Building research skills in the Macalester economics major

Economics majors at Macalester College have won numerous awards for their research papers, and this success has helped them land jobs in finance, consulting, and the nonprofit sector, as well as gain admission to top graduate programs. This article describes how the Economics Department at Macalester promotes economic research among its students

PROFITABILITY OF GEOGRAPHIC DIVERSIFICATION STRATEGY

Agribusiness,

Pilferers or Paladins? Russia's Managers in Transition

http://deepblue.lib.umich.edu/bitstream/2027.42/39408/3/wp17.pd

Enterprise Restructuring in Russia's Transition Economy: Formal and Informal Mechanisms

This paper examines the nature and scope of enterprise restructuring in Russia using two sources of firm-level data. The first involves a panel of over 2,000 civilian manufacturing firms in Moscow, Tver, Volgograd, Rostov, and Novosibirsk. The second involves data collected from a series of in-depth interviews conducted between 1994 and 1997 with top-level managers in 47 firms located in Moscow, Tver, Nizhny Novgorod, and Novosibirsk. The objective of the paper is threefold. First, we summarize the existing literature on enterprise restructuring, and evaluate the pros and cons of a number of restructuring measures that have been used in studies of privatized firms in Russia and other transition economies. Second, we apply two measures of enterprise restructuring to our data to investigate the extent of variation by industry, ownership structure, and location. Third, we examine in detail the question of whether barter enhances or impedes enterprise restructuring in Russia.http://deepblue.lib.umich.edu/bitstream/2027.42/39541/3/wp152.pd

Developing an improved biomonitoring tool for fine sediment: combining expert knowledge and empirical data

AbstractThe Proportion of Sediment-sensitive Invertebrates (PSI) index is a biomonitoring tool that is designed to identify the degree of sedimentation in rivers and streams. Despite having a sound biological basis, the tool has been shown to have only a moderate correlation with fine sediment, which although comparable to other pressure specific indices, limits confidence in its application. The aim of this study was to investigate if the performance of the PSI index could be enhanced through the use of empirical data to supplement the expert knowledge and literature which were used to determine the original four fine sediment sensitivity ratings. The empirical data used, comprised observations of invertebrate abundance and percentage fine sediment, collected across a wide range of reference condition temperate stream and river ecosystems (model training dataset n=2252). Species were assigned sensitivity weights within a range based on their previously determined sensitivity rating. Using a range of weights acknowledges the breadth of ecological niches that invertebrates occupy and also their differing potential as indicators. The optimum species-specific sensitivity weights were identified using non-linear optimisation, as those that resulted in the highest Spearman's rank correlation coefficient between the Empirically-weighted PSI (E-PSI) scores and deposited fine sediment in the model training dataset. The correlation between percentage fine sediment and E-PSI scores in the test dataset (n=252) was eight percentage points higher than the correlation between percentage fine sediment and the original PSI scores (E-PSI rs=−0.74, p<0.01 compared to PSI rs=−0.66, p<0.01). This study demonstrates the value of combining a sound biological basis with evidence from large empirical datasets, to test and enhance the performance of biomonitoring tools to increase confidence in their application

Detachment energies of spheroidal particles from fluid-fluid interfaces

The energy required to detach a single particle from a fluid-fluid interface is an important parameter for designing certain soft materials, for example, emulsions stabilised by colloidal particles, colloidosomes designed for targeted drug delivery, and bio-sensors composed of magnetic particles adsorbed at interfaces. For a fixed particle volume, prolate and oblate spheroids attach more strongly to interfaces because they have larger particle-interface areas. Calculating the detachment energy of spheroids necessitates the difficult measurement of particle-liquid surface tensions, in contrast with spheres, where the contact angle suffices. We develop a simplified detachment energy model for spheroids which depends only on the particle aspect ratio and the height of the particle centre of mass above the fluid-fluid interface. We use lattice Boltzmann simulations to validate the model and provide quantitative evidence that the approach can be applied to simulate particle-stabilized emulsions, and highlight the experimental implications of this validation