Aggregation of Malmquist productivity indexes

In this paper we extend the work of [Färe and Zelenyuk , 2003. On aggregate farrell efficiency scores. European Journal of Operational Research 146(3) 615–620] to find a theoretically justified method of aggregating Malmquist Productivity Indexes over individual decision making units (firms, countries, etc.) into a group Malmquist Productivity Index. We also consider the aggregation of decomposed parts of the Malmquist Productivity Index to obtain a decomposition of the Malmquist Productivity Index for a particular group.