Cost-constrained measures of environmental efficiency: a material balance approach

Joint cost-environmental efficiency analysis based on the material balance principle (MBP) has an important short-coming, in that the measures of allocative efficiency it produces do not fully integrate environmental and economic outcomes. Their limitation lies in their failure to take into account some decision-making units (DMU) use a combination of inputs that is more environmentally-harmful than that of the least-cost unit, or, more rarely, more costly than that of the least-polluting unit. Input substitution can therefore bring both environmental and economic benefits. This paper develops a method for differentiating between environmental allocative efficiency gains that involve an economic trade-off and those that do not. Drawing insight from the literature on multi-criteria analysis, we extend the MBP approach to new measures of cost-constrained environmental efficiency using data envelopment analysis (DEA). The proposed approach is illustrated by an application geared to assessing the efficiency of a sample of greenhouse horticultural production units in Almeria, Spain. The results for this case show that it is possible to increase environmental allocative efficiency by up to 34 % on average without incurring additional costs

INVESTIGATION OF THE ROLE OF SERVICE LEVEL AGREEMENTS IN WEB SERVICE QUALITY

Context/Background: Use of Service Level Agreements (SLAs) is crucial to provide the value added services to consumers to achieve their requirements successfully. SLAs also ensure the expected Quality of Service to consumers. Aim: This study investigates how efficient structural representation and management of SLAs can help to ensure the Quality of Service (QoS) in Web services during Web service composition. Method: Existing specifications and structures for SLAs for Web services do not fully formalize and provide support for different automatic and dynamic behavioral aspects needed for QoS calculation. This study addresses the issues on how to formalize and document the structures of SLAs for better service utilization and improved QoS results. The Service Oriented Architecture (SOA) is extended in this study with addition of an SLAAgent, which helps to automate the QoS calculation using Fuzzy Inference Systems, service discovery, service selection, SLA monitoring and management during service composition with the help of structured SLA documents. Results: The proposed framework improves the ways of how to structure, manage and monitor SLAs during Web service composition to achieve the better Quality of Service effectively and efficiently. Conclusions: To deal with different types of computational requirements the automation of SLAs is a challenge during Web service composition. This study shows the significance of the SLAs for better QoS during composition of services in SOA

Nonparametric efficiency and productivity change measurement of banks with corporate social responsibilities : the case for Ghana

This thesis has twofold objectives. The first is to develop a framework based on the existing theory and method of Data Envelopment Analysis (DEA) for measuring performance of financial firms that have the dual goals of profit maximisation and Corporate Social Responsibilities (CSRs). The second is to examine the impact of banking regulatory reforms including bank ownership, specialisation, and capitalisation types on the average efficiency and frontier differences of banking subgroups. The objectives are achieved using the standard DEA, the metafrontier analysis and the global frontier differences (GFD). DEA can handle multidimensional inputs and outputs without specifying specific functional forms. CSR is conceptually justified and modelled as an additional output into the banking intermediation approach. Two DEA models, one with CSR and another without CSR are measured and compared. Parametric and nonparametric tests and regressions are utilised to support, empirically, the relevance of CSR in bank performance evaluation. Do foreign banks outperform private-domestic and state banks? Should banks diversify their products or focus in narrow range of products and services? Are listed banks more efficient than non-listed banks? The second part of the thesis contributes to the extant literature by answering these questions using the metafrontier analysis and the GFD to provide new evidence on the effect that the entry of foreign and private-domestic banks, universal banking and listing of banks on the stock market, have on bank performance. Banks are segmented into groups based on their bank-specific attributes and their average efficiencies and bestpractice differences compared. Relevant policy recommendations are drawn from the analysis for both the banking regulator and bank management. The final methodological contribution extends the GFD by defining a further decomposition of the global frontier shift, into components that indicate whether an observation is situated in a more or less favourable location in the production possibility set. Consequently, a four-factor “Newly-decomposed Malmquist productivity change index” is proposed. The index and its decompositions have potentially interesting policy implications, which are illustrated using the empirical data on Ghanaian banks. The index is in the spirit of the standard Malmquist index but the intuition is that some components can be used to draw conclusions about productivity changes for a whole population of firms whilst others determine whether individual firms are in favourable locations and/or moving towards locations that are more favourable over time. More importantly, arguably, a listed, universal or foreign bank can be located in a favourable position and move towards location that is more favourable by virtue of its bank-specific attributes or by contributing more towards CSR. These factors are explored and policy measures prescribed in the final contribution of the thesis