Title: Addressing the endogeneity issue in DEA applications
Speaker: Gabriela Sicilia
Date: 27/07/2016 12:00 h
Location: Sala de Seminarios, Edificio Torretamarit
Abstract:
The presence of the endogeneity is frequently observed in several economic production processes, however, it has received little attention in the frontier literature and it is overlooked when practitioners apply data envelopment analysis (DEA). Recently, Cordero, Santín and Sicilia (2015) concluded that when one input in the production process is highly and positively correlated with the true efficiency level, endogeneity arises and DEA estimates are flawed. In addition, they find that this decline in DEA performance is further driven by the misidentification of the most inefficient DMUs with low levels of the endogenous input. These findings take on greater significance since high positive endogenous scenarios are similar to those that are likely to be found in many production processes. In this context, the estimation of the technical efficiency using DEA models without taking into account the presence of endogeneity leads to inaccurate efficiency estimates where many of the most inefficient DMUs are identified as benchmarks, which will lead to inappropriate performance-based recommendations. Building upon this evidence, in this research we address two key issues: how can we detect the presence of an endogenous input? And, how can we deal with this problem in DEA empirical applications to overcome this problem and improve estimations? First, we provide a simple heuristic procedure which allows practitioners to identify the presence of an endogenous input in an empirical research. Second, we propose the use of an instrumental input DEA (II-DEA) as a potential solution to deal with the endogeneity problem in order to improve DEA estimations. Monte Carlo results confirm that II-DEA approach outperforms standard DEA when an input has a high a positive correlation with the technical efficiency. Finally, we perform an empirical application to illustrate our theoretical findings.
Brief Bio:
Ph.D. in Economics at Complutense University of Madrid (2015). Her main lines of research are the measurement of efficiency and productivity and causal inference applied to the field of education, combining both methodological and applied elements. Her work has led to several publications in scientific international journals such as the European Journal of Operational Research, Scientometrics, Pacific Economic Review, Latin American Economic Review and The Social Science Journal and have been discusssed in more than 20 national and international conferences and workshops. She has also participated in several competitive research projects and is a regular contributor to the European Foundation Society and Education.
Title: Managerial and Program Inefficiency for European Meat Manufacturing Firms: A Dynamic Multidirectional Inefficiency Analysis Approach
Speaker: Magdalena Kapelko
Date: 13/07/2016 12:00h
Location: Sala de Seminarios, Edificio Torretamarit
Abstract:
This paper proposes a dynamic multidirectional inefficiency analysis approach within the context of Data Envelopment Analysis to measuring input- and investment-specific managerial and program inefficiency for groups of firms characterized by different technologies. Dynamic managerial inefficiency refers to the distance to the firms’ group-specific frontier of best practices, and dynamic program inefficiency measures the difference between the group-specific frontier and the pooled frontier. The empirical application focuses on panel data of large meat processing firms in Eastern, Western and Southern Europe over the period 2015-2012. The results show that Eastern European firms have the highest dynamic managerial inefficiency for all inputs, but have the smallest values for dynamic program inefficiency. Western European firms perform worst in terms of program inefficiency for all inputs, while Southern European firms score highest for dynamic managerial inefficiency. The results also reveal that regardless the dynamic inefficiency dimension considered, investments is the most inefficient input, followed by labor, and materials.
Brief Bio:
Magdalena Kapelko is an Assistant Professor at Wroclaw University of Economics in Poland. She was a Visiting Assistant Professor at Universidad Carlos III de Madrid and Visiting Researcher at Wageningen University in the Netherlands, Universidad Miguel Hernandez in Spain, University of Florida in the USA, and Linnaeus University in Sweden. She received a PhD and MPhil from Universitat Autònoma de Barcelona in Spain, and a MSc from Wroclaw University of Technology in Poland. Her research specialization is in the area of efficiency and productivity analysis, applied to different business sectors.
Title: Generalized Transport Costs, Accessibility Gains, and Road Transport Infrastructure in Spain
Speaker: Jose Luis Zofío
Date: 06/07/2016 12:00h
Location: Sala de Seminarios, Edificio Torretamarit
Abstract:
Accessibility, the relative access to markets, is a strategic concept in all economic models with a spatial dimension and its prominence has been acknowledged in many economic research fields and policy debates. This paper is based on the assumption that infrastructure, through generalized transport costs between locations, drives economic accessibility and, therefore, we can assimilate a production function approach where the road network constitutes a set of inputs yielding access to markets as output.
Methodologically, we originally measure the infrastructure inputs accounting for the real used network and calculate a series of new final and intermediate demand gravity-based and locational indicators, which capture a wide range of economic transactions and represent different concepts of economic accessibility outputs. The value added of this paper is translating a non-parametric frontier approach (DEA) to a dynamic scope (Malmquist indices) by connecting the regional accessibility to the productivity of the road infrastructure inputs associated with each region. Results during 1995–2005 show a low relative accessibility of the Spanish NUTS-3 regions, although improvements have been greater over the last five years. Finally, we observe a U-inverted relationship between the accessibility gains during these years and the geographical localization.
Brief Bio:
José L. Zofío is Professor of Economics since 2014. He received his PhD in Economics from Universidad Autónoma de Madrid in 2000. His research fields of interest are Productivity and Efficiency (Stochastic Frontier Analysis and Data Envelopment Analysis), Spatial Economics (New Trade Theory and New Economic Geography), Industrial Organization (Competition Policy and Regulation), Environmental Economics and Copyright Industries. He has published many articles in international journals, led relevant research projects, and supervised several dissertations related to the above fields. A list of his most relevant publications can be found in IDEAS (https://ideas.repec.org/e/pzo21.html) and Google Scholar.
Title: Size, Subsidies and Technical Efficiency in Renewable Energy Production: an Empirical Study of Austrian Biogas Plants.
Speaker: Bernhard Mahlberg
Date: 05/05/2016 12:00 h
Location: Sala de Seminarios, Edificio Torretamarit
Abstract:
The aim of this paper is to measure the efficiency of biogas plants in Austria and identify causes of inefficiency. Data Envelopment Analysis (DEA) is applied on a representative sample of 86 biogas plants covering about one third of the installed electric capacity of Austrian biogas plants. By comparing each plant with all other plants, DEA provides a relative performance measure and identifies the plants operating efficiently. In a second-stage regression analysis the effects of subsidies and other environmental variables on efficiency are investigated. The main results are: i) 34% of biogas plants in our sample are technically efficient, 40% are scale efficient and 50 % are purely technically efficient; ii) small biogas plants (≤100 kW) are scale inefficient exhibiting increasing returns to scale; iii) plants with an enclosed digestate storeage unit are more efficient; iv) the relationship between production subsidies and pure technical efficiency is significantly negative; v) the correlation between investment subsidies and pure technical efficiency is negative but insignificant. The results are consistent with the hypothesis that production subsidies provide a disincentive to managerial effort of plant operators.
Brief Bio:
Bernhard Mahlberg is Senior Researcher at the Institute for Industrial Research (IWI) and Lecturer at the Vienna University of Economics and Business (WU Wien). Prior to joining the IWI he worked at the Vienna University of Economics and Business (first as Research Assistant at the Department of Economic Theory and Policy and then as Assistant Professor at the European Institute) and the Austrian Institute of Economic Research. His thesis quantified the effects of the single European market on Austrian and German insurance companies. The main research interests of Bernhard Mahlberg are efficiency and productivity analyzes with data envelopment analysis, Energy and Environmental Economics and Applied input-output models.
Title: A unified view of metaheuristics for multi-objective optimization
Speaker: El-Ghazali Talbi
Date: 27/04/2016 11:00 h
Location: Sala de Seminarios, Edificio Torretamarit
Abstract:
The aim of this talk is to present a unified view of metaheuristic approaches for multi-objective optimization. Following three main issues dealing with fitness assignment, diversity preservation and elitism, a robust and flexible model is introduced. This model is validated by demonstrating how state-of-the-art methods can conveniently fit into it. Then, a modular implementation is proposed and is successfully integrated in a general purpose software framework dedicated to the reusable design of multi-objective metaheuristic optimization techniques such as evolutionary algorithms.
Brief Bio:
El-Ghazali Talbi received the Master and Ph.D. degrees in Computer Science from the Institut National Polytechnique de Grenoble in France. He is a full Professor at the University of Lille and the head of DOLPHIN research group from both the Lille’s Computer Science laboratory (LIFL, Universite Lille 1, CNRS) and INRIA Lille Nord Europe. His current research interests are in the field of multi-objective optimization, parallel algorithms, metaheuristics, combinatorial optimization, cluster and cloud computing, hybrid and cooperative optimization, and applications to logistics/transportation, bioinformatics and networks. Professor Talbi has to his credit more than 150 international publications including journal papers, book chapters and conferences proceedings.
Title: Economic Geography and Infrastructures: Implications for Agglomeration and Regional Cohesion
Speaker: Javier Barbero
Date: 14/04/2016 11:00
Location: Sala de Seminarios, Edificio Torretamarit
Abstract:
Economic geography is the study of where economic activity takes place and what are the underlying forces explaining it. To the traditional questions that economics aims to answer – what to produce, how to produce, and for whom to produce – economic geography adds a new important one: where to produce. In this talk research results of a doctoral thesis on how accessibility and market size affects the location of economic activity are presented. Resorting on network theory we are able to model the transportation infrastructure of a country and, depending on the network topology, determine how economic activity is unevenly distributed across space. This allows us to draw policy implications on ow infrastructure policy should be targeted to increase cohesion between regions.
Brief Bio:
Javier Barbero is Ph.D. in Economics and he holds MSc in International Economic by the Universidad Autónoma de Madrid. He received a scholarship from the Spanish Ministry of Education in 2012. He has made research stays at the Université du Québec à Montréal and at The London School of Economics and Political Science. His research fields are economic theory, spatial economics, location theory, and the introduction of network theory and computational methods in economic analysis, among others. He participates as a researcher in projects financed by ministries and public and private administrations.
Title: A Data Envelopment Analysis Toolbox for MATLAB
Speaker: Javier Barbero
Date: 08/04/2016 12:00
Location: Sala de Seminarios, Edificio Torretamarit
Abstract:
Data Envelopment Analysis Toolbox is a new package for MATLAB that includes functions to calculate the main DEA models. The package includes code for the standard additive and radial input and output measures, allowing for constant and variable returns to scale, as well as recent developments related to the directional distance function, and including both desirable and undesirable outputs when measuring efficiency and productivity; i.e., Malmquist and Malmquist-Luenberger indices. Bootstrapping to perform statistical analysis is also included. In this talk we are going to describe the methodology and implementation of the functions and show numerical results with well-known examples to illustrate their use. Data Envelopment Analysis Toolbox is available as free software, under the GNU General Public License version 3, and can be downloaded from http://www.deatoolbox.com, with all the supplementary material (data, examples and source code) to replicate all results to be presented during the talk. Users will benefit from the collaboration and review of the community, and can check the code to learn how DEA optimizing programs are translated into suitable code.
Brief Bio:
Javier Barbero is Ph.D. in Economics and he holds MSc in International Economic by the Universidad Autónoma de Madrid. He received a scholarship from the Spanish Ministry of Education in 2012. He has made research stays at the Université du Québec à Montréal and at The London School of Economics and Political Science. His research fields are economic theory, spatial economics, location theory, and the introduction of network theory and computational methods in economic analysis, among others. He participates as a researcher in projects financed by ministries and public and private administrations.
Title:
Exploring cross-country differences in the efficiency of schools
Speaker:
JOSE M. CORDERO
Date:
21/10/2015 17:00h
Location:
Sala de Seminarios, Edificio Torretamarit
Abstract:
The participation of the majority of nations on common international large-scale assessments like PISA, TIMSS or PIRLS has provided researchers with extensive cross-national databases that can be used to assess the performance of educational systems from a comparative perspective. Most cross-national studies usually apply econometric techniques to detect significant relationships between output and input variables, thus they do not consider the potential existence of potential inefficiencies in the performance of schools. In this seminar, I will present the results of two different empirical papers in which I have applied some recently developed frontier nonparametric methods to explore the main contextual factors that explain the existing divergences in school performance across countries. In particular, the robust order-m are used to estimate efficiency measures of school performance, then the metafrontierapproach is adapted to this framework to decompose the estimated inefficiency between two different levels (school and country) and, finally, the conditional nonparametric approach are applied to obtain efficiency scores considering the effect of those external factors and explore their potential influence at different levels (school and country).
Brief Bio:
José Manuel Cordero Ferrera is an Associate Professor in the Department of Economics of the University of Extremadura. He holds a degree and Ph.D. in Economics from the same university. His scientific research has been mainly focused in the following fields: efficiency measurement in the public sector, economics of education and fiscal federalism. His research experience in the aforementioned fields has been reflected in multiple scientific articles published in referred journals as well as in several books and book chapters. Those research activities have been funded by various research projects in open calls at national and regional level as well as several grants from the Spanish Institute for Fiscal Studies. Likewise, he has attended numerous conferences and congresses in Spain and worldwide such as the European and North American Efficiency and Productivity workshops.
Sorry, this entry is only available in European Spanish.
| 12 June, 2015 | a | 13 June, 2015 |
“The Santander Chair 2015 International Workshop of Efficiency and Productivity” will be held on June 12 & 13, 2015, in the Spa Porta Maris Hotel.
The Chair plans to edit a book with Springer related to the Workshop presentations.
