*4.1.2. Tourism activity, economic growth and other productive factors*

The need to consider other productive factors when analysing the relationship between tourism activity and economic growth has been demonstrated by [12]. Despite this, there has been little inclusion of additional factors in the study of the contribution of tourism activity to growth. Thus, of the 87 studies reviewed in [61], only 16 include other determining factors of economic growth, with only 5 studies incorporating these variables when the analysis is made using a time series [12,63,68,94,95]. The economic factors that are included refer to private or public (infrastructures) capital stock, human capital and technological capital. There are only a few studies that also include other factors, such as the indicators of freedom [96] or life expectancy [97].

In spite of the small number of studies that introduce these factors into the analysis, in [79] the importance of their inclusion is shown for suitably measuring the contribution of tourism to growth. Thus, these authors indicate that the inclusion of additional variables tends to diminish the value of the elasticity of productivity with respect to tourism activity.
