Learn More
OBJECTIVES To evaluate whether happiness can spread from person to person and whether niches of happiness form within social networks. DESIGN Longitudinal social network analysis. SETTING Framingham Heart Study social network. PARTICIPANTS 4739 individuals followed from 1983 to 2003. MAIN OUTCOME MEASURES Happiness measured with validated four item(More)
BACKGROUND The prevalence of obesity has increased substantially over the past 30 years. We performed a quantitative analysis of the nature and extent of the person-to-person spread of obesity as a possible factor contributing to the obesity epidemic. METHODS We evaluated a densely interconnected social network of 12,067 people assessed repeatedly from(More)
BACKGROUND The prevalence of smoking has decreased substantially in the United States over the past 30 years. We examined the extent of the person-to-person spread of smoking behavior and the extent to which groups of widely connected people quit together. METHODS We studied a densely interconnected social network of 12,067 people assessed repeatedly from(More)
centered on a large database, but in this case it is entirely of living organisms, the marine bivalves. Over 28,000 records of bivalve gen-era and subgenera from 322 locations around the world have now been compiled by these authors, giving a global record of some 854 genera and subgenera and 5132 species. No fossils are included in the database, but(More)
T he decision to vote has puzzled scholars for decades. Theoretical models predict little or no variation in participation in large population elections and empirical models have typically accounted for only a relatively small portion of individual-level variance in turnout behavior. However, these models have not considered the hypothesis that part of the(More)
How did human cooperation evolve? Recent evidence shows that many people are willing to engage in altruistic punishment, voluntarily paying a cost to punish noncooperators. Although this behavior helps to explain how cooperation can persist, it creates an important puzzle. If altruistic punishment provides benefits to nonpunishers and is costly to(More)