An Evaluation and Efficiency Analysis of Railways Safety: A Case Study of EU and Turkey

2. Literature Review

The purpose of the researches of the authors in the field of transportation is to provide a measurement of productivity and justify a system of regulation for transportation effectiveness, to analyze the factors for technical change in different modes. Many mathematical models which have been applied are pricing models (Arrigo and Di Foggia 2014), cost function (Loizides and Tsionas 2002);(Urdánoz and Vibes 2013), distance functions(Coelli and Perelman 2000)(Lan and Lin 2006) Malmquist productivity model (P. Cantos, Pastor, and Serrano 1999), nonparametric frontier model, data envelopment analysis(Pedro Cantos, Pastor, and Serrano 2002);(Yu and Lin 2008), regression analysis by quadratic function and requirement function, analysis by operational and technical indicators(de Jorge and Suarez 2003) , but regarding to the newest studies using alternative methodologies, it is not possible to evaluate efficiency precisely, so we can only use these studies to define good or bad operations(Cowie and Riddington 1996) .