In this thesis, I apply a comparative deterministic and non-parametric method for calculating production efficiency, called Data Envelopment Analysis (DEA). DEA is based on the seminal article of Farrell (1957) and was introduced by Charnes et al. (1978) to assess the efficiency of decision-making units (DMUs). DEA has been continuously improved and adapted for new areas of application so that its various enhancements have become the most widely used efficiency assessment technique in economics and operations research (Emrouznejad et al., 2018).

The five studies in this thesis contribute to the existing literature by focusing on technical challenges and by emphasising methods and operational aspects of DEA. The first two studies are more technically focused and build the basis for the three empirical papers. The latter are efficiency evaluations of secondary and tertiary education institutions and an encompassing assessment of countries. Although DEA is one of the most widely used efficiency assessment techniques, operational and methodology aspects are often insufficiently emphasised in the majority of efficiency evaluations (Cook et al., 2009b).