4.1Operating costs (CG 300)
4.1.1Theoretical basis and variables
A data sample of 194 observations including a training sample of 176 observations and a test sample of 18 observations serves as a basis for the empirical investigation of operating costs (CG 300). Individual observations of the total sample are excluded from the data basis of the current analysis due to the limited availability of data. The underlying cost data of the current analysis are aggregated from several second level cost groups according to the the standard DIN 18960:2008-02. Excluded observations are described in detail in the theoretical basis of the particular second level cost groups in the subsequent Sections. The underlying cost data of operating ...