Observational data (i.e., data that records observations and measurements) plays a key role in many scientific disciplines. Observational data, however, are typically structured and described in ad hoc ways, making its discovery and integration diÆcult. The wide range of data collected, the variety of ways the data are used, and the needs of existing analysis applications make it impractical to...

Hydrocarbon exploration has been underway in the north of West Siberia for several decades. Giant gas fields on the Yamal Peninsula are expected to begin feeding the Nord Stream pipeline to Western Europe in late 2012. Employing a variety of highto very high-resolution satellite-based sensors, we have followed the establishment and spread of Bovanenkovo, the biggest and first field to be develo...

Abstract We develop a simple flexible-price model of business cycles driven by spikes in risk premiums. Aggregate shocks increase firms’ uninsurable idiosyncratic and raise show that can create quantitatively plausible recessions, with contractions employment, consumption, investment. Business are inefficient—output, consumption fall too much during compared to the constrained-efficient allocat...