Search results for "benchmark"
showing 10 items of 310 documents
Accounting for service quality to customers in the efficiency of water companies: evidence from England and Wales
2015
This paper investigates the role of service quality to customers in the efficiency assessment of water companies in England and Wales. To achieve this, data envelopment analysis techniques are employed to compute the technical efficiency of the water companies following two approaches: (i) traditional assessment based on quantity variables (without the inclusion of service quality variables) and (ii) alternative assessment considering quantity and service quality variables as undesirable outputs. The analysis covers 22 water and sewerage companies and water only companies providing drinking water services. The results indicate that the traditional efficiency assessment reveals a high level …
A hierarchical clustering strategy and its application to proteomic interaction data
2003
We describe a novel strategy of hierarchical clustering analysis, particularly useful to analyze proteomic interaction data. The logic behind this method is to use the information for all interactions among the elements of a set to evaluate the strength of the interaction of each pair of elements. Our procedure allows the characterization of protein complexes starting with partial data and the detection of "promiscuous" proteins that bias the results, generating false positive data. We demonstrate the usefulness of our strategy by analyzing a real case that involves 137 Saccharomyces cerevisiae proteins. Because most functional studies require the evaluation of similar data sets, our method…
Efficient Local Search Limitation Strategies for Vehicle Routing Problems
2008
In this paper we examine five different strategies for limiting the local search neighborhoods in the context of vehicle routing problems. The vehicle routing problem deals with the assignment of a set of transportation orders to a fleet of vehicles, and the sequencing of stops for each vehicle to minimize transportation costs. The examined strategies are applied to three standard neighborhoods and implemented in a recently suggested powerful memetic algorithm. Experimental results on 26 well-known benchmark problems indicate significant speedups of almost 80% without worsening the solution quality. On the contrary, in 12 cases new best solutions were obtained.
Toward solutions for energy efficiency
2020
Abstract The tariff setting for district heating (DH) services is a hard regulatory procedure. This chapter is devoted to development of the simple but sufficiently accurate methodology for fast and objective evaluation of the actual costs of DH to optimize the regulatory process and to set adequate tariffs on heat production and transmission. The developed methodology is based on the data sets of Latvian DH providers, but the methodological principles are applicable in another area too. Investigation of heat production drivers and following simulation revealed the key performance indicators (KPIs): fuel type and price. By usage of intelligent benchmarking data mining methods and mathematic…
<strong>New tool useful for drug discovery validated through benchmark datasets</strong>
2018
Atomic Weighted Vectors (AWVs) are vectors that contain the codified information of molecular structures, which can apply to a set of Aggregation Operators (AOs) to calculate total and local molecular descriptors (MDs). This article presents an exploratory study of a new tool useful for drug discovery using different datasets, such as DRAGON and Sutherland’s datasets, as well as their comparison with other well-known approaches. In order to evaluate the performance of the tool, several statistics and QSAR/QSPR experiments were performed. Variability analyses are used to quantify the information content of the AWVs obtained from the tool, by the way of an information theory-based algorithm. …
SUSTAINABLE URBAN PUBLIC TRANSPORT. A COMPARISON BETWEEN EUROPEAN AND NORTH AFRICAN CITIES
2011
The aim of paper is to carry out a benchmarking analysis among European and North African Cities in order to point out the improvement areas for a Sustainable Urban Public Transport System. The focus is to improve public transport performance, all aspects such as fares, operational effectiveness and attractiveness of the service.
Speeding up the Consensus Clustering methodology for microarray data analysis
2010
Abstract Background The inference of the number of clusters in a dataset, a fundamental problem in Statistics, Data Analysis and Classification, is usually addressed via internal validation measures. The stated problem is quite difficult, in particular for microarrays, since the inferred prediction must be sensible enough to capture the inherent biological structure in a dataset, e.g., functionally related genes. Despite the rich literature present in that area, the identification of an internal validation measure that is both fast and precise has proved to be elusive. In order to partially fill this gap, we propose a speed-up of Consensus (Consensus Clustering), a methodology whose purpose…
Methods of spatial cluster detection in rare childhood cancers: Benchmarking data and results from a simulation study on nephroblastoma
2021
Abstract The potential existence of spatial clusters in childhood cancer incidence is a debated topic. Identification of rare disease clusters in general may help to better understand disease etiology and develop preventive strategies against such entities. The incidence of newly diagnosed childhood malignancies under 15 years of age is 140/1,000,000. In this context, the subgroup of nephroblastoma represents an extremely rare entity with an annual incidence of 7/1,000,000. We evaluated widely used statistical approaches for spatial cluster detection in childhood cancer (Ref. [22] Schundeln et al., 2021, Cancer Epidemiology). For the simulation study, random high risk clusters of 1 to 50 ad…
Community-based Immunization Strategies for Epidemic Control
2014
Understanding the epidemic dynamics, and finding out efficient techniques to control it, is a challenging issue. A lot of research has been done on targeted immunization strategies, exploiting various global network topological properties. However, in practice, information about the global structure of the contact network may not be available. Therefore, immunization strategies that can deal with a limited knowledge of the network structure are required. In this paper, we propose targeted immunization strategies that require information only at the community level. Results of our investigations on the SIR epidemiological model, using a realistic synthetic benchmark with controlled community…
Impact of external costs of unplanned supply interruptions on water company efficiency: Evidence from Chile
2020
Abstract Conventional performance assessments of water companies ignore the external costs due to water supply outages. To overcome this gap, we evaluate the impact of external costs of unplanned supply interruptions on the efficiency of water companies. Two efficiency metrics, internal technical efficiency (ITE), and total technical efficiency (TTE), were estimated based on data envelopment analysis (DEA). The results evidence that the external costs of unplanned water supply interruptions impact, on average, 7.9% of the efficiency of water companies. We also explored the impact of a set of environmental variables on water company efficiency.