*Article* **European Citizens' Happiness: Key Factors and the Mediating Effect of Quality of Life, a PLS Approach**

**Nuria Huete-Alcocer 1, Víctor-Raúl López-Ruiz 1, José Luis Alfaro-Navarro 2,\* and Domingo Nevado-Peña <sup>3</sup>**


**Abstract:** Happiness is a very important aspect in the life and well-being of all citizens; as such, it has become a key factor in personal preferences. For these reasons, it is relevant to study what factors principally affect the happiness of the population. However, the difficulties involved in measuring this concept mean that there are no clear criteria as to which aspects should be promoted in order for citizens to achieve greater happiness. This paper uses variance-based structural equation modelling (SEM)—partial least squares path modelling (PLS)—to analyse the direct and indirect effects of European citizens' assessment of different aspects of their city related to safety, environmental quality and urban planning on their happiness. The source of information used in this study is the Flash Eurobarometer 419 prepared by Eurostat in 2015, with a total of 9799 observations. The results show how quality of life, safety, the environment and city planning have a positive and significant influence on European citizens' happiness, especially safety. In addition, quality of life acts as a mediating variable, primarily increasing the influence of urban planning on happiness. The findings of the study point to the relevant policies that governments should undertake to ensure the happiness of their citizens.

**Keywords:** happiness; quality of life; safety; environmental quality; urban planning; European cities; mediating effect; PLS-SEM
