e., possibly inefficient observation, we change the perspective and propose a measure based on the mix properties of the efficient reference. The resulting `inverse' measure can be considered as complementary to the Färe–Lovell (or “Russell”) efficiency measure.     

Supply chain design considering economies of scale and transport frequencies

In this paper we consider a 3-echelon, multi-product supply chain design model with economies of scale in transport and warehousing that explicitly takes transport frequencies into consideration. Our model simultaneously optimizes locations and sizes of tank farms, material flows, and transport frequencies within the network. We consider all relevant costs: product cost, transport cost, tank rental cost, tank throughput cost, and inventory cost. The problem is based on a real-life example from a chemical company. We show that considering economies of scale and transport frequencies in the design stage is crucial and failing to do so can lead to substantially higher costs than optimal. We solve a wide variety of problems with branch-and-bound and with the efficient solution heuristics based on iterative linearization techniques we develop. We show that the heuristics are superior to the standard branch-and-bound technique for large problems like the one of the chemical company that motivated our research.     

Aggregation of scale efficiency

In this article we generalize the aggregation theory in efficiency and productivity analysis by deriving solutions to the problem of aggregation of individual scale efficiency measures, primal and dual, into aggregate primal and dual scale efficiency measures of a group (e.g., industry). The new aggregation result is coherent with aggregation framework and solutions that were earlier derived for other related efficiency measures and can be used in practice for estimation of scale efficiency of an industry or other groups of firms within it.     

Analyzing total-factor energy efficiency in Croatian counties: evidence from a non-parametric approach

Central European Journal of Operations Research - Using energy efficiently has become top priority concern which requires an adequate policy reaction bearing in mind both energy conservation and...     

Computation of elasticity and scale effect in technical efficiency analysis of complex systems

Elasticity, the scale effect, and marginal rates are computed in technical efficiency analysis of complex systems by parametric optimization algorithms developed by the authors. It is shown that the scale effect evaluated at the vertices of a polyhedron face does not necessarily produce the scale effect on the entire face. To find the scale effect on a face of the production possibilities set it is sufficient to determine it at a single interior point on that face. The proposed approach is applied to analyze banking activities. Some modeling results are reported. __________ Translated from Nelineinaya Dinamika i Upravlenie, No. 4, pp. 315–340, 2004.