Statistical Evidence of Mortgage Redlining? A Cautionary Tale

Statistical analyses of mortgage redlining at the neighborhood level have fueled the debate over the existence of racial redlining in mortgage lending, both "proving" and "disproving" that redlining exists, depending upon the type of model used. In this paper, we compare results of different statistical models using data for the Washington, DC metropolitan area to determine their usefulness in providing statistical evidence on this issue. After demonstrating the sensitivity of single-equation models to specification error, we estimate a simultaneous equations model of mortgage credit flows. This model makes it possible to analyze differences in the supply and demand for mortgage credit by the racial composition of the community. We conclude that most, if not all, statistical evidence of racial redlining based on aggregate loan data is at best inconclusive, and more likely, misleading.

The spatiotemporal pattern of earthworm community in the grass savannas of Lamto (Ivory Coast): The spatiotemporal pattern of earthworm community in the grass savannas of Lamto (Ivory Coast)

The impact of earthworms on both soil physical properties and soil organic matter dynamics has been well documented (Lavelle and Spain 2001). There is a wealth of literature dedicated to the biological mechanisms at work or to empirical approaches based on field data. Assessing the functional role of a species or community implies establishing both time and space scales at which it is effectively the primary determinant of the process(es) at hand. In that context, space-time data analyses are powerful tools to process community data collected on numerous occasions but are, however, not widely disseminated in the community of ecologists. Although computer resources are available, one difficulty is that ad hoc field data are not always easily available which hinders thepercolation of the methods

Coherent beam superposition of ten diode lasers with a Dammann grating

We demonstrate the use of a binary diffractive optical element in a very simple setup to convert the multilobed beam from a low fill factor array of coherent laser diodes into a quasi-Gaussian beam. The phase profile of the grating is determined with a phase retrieval algorithm. Experimentally, the conversion efficiency reaches more than 44%. We also establish that this setup can be used to make an effective measurement of the coherency of the laser array

Taxing consumption in unequal economies

El presente trabajo muestra que los impuestos lineales sobre el consumo son una herramienta potente para lograr una redistribución eficiente. Este es el resultado que se obtiene en un modelo cuantitativo de ciclo de vida que replica la distribución de la renta y de la riqueza en Estados Unidos. Una política óptima exige recaudar todos los ingresos fiscales a través del consumo y llevar a cabo la redistribución mediante una escala de tipos muy progresivos del impuesto sobre la renta. Las rentas de capital y la riqueza deberían estar exentas de tributación. Esta política reduce la desigualdad y aumenta la productividad, además de aportar grandes ganancias de bienestar en comparación con el statu quo. Alrededor de dos tercios de estas ganancias se deben a la redistribución. Por último, la reforma propuesta en este trabajo también mejora el bienestar a corto plazoThis paper shows that linear consumption taxes are a powerful tool to implement efficient redistribution. We derive this result in a quantitative life-cycle model that reproduces the distribution of income and wealth in the United States. Optimal policy calls for raising all fiscal revenues from consumption, and providing redistribution via a highly progressive wage tax schedule. Capital income and wealth should not be taxed. This policy reduces inequality and increases productivity, and brings large welfare gains relative to the status quo. Around two-thirds of these gains are due to redistribution. Finally, our reform is also welfare improving in the short-run

Marginal tax changes with risky investment

Este trabajo utiliza un modelo de ciclo de vida para cuantificar el rol de la heterogeneidad en los rendimientos de las inversiones en la respuesta económica de unos cambios impositivos marginales. En este modelo, los agentes que son suficientemente productivos pueden obtener rendimientos más altos si eligen ser empresarios. La heterogeneidad en los rendimientos amplifica la respuesta de los ingresos totales a los cambios impositivos marginales sobre toda la distribución del ingreso. El 1 % más rico muestra las elasticidades más altas. La heterogeneidad de retorno aumenta los incentivos a invertir para los empresarios más ricos y de alto rendimiento, amplificando así sus respuestas de ingresos a los cambios del impuesto marginal. Esta reasignación de capital aumenta la productividad agregada, generando un mayor impulso en los salarios de equilibrio. Esto, a su vez, fortalece la respuesta del ingreso del 90 % más pobre, pero, sin embargo, su respuesta es menor que en la parte superior de la distribución.Using an estimated life-cycle model, we quantify the role of heterogeneity in wealth returns for the response of income to marginal tax changes. In our economy, agents who are sufficiently productive can obtain higher returns by choosing to be entrepreneurs. Return heterogeneity amplifies the responsiveness of total income to marginal tax changes along the entire income distribution with the top 1 percent displaying the highest elasticities. Return heterogeneity increases the incentives to invest for the richest, highreturn entrepreneurs, thus amplifying their income responses to marginal tax changes. This reallocation of capital increases aggregate productivity, generating a larger boost in equilibrium wages. This in turn strengthens the income response of the bottom 90 percent, but nevertheless, their response is smaller than at the top

Interview of John P. Rossi, Ph.D.

Dr. John Patrick Rossi was born in Philadelphia in 1936 to Gabriel (Al) and Muriel Rossi. He was raised by two aunts, an uncle, and his grandfather in lower Olney. He attended La Salle College High School, received his B. A. in history from La Salle College in 1958, his M. A. from Notre Dame in 1960, and his Ph.D. in History from the University of Pennsylvania in 1965. His dissertation was on the British Liberal Party from 1874 to 1880. He began teaching at La Salle College in 1962; was associate editor of Four Quarters ; received the Lindback Award; developed popular classes on World War II, baseball history, and George Orwell; and served as History Department chair. He has published many works on the British Liberal Party, baseball history, Orwell, and other topics. After retiring, he received the honorable title Professor Emeritus

Plant row and soil factors influencing the microspatial patterns of plant-parasitic nematodes on sugarcane in Martinique

Le but de cette étude a été de comparer la micro-répartition de différentes espèces de nématodes phytoparasites et la densité racinaire de plants de canne à sucre, en relation avec le rang et certains paramètres édaphiques, sur un ferrisol caractérisé par trois niveaux de remodelage. Les échantillons de sol et de racine ont été prélevés sur une grille à maille régulière disposée entre deux rangs de canne à sucre. Dans la situation profondément remodelée, où les teneurs en carbone, azote et potassium sont les plus faibles, #Pratylenchus zeae présente une structure spatiale liée au rang de canne. #Helicotylenchus erythrinae montre cette répartition particulière dans les trois situations. Au contraire, #Criconemella onoensis ne montre pas de distribution particulière vis-à-vis du rang et de la quantité de racine et ce, quelle que soit la situation. #Hemicriconemoides cocophillus apparaît disposé en lignes parallèles au rang de canne, dans la direction de la pente. Les répartitions spatiales sont représentées graphiquement et analysées à l'aide de semi-variogrammes afin de confirmer et de caractériser les structures observées. L'utilisation de semi-variogrammes croisés montre des interactions antagonistes entre #C. onoensis$ et les autres espèces. Ces interactions sont plus importantes dans la situation profondément remodelée. En fonction de l'intensité du remodelage et des variations consécutives des paramètres du sol, les répartitions et interactions entre nématodes phytoparasites varient quantitativement et qualitativement. (Résumé d'auteur

Interview of John P. Rossi, Ph.D.

This interview examines Dr. John Rossi’s life since his formal retirement in 2006. Major topics in the interview include Dr. Rossi’s publication of the La Salle history book, Living the Promise. Rossi details the archival experience, the research, drafts, and publication of the book. He also discusses the book’s reception at the school, as well as the community. Another major topic that was explored was Dr. Rossi’s travels and experience in Great Britain while he was researching his doctoral dissertation in the 1960s. Other topics include his analysis of history and his perspective on how technology has affected the classroom and teaching experience. Dr. Rossi also describes his reaction and the process of being granted the title of professor emeritus in 2006. Finally, his post-retirement life is explored; he continues to remain connected to the university through his teaching, as well as several writing projects that he is involved with

Structurally Conserved Interaction of Lgl Family with SNAREs Is Critical to Their Cellular Function

The Lethal giant larvae (Lgl) tumor suppressor family is conserved from yeast to mammals and plays a critical yet controversial role in cell polarity. Studies on Drosophila Lgl suggest that its function in polarity is through regulation of the acto-myosin cytoskeleton. In contrast, studies on the yeast Lgl homologs, Sro7/Sro77, suggest a function in exocytosis through interaction with the t-SNARE Sec9. Using yeast/mammalian Lgl chimeras, we demonstrate that the overall architecture of Lgl proteins is highly conserved and that the C-terminal domain is the major site of SNARE interaction within both yeast and mammalian homologs. Importantly, we find that the ability of Lgl chimeras to function as the only source of Lgl in yeast correlates precisely with the ability to interact with the yeast t-SNARE. We report a novel interaction between Sro7 and the yeast myosin V, Myo2. However, we find that interactions with either Myo2 or Myo1 (myosin II) cannot account for the dramatic functional differences observed for these chimeras in yeast. These results provide the first demonstration that the interaction of an Lgl family member with a specific effector is critical to its function in vivo. These data support the model that the Lgl family functions in cell polarity, at least in part, by regulating SNARE-mediated membrane delivery events at the cell surface

Physiological complexity of EEG as a proxy for dementia risk prediction: a review and preliminary cross-section analysis

The aim of this work is to give the readers a review (perspective) of prior work on this kind of complexity-based detection from resting-state EEG and present our preliminary cross-section analysis results on how EEG complexity of supposedly healthy senior persons can serve as an early warning to clinicians. Together with the use of wearables for health, this approach to early detection can be done out of clinical setting improving the chances of increasing the quality of life in seniors.Comment: 19 pages, 1 figure, 1 tabl