The aim of this paper is to examine the impact of socio-economic status (SES) on the Body Mass Index (BMI), a formula based on the ratio of height to weight, linked to health, using a four-year (1991, 1993, 1997 and 2000) panel data set which comes from the Physical Examination in China Health...

Cooperative behavior is common in nature even if selfishness is sometimes better for an individual. Empirical and theoretical studies have shown that the invasion and expansion of cooperators are related to an inhomogeneous connectivity distribution. Here we study the evolution of cooperation on...