Almost by definition, radical innovations create a need to revise existing classification systems. As a result, the evolution of technological classification systems reflects technological evolution. We present three sets of findings regarding classification volatility in the U.S. Patent...

The alarming rise in drinking water pollution across the U.S. is often attributed to cost cutting pressures faced by local officials. We know little, however, about why these pressures are so severe for some cities compared to others. We present a new theory to argue that an important...

Research suggests that income inequality is inversely associated with health. This association has been documented in studies that utilize variation in income inequality across countries or across time from a single country. The primary criticism of these approaches is their inability to account...

Three causal processes have been proposed to explain associations between group income inequality and individual health outcomes, each of which implies health effects for different segments of the population. We present a novel conceptual and analytic framework for the quantitative evaluation of...

This study investigated whether state levels of social capital are associated with rates of completed suicides in the fifty U.S. states. To do this we regressed state-level suicide rates on an index of social capital, along with other variables known to influence suicide rates such as gun...

Sleep duration, associated with increased morbidity/mortality, has been shown to vary by race and occupation. Few studies have examined the additional influence of immigrant status. Using a nationally-representative sample of 175,244 US adults from the National Health Interview Survey from 2004...