The World Health Organisation’s Quality of Life
assessment group defines quality of life as ‘‘individuals’
perception of their position in life in the context of the
culture and the value system in which they live and in
relation to their goals, expectations, standards and concerns’’
[41, p. 1405].What influences quality of life? Two
potential determinates are objective and subjective factors
[22]. Objective factors include income, health, marital
status, gender, and age. Intuitively we may think that
having more of these things means greater quality of life.
However, in the area of happiness research, objective
factors are less powerful than one might expect. Lyubomirsky
et al. [29, 30] propose that objective factors
account for about 8–15% of the difference in happiness.