961 research outputs found
Catalytic Oxidation of Styrene in the Presence of Square Planar Cobalt(iii) Complexes of Polyanionic Chelating Ligands
Styrene has been catalytically oxidised in the presence of iodosoarenes and square planar cobalt(iii) complexes of
polyanionic chelating (PAC) ligands; possible intermediates in these oxygen atom transfer reactions include cobalt(v)-oxo complexes
Learning Dynamic Boltzmann Distributions as Reduced Models of Spatial Chemical Kinetics
Finding reduced models of spatially-distributed chemical reaction networks
requires an estimation of which effective dynamics are relevant. We propose a
machine learning approach to this coarse graining problem, where a maximum
entropy approximation is constructed that evolves slowly in time. The dynamical
model governing the approximation is expressed as a functional, allowing a
general treatment of spatial interactions. In contrast to typical machine
learning approaches which estimate the interaction parameters of a graphical
model, we derive Boltzmann-machine like learning algorithms to estimate
directly the functionals dictating the time evolution of these parameters. By
incorporating analytic solutions from simple reaction motifs, an efficient
simulation method is demonstrated for systems ranging from toy problems to
basic biologically relevant networks. The broadly applicable nature of our
approach to learning spatial dynamics suggests promising applications to
multiscale methods for spatial networks, as well as to further problems in
machine learning
Examining Studentsā Perceptions of Globalization and Study Abroad Programs at HBCUs
The objective in this paper is to explore studentsā perceptions of globalization and study abroad programs at Historically Black Colleges and Universities (HBCUs). Recent statistics reveal that in spite of the current growth in the number of US students receiving academic credit for their overseas academic experience, less than one percent of undergraduate minority students participate in a study abroad program during their degree program. The analysis is based on survey questionnaires administered to 263 undergraduate minority students at Alabama A&M University. The questionnaire contained questions related to respondentsā demographic characteristics and likert-scale questions pertaining to studentsā perceptions of globalization and studying abroad programs. The data are analyzed using factor analysis and binary logistic regression. The results of the regression model suggest that while a number of variables such as major and classification are found to have statistically significant relationships towards globalization, demographic variables and information source variables are not good indicators of student perceptions of globalization. One interesting findings is that with a global mindset, business students seem to be more favorably inclined toward globalization than non-business students.Globalization, Study Abroad Programs, Logistic Regression, Factor Analysis, Survey Data, Agribusiness, Agricultural and Food Policy, International Development, Research Methods/ Statistical Methods,
Effect of Foreclosure Status on Residential Selling Price: Comment
In this comment we examine the conclusion by Forgey, Rutherford, and VanBuskirk (1994) "that the foreclosed properties sold at a 23% discount," using a sample of nearly 2,000 residential property sales from the Las Vegas, Nevada area. We found that when not controlling for location with a set of dummy variables for ZIP codes, HUD foreclosed properties sold for between 12.18% and 13.96% below a random sample of properties not within one block of foreclosed properties. When controlling for location, using a set of thirty-one dummy variables for ZIP codes, the foreclosure discount fell to between 8.45% and 9.72%. When controlling for the common characteristics between foreclosed properties and their neighbors, we found foreclosure discounts are very small (between 0.17% and 2.48%) and no longer statistically significant. We conclude that foreclosure does not provide an opportunity for arbitrage profits, and this study does reinforce the findings of other studies that conclude real estate markets operate efficiently.
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