Photo: flickr/tax creditsThis study comes straight out of our new favorite journal, the aptly named International Journal of Manpower. Here, the author set out to determine whether there's a relationship between how much money a person earns and how much sex they have. From a survey of 7,500 people, he found that workers who have sex 2-3 times per week earn on average 4.5 percent more than workers who have sex less often. The direction of causality is still unclear (do people have more sex because they make more money, vice versa, or perhaps there are cases of each?). All we know for sure is that we are submitting our next paper to the International Journal of Manpower. The effect of sexual activity on wages "Purpose – The purpose of this paper is to estimate whether sexual activity is associated with wages, and also to estimate potential interactions between individuals’ characteristics, wages and sexual activity. Design/methodology/approach – The central hypothesis behind this research is that sexual activity, alike health indicators and mental well-being, may be thought of as part of an individual’s set of productive traits that affect wages. Using two-stage estimations the author examines the relationship between adult sexual activity and wages. Findings – The author estimates that there is a monotonic relationship between the frequency of sexual activity and wage returns, whilst the returns to sexual activity are higher for those between 26 and 50 years of age. In addition, heterosexuals’ sexual activity does not seem to provide higher or lower wage returns than that of homosexuals, but wages are higher for those health-impaired employees who are sexually active. Over-identification tests, robustness checks, falsification tests, as well as, decomposition analysis and sample selection modelling enhance study’s strength. Social implications – Contemporary social analysis suggests that health, cognitive and non-cognitive skills and personality are important factors that affect wage level. Sexual activity may also be of interest to social scientists, since sexual activity is considered to be a barometer for health, quality of life, well-being and happiness. Originality/value – The paper adds to the literature on the importance of unobserved characteristics in determining labour market outcomes." Related content: Money can’t buy you love, but it can reduce your pain.Which makes you happier: anticipating an experience or a purchase?ex burns 3.6 calories a minute.