“…Garcıa-Sanchez (2006), by using DEA with the data of 24 water utilities, cannot find any efficiency differences between publicly and privately owned companies in Spain. Stiel (2017), with a newly constructed and unique dataset from the German Federal Statistical Office, investigates the link between organizational innovation and productivity by focusing on three elements, namely, corporatization, outsourcing, and partial privatization. The data comprised 2,325 German state-owned firms for energy and water supply between 2003 and 2014 (German energy and water firms are multiproduct firms).…”