Ioannis E. Tsolas

Sustainable construction and drivers of change in Greece: a Delphi study

During the last decade, sustainable development issues have been gradually adopted in Greeces construction industry, changing the traditional methods and technology. The aim of this investigation is to identify potential drivers of change, to position them properly in the wider context of sustainable construction and to outline the progress to be expected in the coming decade. The methodological framework used is a Delphi technique based on a questionnaire of 20 experts (consultant engineers, construction managers and contractors). The results show that the most important influences on sustainable construction in Greece are energy conservation measures, resource conservation strategies and waste reduction. In terms of the initiatives expected in the coming decade, energy conservation measures, waste reduction measures, as well as product innovation and certification are expected to rank high. In conclusion, the results are consistent with those of previous researchers showing significant trends towards land use, energy, and resource conservation.

Modeling bank branch profitability and effectiveness by means of DEA

Purpose – The purpose of this paper is to provide a framework for evaluating the overall performance of bank branches in terms of profitability efficiency and effectiveness.Design/methodology/approach – Applying a two‐stage DEA model to a sample of bank branches of a large commercial bank in Greece this study disaggregates overall performance into profitability efficiency and effectiveness.Findings – The results indicate that superior insights can be obtained by employing the proposed two‐stage DEA model compared to the outcomes from the analysis based on selected key performance indicators (KPIs). Some relations between profitability efficiency and effectiveness are also investigated.Originality/value – The study highlights the importance of encouraging increased profitability and efficiency throughout the branch network of the commercial bank under study.

Modelling profitability and effectiveness of Greek-listed construction firms: an integrated DEA and ratio analysis

Existing research on construction performance measurement is dominated by project level studies, and the firm stakeholders require the development of models that compare performance in terms of efficiency. A new framework that integrates data envelopment analysis (DEA) and ratio analysis using a two-step approach is described to evaluate performance in terms of profitability and effectiveness of a sample of construction firms listed on the Athens Exchange. In the first step, profitability and effectiveness are assessed by employing DEA and by using the profit margin (i.e. income-to-sales ratio), respectively. In the second step, a Tobit and an ordinary least squares model are used in order to identify the drivers of profitability efficiency and effectiveness, respectively. Results do point out positive links between profitability efficiency and effectiveness. Profitability inefficiency can be explained by the size and expenses-to-total revenue ratio, whereas effectiveness can be explained only by the latter explanatory variable. The research framework may benefit not only Greek construction firms, but also firms in other countries to quantify their performance and improve their competitive advantages.

Modeling Profitability and Stock Market Performance of Listed Construction Firms on the Athens Exchange: Two-Stage DEA Approach

AbstractThe purpose of this paper is to evaluate the performance of a sample of nineteen construction firms listed on the Athens Exchange by applying a two-step procedure. In the first step, data envelopment analysis (DEA) is used to model performance in two dimensions: profitability efficiency and efficiency in the market value-generating process. This allows the independent identification of the most efficient level of input in minimizing resources and the most efficient level of output in maximizing market value, various benchmarks, and the local returns to scale patterns of the firms of the sample in both performance dimensions. Moreover, it is possible to examine whether a correlation exists between the performance efficiency scores. In the second step, regression models are used to identify the drivers of performance. Performance inefficiency is uncovered in both dimensions, but the real problem of inefficiency of the sampled firms is the lower level of performance in the market value-generating pro...

Bank branch efficiency evaluation by means of least absolute deviations and DEA

Purpose - The purpose of this paper is to assess the efficiency of individual branches of a large Greek bank through the application of both goal programming (GP) and data envelopment analysis (DEA). Design/methodology/approach - The paper employs a particular least absolute deviations (LAD) technique (i.e. a special case of GP/constrained regression) and DEA as two performance measurement methods. The performance evaluation by means of GP is assessed utilizing two alternative conceptual (parametric functional form-loglinear) models: one focusing on transaction and one on production efficiency. The DEA assessment using the transaction efficiency model is performed under the specifications of constant or variable returns to scale. Findings - The two methods do provide confirmation of each others findings. The results support the main claim that there is a strong relationship between the rankings obtained by GP and DEA. Moreover, the GP results indicate that there is a relationship between bank branch transaction and production efficiency. Practical implications - The results may be of interest to stakeholder groups such as bank shareholders, managers, and regulatory authorities. Originality/value - The paper is believed to be the first to examine the application of GP and DEA to measure the efficient use of resources of bank branches in Greece in terms of location (urban-rural).

Bank branch‐level DEA to assess overall efficiency

Purpose – The purpose of the research presented in this paper is to provide a new approach related to the definition of variables in disaggregating branch expenses and income for evaluating the overall technical efficiency of bank branches by means of data envelopment analysis (DEA).Design/methodology/approach – By applying an input minimization DEA model to a sample of bank branches of a large commercial bank in Greece, this study identifies pure technical and scale inefficiencies, efficiency and size relationship and returns to scale patterns. Moreover, it explores target setting strategies for inefficient branches.Findings – Results indicate that branch size has an important influence on efficiency and that superior insights can be obtained by pure technical efficiency (PTE) and scale efficiency (SE), as constituent components of global technical efficiency (TE) than the information obtained from the analysis based on selected key performance indicators (KPIs) used by the bank under study.Research limi...

Assessing power stations performance using a DEA‐bootstrap approach

Purpose – The purpose of this paper is to assess the performance of Greek fossil fuel‐fired power stations employing a data envelopment analysis (DEA) model combined with bootstrapping.Design/methodology/approach – DEA is used to derive aggregate performance indicators using data on inputs and desirable and undesirable outputs for a sample of fossil fuel‐fired power stations. The statistical significance of the derived aggregate performance indicators is assessed via the bootstrapping approach.Findings – The results suggest that the power stations in the sample are considerably more inefficient than revealed by the initial point estimates of inefficiency. Moreover, the non‐lignite‐fired stations of the sample are on an average more efficient than the lignite‐fired stations.Research limitations/implications – DEA represents a useful framework for exploring the current state to derive aggregate performance indicators of power stations, and moreover, the statistical properties of these metrics can be assesse...

Construction Project Monitoring by Means of RAM-Based Composite Indicators

This paper aims to assess the performance of a sample of completed building projects in Oregon by employing the range-adjusted measure, a slack-based data envelopment analysis (DEA) model. In the first stage of analysis, project efficiency ratings (ie composite indicators) are derived using selected single performance indicators in a no-output model; whereas in the second stage, censored Tobit regression is employed to model the efficiency ratings. The results indicate that only four out of the 50 sample projects are efficient within the DEA context. Moreover, there is not much evidence for systematic effects of project size on DEA efficiency rating.

Green exchange-traded fund performance appraisal using slacks-based DEA models

This paper appraises the performance of a sample of green exchange-traded funds (ETFs) using two types of data envelopment analysis (DEA) metrics. The first type is based on slacks-based DEA models, namely, the range-adjusted measure (RAM) and its variant the RAM-BCC model; the second type is based on a common set of weights of RAM. The appraisal is performed under the assumption that there are value stocks on the green equity market and the potential investors prefer ETFs that put emphasis on value stocks. In the first stage of the analysis, ETF efficiency ratings are derived, whereas in the second stage, ordinary least squares, censored Tobit, and bootstrapped-truncated regression are employed to model the fund ratings. The results are acceptable, indicating that four or five out of the sixteen sample funds depending on the model employed can be candidates for value investors. Moreover, although there is not much evidence for systematic effects of the beta coefficient on fund rating, the findings of the analyses entail implications for potential investors by using the models as an investment pick and for fund managers by considering the mitigation of risk and bringing higher selectivity to their portfolios.

DEA performance assessment of Greek listed metallurgical firms

Purpose – This paper aims to assess two distinct aspects of performance in terms of technical (sales) efficiency and efficiency in market value generation of a sample of Greek metallurgical firms listed on the Athens Exchange by using data envelopment analysis (DEA). Design/methodology/approach – Both aspects of performance are measured by employing the DEA BCC model, combined with bootstrap and generalized proportional distance function (GPDF). Statistical analysis is performed to investigate whether there is a positive link between the two examined performance dimensions. Findings – Inefficiency is uncovered in both performance dimensions, but there is a lower level of performance in market value generation than in technical efficiency. Correlation analysis results do not point out positive links between performance measures for the sample firms. Research limitations/implications – The derived performance measures allow firm managers to set their own priorities and to seek out improvements along the two...