Economic Discussion Papers

 

Año 2012

Ana González, Celia Bilbao, Ana Rodríguez, Bienes públicos locales y precios turísticos. Una aplicación del modelo hedónico, Economic Discussion Paper, EDP 01/2012, Departamento de Economía, Universidad de Oviedo.

Humberto Brea, Emili Grifell-Tatjé, Luis Orea, Expectations with Unrealistic Optimism: An Empirical Application, Economic Discussion Paper, EDP 02/2012, Departamento de Economía, Universidad de Oviedo.

José Eduardo Castro, Luis Orea, Efecto de la estructura de mercado de los centros comerciales españoles sobre los precios de los bienes al por menor, Economic Discussion Paper, EDP 03/2012, Departamento de Economía, Universidad de Oviedo.

Luis Orea, Jevgenijs Steinbuks, Estimating Market Power in Homogenous Product Markets Using a Composed Error Model: Application to the California Electricity Market, Economic Discussion Paper, EDP 04/2012, Departamento de Economía, Universidad de Oviedo.

 

Año 2011

William Greene, Luis Orea, Alan Wall, A one-stage random effect counterpart of the fixed-effect vector decomposition model with an application to UK electricity distribution utilities, Economic Discussion Paper, Efficiency Series Paper 01/2011, Departamento de Economía, Universidad de Oviedo.

María Pérez Urdiales, Luis Orea, Stochastic Productivity growth and its determinants in the Spanish provinces: Do withinregions differences matter?, Economic Discussion Paper, Efficiency Series Paper 02/2011, Departamento de Economía, Universidad de Oviedo.

Julio Tascón, Misael Arturo López-Zapico, U.S. Political & Economical Influence over the Late-Francoist Spain through Foreign Direct Investment, Economic Discussion Paper, EDP 01/2011, Departamento de Economía, Universidad de Oviedo.

César Rodríguez, Levi Pérez, Víctor Puente, Plácido Rodríguez, Television Audience for Professional Cycling in Spain, Economic Discussion Paper, EDP 02/2011, Departamento de Economía, Universidad de Oviedo.

Misael Arturo López-Zapico, Julio Tascón, The Perspective of the Reagan Administration on Prospective PSOE Economic Policy, Economic Discussion Paper, EDP 03/2011, Departamento de Economía, Universidad de Oviedo.


 

Año 2010

Juan Francisco Canal Dommnguez, César Rodríguez Gutiérrez, Wage Differences among Doctors by Area of Knowledge. Are Science Areas Better Paid than Humanities Ones? , Economic Discussion Paper, EDP 01/2010, Departamento de Economía, Universidad de Oviedo.

Brad R. Humphreys, Levi Pérez, A microeconometric analysis of participation in sports betting markets, , Economic Discussion Paper, EDP 02/2010, Departamento de Economía, Universidad de Oviedo.

Tooraj Jamasb, Luis Orea, Michael G. Pollitt, Weather Factors and Performance of Network Utilities: A Methodology and Application to Electricity, Economic Discussion Paper, Efficiency Series Paper 01/2010, Departamento de Economía, Universidad de Oviedo. (También como EPRG working paper, University of Cambridge).

J. del Corral, J.A. Pérez and D. Roibás, The impact of land fragmentation on milk production, Economic Discussion Paper, Efficiency Series Paper 02/2010, Departamento de Economía, Universidad de Oviedo.

Tooraj Jamasb, Luis Orea, Michael G. Pollitt, Estimating Marginal Cost of Quality Improvements: The Case of the UK Electricity Distribution Companies, Economic Discussion Paper, Efficiency Series Paper 03/2010, Departamento de Economía, Universidad de Oviedo. (También como EPRG working paper, University of Cambridge).

Jaume García, Levi Pérez y Plácido Rodríguez, Elasticidad precio efectivo de la demanda de juegos lotto, Economic Discussion Paper, EDP 03/2010, Departamento de Economía, Universidad de Oviedo.

Víctor Fernández-Blanco, Luis Orea y Juan Prieto, Estimating demand functions with average prices: does it impose endogeneity?, Economic Discussion Paper, EDP 04/2010, Departamento de Economía, Universidad de Oviedo.

William Greene, Luis Orea, Alan Wall, Stochastic Frontiers using a Fixed-effect Vector Decomposition Approach with an Application to ICT and Regional Productivity in Spain, Economic Discussion Paper, Efficiency Series Paper 04/2010, Departamento de Economía, Universidad de Oviedo.

David Roibás, Jose Baños, The Impact of Infrastructures in Provincial Production: Assessing its Dynamic Impact, Economic Discussion Paper, Efficiency Series Paper 05/2010, Departamento de Economía, Universidad de Oviedo.




Año 2009

Levi Pérez , The state of Empirical Research on the Demand for Lottery. , Economic Discussion Paper, EDP 01/2009, Departamento de Economía, Universidad de Oviedo.

V. Cabrera, D. Solis, Julio del Corral, Studyng the impact of managerial activities on the technical efficiency of Wisconsin Dairy farm, Economic Discussion Paper, Efficiency Series Paper 01/2009, Departamento de Economía, Universidad de Oviedo. Other versions: Determinants of Technical Efficiency among Dairy Farms in Wisconsin, Journal of Dairy Science, forthcoming.

Fernando Lera, Jaume Garcia, Maria José Suárez, Estimation of a Structural Model of the Determinants of the Time Spent on Physical Activity and Sport: Evidence for Spain, Economic Discussion Paper, EDP 02/2009, Departamento de Economía, Universidad de Oviedo.

Julio Tascón, La reducida competitividad de la industria turística en España, Economic Discussion Paper, EDP 03/2009, Departamento de Economía, Universidad de Oviedo.

Luis Orea, Entry efficiency and barriers to entry in the Spanish retail market, Economic Discussion Paper, Efficiency Series Paper 02/2009, Departamento de Economía, Universidad de Oviedo.

Luis Orea, Legal and political barriers to entry in the Spanish retail market: a frontier approach.Economic Discussion Paper, Efficiency Series Paper 03/2009, Departamento de Economía, Universidad de Oviedo.

César Rodríguez Gutiérrez, Utilización de los contratos temporales en España
a lo largo del ciclo económico.
Economic Discussion Paper, EDP 04/2009, Departamento de Economía, Universidad de Oviedo

Juan Francisco Canal Domínguez, Manuel Antonio Muñiz
Pérez,
Doctors' Professional Future: University Activity vs. Working at Firm. The Spanish CaseEconomic Discussion Paper, EDP 05/2009, Departamento de Economía, Universidad de Oviedo

Ana Rodríguez-Álvarez, David Roibás, Alan Wall, Factors determining the response of hospitals to demand uncertainty ,Efficiency Series Paper, 05/2009, Departamento de Economía, Universidad de Oviedo

Ana Rodríguez Álvarez, Beatriz Tovar de la Fe, Reformas regulatorias y eficiencia en el sector portuario español ,Efficiency Series Paper, 05/2009, Departamento de Economía, Universidad de Oviedo

Paloma Corrales, Julio del Corral, Luis Orea, Efecto del capital TIC en la eficiencia tecnica: evidencia para las provincias espanolas ,Efficiency Series Paper, 06/2009, Departamento de Economía, Universidad de Oviedo




Año 2008

Luis Orea , The effect of legal barriers to entry in the Spanish retail market: a local market analysis, Economic Discussion Paper, EDP 01/2008, Departamento de Economía, Universidad de Oviedo. Other versions: Orea, L. (2010): The effect of legal barriers to entry in the Spanish retail market: a local market approach, Hacienda Pzblica Espaqola/Revista de Economma Pzblica, prsximamente.

María A. García-Valiñas, Roberto Fernández-Llera y Benno Torgler, More income equality or not? Individuals' preferences for redistribution, Economic Discussion Paper, EDP 02/2008, Departamento de Economía, Universidad de Oviedo.

Manuel Muñiz, Maria. A. Garcia-Valiqas, Productive evaluation of non-cognitive educational outputs: An international comparison, Economic Discussion Paper, EDP 03/2008, Departamento de Economía, Universidad de Oviedo.

César Rodríguez-Gutiérrez y Juan Francisco Canal-Domínguez, The determinants of workers' effort: an analysis of Spanish public and private sectors, Economic Discussion Paper, EDP 04/2008, Departamento de Economía, Universidad de Oviedo.

César Rodríguez-Gutiérrez y Juan Prieto Rodrmguez, Effect of union affiliation on workers' job satisfaction: The Spanish case, Economic Discussion Paper, EDP 05/2008, Departamento de Economía, Universidad de Oviedo.

Andrés J. Picazo-Tadeo, Francisco J. Sáez-Fernández y Francisco González-Gómez, Assesing Performance in the Management of the Urban Water Cycle, Economic Discussion Paper, Efficiency Series Paper 01/2008, Departamento de Economía, Universidad de Oviedo.

Sergio Perelman y Daniel Santín, Imposing Weak Monotonicity on Parametric Distance Function Estimations, Economic Discussion Paper, Efficiency Series Paper 02/2008, Departamento de Economía, Universidad de Oviedo.

Mircea Epure, Kristiaan Kerstens y Diego Prior, Benchmarking and Total Factor Productivity: A Luenberger Decomposition within the Banking Sector, Economic Discussion Paper, Efficiency Series Paper 03/2008, Departamento de Economía, Universidad de Oviedo.

Luis Orea, Ana Rodríguez-Álvarez y Subal Kumbhakar, Explaining Occupancy Rates in the European Railways: a Reduced-Form Approach, Economic Discussion Paper, Efficiency Series Paper 04/2008, Departamento de Economía, Universidad de Oviedo.

 

Año 2007

Julio del Corral, Measuring competitive balance and match specific uncertainty in professional tennis. Are there differences among gender and court surfaces?, Economic Discussion Paper, EDP 01/2007, Departamento de Economía, Universidad de Oviedo.

Julio del Corral, Juan Prieto-Rodríguez y Rob Simmons, The effect of incentives on sabotage: The case of Spanish football, Economic Discussion Paper, EDP 02/2007, Departamento de Economía, Universidad de Oviedo.

Carlos Barros, Julio del Corral y Pedro Garcia-del-Barrio, Identification of Segments of Soccer Clubs in the Spanish League First Division with a Latent Class Model, Economic Discussion Paper, Efficiency Series Paper 01/2007, Departamento de Economía, Universidad de Oviedo.

Luis Orea, Estimating Firm-Specific Market Power: A Composed Error Term Approach, Economic Discussion Paper, Efficiency Series Paper 02/2007, Departamento de Economía, Universidad de Oviedo.

Ana Lozano-Vivas y Jesús Pastor, Do Performance and Environmental Conditions Behave as Barriers for Cross-Country Banking Activity in Europe?, Economic Discussion Paper, Efficiency Series Paper 03/2007, Departamento de Economía, Universidad de Oviedo.

Antonio Álvarez, Julio del Corral, Daniel Solís y José Antonio Pérez, Does Intensification Help to Improve the Economic Efficiency of Dairy Farms?, Economic Discussion Paper, Efficiency Series Paper 04/2007, Departamento de Economía, Universidad de Oviedo.

Andrés Maroto-Sánchez y Juan Ramón Cuadrado-Roura, Productivity and Tertiarization in Industrialized Countries. A Comparative Analysis, Economic Discussion Paper, Efficiency Series Paper 05/2007, Departamento de Economía, Universidad de Oviedo.

Knox Lovell, Ana Rodríguez-Álvarez y Alan Wall, The effects of Stochastich Demand and Expense Preference Behaviour on Public Hospital Cost and Excess Capacity, Economic Discussion Paper, Efficiency Series Paper 06/2007, Departamento de Economía, Universidad de Oviedo.

 

Año 2006

Consuelo Abellán, Florentino Felgueroso y María José Pérez-Villadóniga, Do unions reduce the gender wage gap? An extension of the traditional models of discrimination, Economic Discussion Paper, EDP 01/2006, Departamento de Economía, Universidad de Oviedo.

Daniel Solís, Boris Bravo-Ureta y Ricardo E. Quiroga, Soil Conservation and Technical Efficiency Among Hillside Farmers in Central America: A Switching Regression Model, Economic Discussion Paper, Efficiency Series Paper 01/2006, Departamento de Economía, Universidad de Oviedo.

Antonio Álvarez y David Roibás, An Economic Model to Evaluate the Contribution of Genetics to Milk Production, Economic Discussion Paper (Efficiency Series Papers) 02/2006, Departamento de Economía, Universidad de Oviedo.

Antonio Álvarez y Julio del Corral, Separating Catch-up and Technical Change in Stochastic Frontier Models. A Monte Carlo Approach, Economic Discussion Paper, Efficiency Series Paper 03/2006, Departamento de Economía, Universidad de Oviedo.

Eduardo González y Vicente García, Using Value Efficiency Analysis (VEA) to Measure Productivity Efficiency in Primary Health Care, Economic Discussion Paper, Efficiency Series Paper 04/2006, Departamento de Economía, Universidad de Oviedo.

Bernd Frick y Robert Simmons, Impact of Managerial Quality on Organizational Performance. Evidence from German Soccer, Economic Discussion Paper, Efficiency Series Paper 05/2006, Departamento de Economía, Universidad de Oviedo.

Antonio Álvarez y Julio del Corral, Modeling Regional Heterogeneity with Panel Data: Application to Spanish Provinces, Economic Discussion Paper, Efficiency Series Paper 06/2006, Departamento de Economía, Universidad de Oviedo.

 

Año 2005

Boris Bravo-Ureta, Daniel Solís, Victor Moreira, José Maripani, Abdourahmane Thiam, y Teodoro Rivas,Technical

 Efficiency in Farming: A Meta-regression analysis,

Economic Discussion Paper, Efficiency Series Paper 01/2005, Departamento de Economía, Universidad de Oviedo.

Antonio Álvarez , Decomposing Regional Productivity Growth using an Aggregate Production Frontier, Economic Discussion Paper, Efficiency Series Paper 02/2005, Departamento de Economía, Universidad de Oviedo.

Antonio Álvarez, Christine Amsler, Luis Orea y Peter Schmidt , Interpreting and Testing the Scaling Property in Models where Inefficiency Depends on Firm Characteristics, Economic Discussion Paper, Efficiency Series Paper 03/2005, Departamento de Economía, Universidad de Oviedo.

Jorge Rodriguez-Vález, Antonio Álvarez, Carlos Arias y Esteban Fernández, Estimating the Productivity of Public Infrastructure using Maximum Entropy Econometrics, Economic Discussion Paper, Efficiency Series Paper 04/2005, Departamento de Economía, Universidad de Oviedo.

Luis Orea y Alan Wall, Risk-adjusted Productivity Measurement with Application to Spanish Dairy Farms, Economic Discussion Paper, Efficiency Series Paper 05/2005, Departamento de Economía, Universidad de Oviedo.

Carlos Arias y Xosé Antón Rodríguez, The Effects of Resource Depletion on Coal Mining Productivity, Economic Discussion Paper, Efficiency Series Paper 06/2005, Departamento de Economía, Universidad de Oviedo.

Antonio Álvarez, Carlos Arias y William Greene, Accounting for Unobservables in Production Models: Management and Inefficiency, Economic Discussion Paper, Efficiency Series Paper 07/2005, Departamento de Economía, Universidad de Oviedo.

 

Año 2004

Antonio Álvarez, Carlos Arias y Luis Orea, Explaining Differences in Milk Quota Values: The Role of Economic Efficiency, Economic Discussion Paper, Efficiency Series Paper 01/2004, Departamento de Economía, Universidad de Oviedo.

Joaquín Millán, Scale and the Efficiency Production Function, Economic Discussion Paper, Efficiency Series Paper 02/2004, Departamento de Economía, Universidad de Oviedo.

Daniel Santín, On the Approximation of Production Functions: A Comparison of Artificial Neural Networks Frontiers and Efficiency Techniques, Economic Discussion Paper, Efficiency Series Paper 03/2004, Departamento de Economía, Universidad de Oviedo.

Ana Rodríguez, Beatriz Tovar de la Fe y Lourdes Trujillo, Technical and Allocative Efficiency in Spanish Port Cargo Handling Firms, Economic Discussion Paper, Efficiency Series Paper 04/2004, Departamento de Economía, Universidad de Oviedo.

Antonio Álvarez y Luis Orea, Differences in Productivity Between Efficient and Inefficient Firms, Economic Discussion Paper, Efficiency Series Paper 05/2004, Departamento de Economía, Universidad de Oviedo.

David Roibás y Carlos Arias, Endogeneity Problems in the Estimation of Multi-Output Technologies, Economic Discussion Paper, Efficiency Series Paper 06/2004, Departamento de Economía, Universidad de Oviedo.

Julio del Corral y Antonio Álvarez, The Estimation of Different Technologies using a Latent Class Model, Economic Discussion Paper, Efficiency Series Paper 07/2004, Departamento de Economía, Universidad de Oviedo.

Antonio Álvarez, Carlos Arias y Luis Orea, The Measurement of Spatial Productivity Spillovers from Public Capital, Economic Discussion Paper, Efficiency Series Paper 08/2004, Departamento de Economía, Universidad de Oviedo.

 

Año 2003

Rafael A. Cuesta y José L. Zofío, Graph Efficiency and Parametric Distance Function with an Application to Spanish Savings Banks, Economic Discussion Paper, Efficiency Series Paper 01/2003, Departamento de Economía, Universidad de Oviedo.

Antonio Álvarez, Carlos Arias y Subal Kumbhakar, Empirical Consequences of Direction Choice in Technical Efficiency Analysis,. Economic Discussion Paper, Efficiency Series Paper 02/2003, Departamento de Economía, Universidad de Oviedo.

Antonio Álvarez, Leví Pérez y Peter Schmidt, The Relative Importance of Luck and Technical Efficiency in a Fishery, Economic Discussion Paper, Efficiency Series Paper 03/2003, Departamento de Economía, Universidad de Oviedo.

Ana Rodríguez, Víctor Fernández y Knox Lovell, Allocative Inefficiency and its Cost: The Case of the Spanish Public Hospitals, Economic Discussion Paper, Efficiency Series Paper 04/2003, Departamento de Economía, Universidad de Oviedo.

Jean-Paul Chavas, Ragan Petrie, y Michael Roth, Farm Household Production Efficiency: Evidence from The Gambia, Economic Discussion Paper, Efficiency Series Paper 05/2003, Departamento de Economía, Universidad de Oviedo.

Subal Kumbhakar y Efthymios Tsionas, Recent Developments in Stochastic Frontier Modeling, Economic Discussion Paper, Efficiency Series Paper 06/2003, Departamento de Economía, Universidad de Oviedo.

Robert J. Gordon, Europe Chasing the American Frontier, Economic Discussion Paper, Efficiency Series Paper 07/2003, Departamento de Economía, Universidad de Oviedo.

Subal Kumbhakar, Luis Orea, Ana Rodríguez y Efthymios Tsionas, Estimating a Mixture of Efficiency Indices, Economic Discussion Paper, Efficiency Series Paper 08/2003, Departamento de Economía, Universidad de Oviedo.

Antonio Álvarez, Econometric Estimation of Fishing Production Functions when Stock is Unknown: A Monte Carlo Analysis, Economic Discussion Paper, Efficiency Series Paper 09/2003, Departamento de Economía, Universidad de Oviedo.

Joaquín Millán, On Graph Efficiency Measurement, Economic Discussion Paper, Efficiency Series Paper 10/2003, Departamento de Economía, Universidad de Oviedo.

 

Año 2002

Tim Coelli, Emili Grifell-Tatje y Sergio Perelman, Capacity Utilization and Profitability: A Decomposition of Short Run Profit Efficiency, Economic Discussion Paper, Efficiency Series Paper 01/2002, Departamento de Economía, Universidad de Oviedo.

Ana Rodríguez, Ignacio del Rosal y José Baños, Rent-Seeking Measurement in Coal Mining by Means of Labour Unrest: An Application of the Distance Function, Economic Discussion Paper, Efficiency Series Paper 02/2002, Departamento de Economía, Universidad de Oviedo.

Walter Briec, Kristiaan Kerstens y Philippe Vyen Eeckaut, Non-Convex Technologies and Cost Functions: Definitions, Duality and Nonparametric Tests of Convexity, Economic Discussion Paper, Efficiency Series Paper 03/2002, Departamento de Economía, Universidad de Oviedo.

Luis Orea, David Roibás y Alan Wall, Choosing the Technical Efficiency Orientation to Analyze Firms’ Technology: A Model Selection Test Approach, Economic Discussion Paper, Efficiency Series Paper 04/2002, Departamento de Economía, Universidad de Oviedo.

Chirok Han, Luis Orea y Peter Schmidt, Estimation of a Panel Data Model with Parametric Temporal Variation in Individual Effects, Economic Discussion Paper, Efficiency Series Paper 05/2002, Departamento de Economía, Universidad de Oviedo.

Lilyan Fulginiti y Richard Perrin, Productivity and Welfare, Economic Discussion Paper, Efficiency Series Paper 06/2002, Departamento de Economía, Universidad de Oviedo.

Spiro Stefanou, Onelack Choi, y Jeffrey Stokes, The Dynamics of Efficiency Improving Input Allocation and Reorganization Costs, Economic Discussion Paper, Efficiency Series Paper 07/2002, Departamento de Economía, Universidad de Oviedo.

José E. Boscá, Javier Escribá y Mª.José Murgui, TFP Growth in Spanish Regions: Effects of Quasi-Fixed and External Factors and Varying Capacity Utilization, Economic Discussion Paper, Efficiency Series Paper 08/2002, Departamento de Economía, Universidad de Oviedo.

Natalia Aldaz y Joaquín Millán, An Inter-Country Comparison of Agricultural Productivity with Intertemporal DEA, Economic Discussion Paper, Efficiency Series Paper 09/2002, Departamento de Economía, Universidad de Oviedo.

Antonio Estache, Marianela González y Lourdes Trujillo, What does “Privatization” do for Efficiency? Evidence from Argentina and Brazil’s Railways, Economic Discussion Paper, Efficiency Series Paper 10/2002, Departamento de Economía, Universidad de Oviedo.

Luis Orea y Subal Kumbhakar, Measuring Efficiency using a Stochastic Frontier Latent Class Model, Economic Discussion Paper, Efficiency Series Paper 11/2002, Departamento de Economía, Universidad de Oviedo.

Luis Orea y Alan Wall, Decomposing Productivity Growth under Production Risk, Economic Discussion Paper, Efficiency Series Paper 12/2002, Departamento de Economía, Universidad de Oviedo.

 

Año 2001

Knox Lovell, Future Research Opportunities in Efficiency and Productivity Analysis, Economic Discussion Paper, Efficiency Series Paper 01/2001, Departamento de Economía, Universidad de Oviedo.

Antonio Álvarez, Some Issues on the Estimation of Technical Efficiency in Fisheries, Economic Discussion Paper, Efficiency Series Paper 02/2001, Departamento de Economía, Universidad de Oviedo.

Eduardo González y Ana Cárcaba, A Resource-Based Interpretation of Technical Efficiency Indexes, Economic Discussion Paper, Efficiency Series Paper 03/2001, Departamento de Economía, Universidad de Oviedo.

Antonio Álvarez y Luis Orea, Different Methods of Modeling Multi-Species Fisheries Using a Primal Approach, Economic Discussion Paper, Efficiency Series Paper 04/2001, Departamento de Economía, Universidad de Oviedo.

Antonio Álvarez y Carlos Arias, The Relationship Between Technical Efficiency and Farm Size, Economic Discussion Paper, Efficiency Series Paper 05/2001, Departamento de Economía, Universidad de Oviedo.

William Greene, New Developments in the Estimation of Stochastic Frontier Models with Panel Data, Economic Discussion Paper, Efficiency Series Paper 06/2001, Departamento de Economía, Universidad de Oviedo.

Daniel Henderson y Robert Russell, Human Capital and Macroeconomic Convergence: A Production-Frontier Approach, Economic Discussion Paper, Efficiency Series Paper 07/2001, Departamento de Economía, Universidad de Oviedo.

George Battese, D.S. Prasada Rao y Dedi Walujadi, Technical Efficiency and Productivity Potential of Firms Using a Stochastic Metaproduction Frontier, Economic Discussion Paper, Efficiency Series Paper 08/2001, Departamento de Economía, Universidad de Oviedo.

Daniel Santín, Francisco Delgado y Aurelia Valiño, Measuring Technical Efficiency with Neural Networks: a Review, Economic Discussion Paper, Efficiency Series Paper 09/2001, Departamento de Economía, Universidad de Oviedo.

Francisco Pedraja, Javier Salinas y Peter Smith, Evaluating the Introduction of a Quasi-Market in Community Care: Assessment of a Malmquist Index Approach, Economic Discussion Paper, Efficiency Series Paper 10/2001, Departamento de Economía, Universidad de Oviedo.

Ana Isabel Fernández, Fernyo Gascón y Eduardo González, Economic Efficiency and Value Maximization in Banking Firms, Economic Discussion Paper, Efficiency Series Paper 11/2001, Departamento de Economía, Universidad de Oviedo.