CIT2016 – XII Congreso de Ingeniería del Transporte València, Universitat Politècnica de València, 2016. DOI: http://dx.doi.org/10.4995/CIT2016.2016.4072 . This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC- ND 4.0). MODELLING PERCEIVED QUALITY FOR URBAN TRANSPORT SYSTEMS USING WEIGHTED VARIABLES AND RANDOM PARAMETERS Eneko Echaniz Beneitez Researcher, University of Cantabria, Spain Luigi dell’Olio Associate Professor, University of Cantabria, Spain Ángel Ibeas Portilla Associate Professor, University of Cantabria, Spain ABSTRACT In this article, an Ordered Logit model is proposed considering systematic and random variations in tastes. The methodology followed for the creation of this model consisted, in first place, in obtaining data using a revelled preferences survey. In the survey, each user had to evaluate, following a qualitative scale, each one of the attributes of the analysed transport system. The variables evaluated in the survey had been grouped into six groups, and for each group, users had to order the attributes belonging to the group, using a ranking based method, from the most important to de least important, and, in the same way, with the groups itself. Once the database is formed, a generic model have been created, establishing this model as a comparative base for the rest. Next, two more models have been estimated one considering systematic users variations and the other one combining the systematic variations with weighted variables. Additionally, three new models have been calculated as an evolution of the previous ones using random variables as representation of systematic and random variations in user’s tastes. The results shows that as model’s complexity increase, an improvement in model fit is achieved. Keywords Perceived Quality, Ordered Probit, Urban Public Transport, Revealed Preference Survey, Focus Group. 1. INTRODUCTION Understanding the level of satisfaction of transport public users is essential in order to developed public transport systems based marketing plans in urban areas. A global definition of the quality has not been achieved yet. Reeves and Bednar (1994) concluded that a global definition of “quality” does not exist, and, depending the circumstances or the market where the product or service can be located, different definitions