Evan Johnson

Do Important Inventions Benefit from Knowledge Originating in Other Technological Domains

A frequently made claim in the innovation literature is that important inventions involve the transfer of new knowledge from one technological domain to another. This study uses U.S. patents granted from 1976 to 2006 to identify the role of knowledge acquired from outside each patents technological domain. Our results do not seem to support the claim above. Increasing citations to external prior art is a significantly less important predictor of forward citation frequency than citing prior art that is technologically closer. This result is robust across several model specifications and ways of defining whether each flow of knowledge is external. The result is even stronger in the most highly cited technology categories. We discuss possible explanations for this apparently negative impact of external knowledge—including both measurement issues and challenges associated with assimilating disparate knowledge.

Willingness to Pay for Climate Policy: A Review of Estimates

One explanation for the modest pace of efforts to mitigate climate change, both federally and internationally, is that constituents do not ascribe much beneficial value to new laws that change the way we produce and consume energy. We surveyed estimates of consumer willingness to pay (WTP) for climate policy to: (1) assess the validity of this explanation, (2) compare elicitation techniques, and (3) explore factors that might explain variation in WTP estimates. We recalculated WTP estimates on an equivalent basis across 27 studies and found a range for WTP of

Multiscale discontinuous galerkin methods for coupled MHD-kinetic plasma simulations

22-

Gaussian-Moment Relaxation Closures for Verifiable Numerical Simulation of Fast Magnetic Reconnection in Plasma

437/household annually, with a median of

Zero-Range Effective Field Theory for Resonant Wino Dark Matter

135. We also discuss outliers not included in this range. Discrepancies among estimates drawn from American, Asian, and European samples enable some preliminary inferences about the effects of nationality on WTP for climate stability. Environmental attitudes and beliefs are common explanatory elements in WTP surveys. Others include income, education, and political views. While valuation methods and survey types vary, the great majority of existing work in this area has relied on contingent valuation.

Wino dark matter annihilation through the radiative formation of bound states

A multiscale algorithm is developed in this study in which the ideal MHD equations is coupled with a two-fluid or a fully kinetic model to correctly model magnetic reconnection that is a common phenomena in the magnetosphere and in laboratory plasmas. In this approach, special Riemann solvers are constructed in such a way as to minimize spurious reflections at the model interface. The proposed method is validated on several test cases of waves propagating through the model interface.