Portrait of Professor Subal C. Kumbhakar

Professor Subal Kumbhakar : Associate

Subal is a world-renowned expert in productivity and performance measurement, with particular emphasis on the theory and application of stochastic frontier analysis (SFA). He has been working in the area of efficiency and productivity for the last 35 years, and has developed models to measure performance for a variety of industries such as energy, post office, transport, water, agriculture, manufacturing, public utilities, aquaculture, hospitality, health, banking and school systems. He has published more than 250 papers in refereed international academic journals. He is a Distinguished University Professor at the State University of New York at Binghamton, where he teaches theoretical and applied econometrics and statistics courses at both undergraduate and postgraduate levels. Subal is a highly sought-after keynote speaker at the international productivity and efficiency conferences. He is also the co-author of the highly influential book Stochastic Frontier Analysis, and lead developer of SFA software.

Subal is a co-editor of Empirical Economics and is on the editorial board, or is an associate editor, of the following journals: Journal of Productivity Analysis, Journal of Regulatory Economics, Journal of Agricultural and Applied Economics, Technological Forecasting and Social Change, International Journal of Business and Economics, Applied Econometrics, Ecos de Economía: A Latin American Journal of Applied Economics.

Oxera Associates are highly skilled independent experts who are recognised within a variety of sectors. These individuals have a wealth of knowledge within their fields, and our collaboration with them means that we can offer the best advice, inspiring our clients to make better decisions.

Subal speaks English.

Tel: +44 (0) 1865 253000

Subal's specialisms include:

professional experience

  • Advice on regulatory issues, productivity and efficiency for RIIO-GD2 controls (2017–21)

  • Advice to water companies on regulatory and efficiency issues during PR19 and during the CMA inquiry into the appeal of the PR19 Final Determinations (2016–21)

  • Advice to the Danish Competition and Consumer Authority on integrating quality measures within cost benchmarking (2019–20)

  • Advised South West Water during the CMA inquiry into its merger with Bournemouth Water (2015)

  • Advice to water companies on regulatory and efficiency issues during PR14, including advice to Bristol Water during the CMA inquiry into its appeal of the PR14 Final Determinations (2013–15)

  • Advice on efficiency issues for an electricity DNO for RIIO-ED1 (2011–12)


  • Kumbhakar, S., Wang, H.-J. and Horncastle, A. (2015), A Practitioner’s Guide to Stochastic Frontier Analysis, Cambridge University Press.

  • Ray, S.C., Chambers, R. and Kumbhakar, S. (forthcoming), Handbook of Production Economics (vols 1 and 2), Springer Nature Singapore.

  • Kumbhakar, S., Parmeter, C. and Malikov, E. (forthcoming), Empirical Economics, special issue on productivity and efficiency.

  • Kumbhakar, S. and Horncastle, A. (2010), ‘Improving the Econometric Precision of Regulatory Models’, Journal of Regulatory Economics, 38:2, pp. 144–66.


  • PhD Economics, University of Southern California, Los Angeles

  • Masters of Arts Economics, University of Southern California, Los Angeles

  • Masters of Arts Economics, Calcutta University, Calcutta, India