Showing 581 - 590 of 733 Items

NASSR Caucus: Introduction

Date: 2021-01-01

Creator: David Collings

Access: Open access



Social Science and the Analysis of Environmental Policy

Date: 2020-09-01

Creator: Cary Coglianese, Shana M. Starobin

Access: Open access

As much as environmental problems manifest themselves as problems with the natural environment, environmental problems—and their solutions—are ultimately social and behavioral in nature. Just as the natural sciences provide a basis for understanding the need for environmental policy and informing its design, the social sciences also contribute in significant ways to the understanding of the behavioral sources of environmental problems, both in terms of individual incentives and collective action challenges. In addition, the social sciences have contributed much to the understanding of the ways that laws and other institutions can be designed to solve environmental problems. In this review article, we distill core intellectual frameworks from among the social sciences that scaffold modern environmental policy in industrialized country contexts—focusing on key contributions principally from political science, economics, psychology, and sociology to the analysis of environmental problems and their solutions. These frameworks underlie how environmental problems are defined at multiple scales and the conceptualization and empirical testing of policy solutions that seek to shape human behavior in ways that improve environmental quality and promote sustainable economic growth. With the planet facing continued environmental threats, improving environmental policy decision-making depends on the insights and frameworks of social science research in addition to those of the natural sciences.


2018 Table of static dipole polarizabilities of the neutral elements in the periodic table*

Date: 2019-06-18

Creator: Peter Schwerdtfeger, Jeffrey K. Nagle

Access: Open access

A 2018 update of the most accurate calculated and experimental static dipole polarizabilities of the neutral atoms in the Periodic Table from nuclear charge Z = 1 to 120 is given. Periodic trends are analyzed and discussed.


Estimating the Impact of Ride-Hailing App Company Entry on Public Transportation Use in Major US Urban Areas

Date: 2019-01-01

Creator: Erik Nelson, Nicole Sadowsky

Access: Open access

Since 2011, the private ride-hailing (RH) app companies Uber and Lyft have expanded into more and more US urban areas. We use a dynamic entry event study to examine the impact of Uber and Lyft's entry on public transportation (PT) use in the United States' largest urban areas. In most cases, entry into urban areas was staggered: Uber entered first, followed several months later by Lyft. We generally find that PT use increased in the representative urban area, all else equal, immediately following first RH app company entry. However, this spike in PT use largely disappeared following the entry of the second RH app company. Slightly different RH app company-PT use relationships emerge when we estimate the PT use model over various subsets of urban areas and PT modes.


The likelihood of local allies free-riding: Testing economic theories of alliances in US counterinsurgency interventions

Date: 2017-09-01

Creator: Barbara Elias

Access: Open access

In counterinsurgency interventions, free-riding by small, local allies is persistent. Yet, the literature on free-riding by small allies is largely limited to conventional multilateral partnerships, such as the North Atlantic Treaty Organization, neglecting other types of asymmetric alliances. Using new data containing 144 US requests to local allies in Vietnam, Iraq and Afghanistan, this article tests the logic of economic theories of alliances in counterinsurgency interventions. I find even when small allies are explicitly asked to contribute to alliance-wide security goods, they are likely to free-ride almost half the time (45%), and the likelihood of free-riding is dependent on whether local allies can be excluded by larger allies. This conclusion upholds the logic of economic models, since shared defense goods that exclude local allies fail to meet the criteria of public goods.


New insights on obtaining phytoplankton concentration and composition from in situ multispectral Chlorophyll fluorescence

Date: 2010-01-01

Creator: Christopher W. Proctor, Collin S. Roesler

Access: Open access

A three-channel excitation (435 nm, 470 nm, and 532 nm) Chlorophyll fluorometer (695 nm emission) was calibrated and characterized to improve uncertainty in estimated in situ Chlorophyll concentrations. Protocols for reducing sensor-related uncertainties as well as environmental-related uncertainties were developed. Sensor calibrations were performed with thirteen monospecific cultures in the laboratory, grown under limiting and saturating irradiance, and sampled at different growth phases. Resulting uncertainties in the calibration slope induced by natural variations in the in vivo fluorescence per extracted Chlorophyll yield were quantified. Signal variations associated with the sensors (i.e., dark current configurations, drift, and stability) and the environment (i.e., temperature dependent dark currents and contamination by colored dissolved organic matter [CDOM] fluorescence) yielded errors in estimating in situ Chlorophyll concentration exceeding 100%. Calibration protocols and concurrent observations of in situ temperature and CDOM fluorescence eliminate these uncertainties. Depending upon excitation channel, biomass calibration slopes varied between 6-and 10-fold between species and as a function of growth irradiance or growth phase. The largest source of slope variability was due to variations in accessory pigmentation, and thus the variance could be reduced among pigment-based taxonomic lines. Fluorescence ratios were statistically distinct among the pigment-based taxonomic groups, providing not only a means for approximating bulk taxonomic composition, but also for selecting the appropriate calibration slope to statistically improve the accuracy of in situ Chlorophyll concentration estimates. Application to 5 months of deployment in China Lake, Maine, USA reduced the error in estimating extracted Chlorophyll concentration from > 30% to < 6%. © 2010, by the American Society of Limnology and Oceanography, Inc.


Accounting for creativity: Lessons from the economic history of intellectual property and innovation

Date: 2020-01-01

Creator: B. Zorina Khan

Access: Open access

Social progress depends on the realization of inventive ideas, and economic history provides valuable lessons about creativity in technology and culture. The empirical study of over one hundred thousand innovative individuals who obtained patents, copyrights, and prizes, sheds light on the relationship between institutions, incentives, and transformative ideas and expression, over the past two centuries. The European growth model assumed useful knowledge was scarce, and top-down administered innovation systems offered rights and rewards to “exclusive” groups. By contrast, American policies regarded creativity as widely distributed in the general population, and further promoted “inclusive” market-oriented mechanisms that fostered diversity in ideas and outcomes. The evidence suggests that property rights in patents facilitated markets in ideas, and ensured that returns were aligned with productivity and market demand. Whereas, such administered systems as innovation prizes and publisher’s copyrights in the “creative industries” benefited the few rather than overall social welfare.


Framing Social Media and Organizations

Date: 2013-04-12

Creator: Dhiraj Murthy

Access: Open access



Role of iron and organic carbon in mass-specific light absorption by particulate matter from louisiana coastal waters

Date: 2012-01-01

Creator: Margaret L. Estapa, Emmanuel Boss, Lawrence M. Mayer, Collin S. Roesler

Access: Open access

We investigated the influences of organic content and mineralogical composition on light absorption by mostly mineral suspended particles in aquatic and coastal marine systems. Mass-specific absorption spectra of suspended particles and surface sediments from coastal Louisiana and the lower Mississippi and Atchafalaya rivers were measured with a centered sample-mount integrating sphere and analyzed in conjunction with organic carbon (OC), hydrochloric acid- (HCl-) extractable iron, and dithionite-extractable iron contents. Compositions and absorption properties were comparable to published values for similar particles. Dithionite-extractable iron was strongly correlated with absorption at ultraviolet (UV) and blue wavelengths, while OC and HCl-extractable iron were weakly but positively correlated. Oxidative removal of OC from sediments caused small and variable changes in absorption, while dithionite extraction of iron oxides strongly reduced absorption. Shoulders in the absorption spectra corresponded to absorption bands of iron oxide minerals, and their intensities were well correlated to dithionite-extractable iron contents of the samples. These findings support a primary role for iron oxide and hydroxide minerals in the mass-specific absorption of mostly inorganic particles from the terrestrially influenced coast of Louisiana. Riverine particles had higher dithionite-extractable iron contents and iron oxide- specific absorption features than did marine particles, consistent with current knowledge regarding differential transport of particulate iron oxides and hydroxides through estuarine salinity gradients and reductive alteration of these oxide phases on the Louisiana shelf. The quantifiable dependence of UV absorption features on iron oxide content suggests that, under certain conditions, in situ hyperspectral absorption measurements could be designed to monitor water-column iron mineral transport and transformation. © 2012, by the Association for the Sciences of Limnology and Oceanography, Inc.


US Household Demand for Organic Fruit

Date: 2017-08-31

Creator: Erik Nelson, John M Fitzgerald, Nathan Tefft, John L. Anderson

Access: Open access

We estimate US household monthly elasticities of demand for some of the more popular organic fruits. To our knowledge, this is the first US-wide, multi-year analysis of price and income elasticities for various organic fruits. We calculate elasticities of demand for low-income, middle class, and rich income bracket households using three estimation techniques: two econometric methods and one machine learning method (least absolute shrinkage and selection operator (LASSO)). Demand estimates are based on Nielsen scanner data from approximately 60,000 households collected from 2011 to 2013. Generally, we find that own-price conditional and unconditional elasticities of demand for organic fruits are negative. Unconditional elasticity magnitudes tend to be largest in the representative middle-class household. Income elasticities of demand measurements are inconsistent and often statistically insignificant. This finding is consistent with the survey literature finding that many consumers buy organic food for mostly moral or ethical reasons. We run two policy experiments: a 10% subsidy of organic fruits, and a 10% tax on conventional fruits. Our hypothetical policies engender a stronger reaction among the general public than habitual buyers of organic fruit; unconditional purchase and expenditure elasticities are generally larger than conditional purchase and expenditure elasticities. Finally, we find that elasticities measured with the LASSO technique are not radically different than those measured with econometric methods. The most noticeable difference between the two analytical techniques is that LASSO is more likely to find price and income elasticities of demand that indistinguishable from zero, both substantively and statistically.