Publications by Year: 2014

Journal Article
Tsakas, M. & Katharaki, M., 2014. Impact of environmental factors on the efficiency of tax organizations. Serbian Journal of Management, 9, pp.31 – 43. Website Abstract
The study examines the performance of tax organizations in Greece, based on data obtained from a sample of 35 tax offices. Performance evaluation was conducted using DEA with bootstrap methods. In addition, Tobit regression analysis was employed to examine the environmental variables that impact on the efficiency performance of these tax offices. From the analysis, weaknesses, and management issues are derived from the tax offices inefficiency. The general conclusion is that a robust governance structure within the tax office operational framework is needed in order to improve organisational efficiency.
Katharakis, G., Katharaki, M. & Katostaras, T., 2014. An empirical study of comparing DEA and SFA methods to measure hospital units' efficiency. International Journal of Operational Research, 21, pp.341 – 364. Website Abstract
The paper aims to examine the data envelopment analysis (DEA) and stochastic frontier analysis (SFA) results in order to facilitate a common understanding about the adequacy of these methods, defining any differences in healthcare efficiency estimation. A two-stage bootstrap DEA method and the Translog formula of the SFA were performed. Multi-inputs and multi-outputs were used in both of the approaches assuming two scenarios either including environmental variables or not. Thirty-two Greek public hospital units constitute the sample. DEA and SFA were found to yield divergent efficiency estimates due to many factors such as the nature of the environmental variables, the measurement error and other random factors. Environmental variables being hospital status and geographical position were found significantly correlating with inefficiency. The analysis concludes that the choice of the appropriate mathematical form depends on the expertise of the researcher and the purpose of the evaluation. Copyright © 2014 Inderscience Enterprises Ltd.