“…Diener et al 1985Diener et al , 1999Diener et al , 2003Kahneman and Krueger 2006;Dolan and White 2007), it has been suggested (Dolan and Metcalfe 2012;Hicks et al 2013;O'Donnell et al 2014) that to fully measure and understand individuals' subjective wellbeing, researchers and policy-makers should take into account three components: an "evaluative" or cognitive dimension, reflecting overall life satisfaction; an "eudemonic" dimension, reflecting sense of life purpose; and an "emotional" dimension, including both positive affective states, such as happiness and joy, and negative affective states, such as sadness and worry. The latter distinction has been shown to be important, as positive and negative emotions appear to be independent from each other (Diener and Emmons 1984;Diener et al 1995), and, as such, they are not simply "the opposite ends of a continuum" (Cohen et al 2003, p. 652).…”