Integer-valued DEA super-efficiency based on directional distance function with an application of evaluating mood and its impact on performance

Chen, Y., Djamasbi, S., Du, J., and Lim, S. (2013), Integer-valued DEA super-efficiency based on directional distance function: evaluating mood and its impact on performance, International Journal of Production Economics, December 2013 (146, 2), pp. 550-556.