RACIAL MINORITIES IN U.S. HISTORY TEXTBOOKS: A CASE FOR A MORE SYSTEMATIC APPROACH TO TEXTBOOK EVALUATION

A few decades ago, textbook adoption proceedings were relatively dull affairs. Present at these meetings were political, business, and labor interest group representatives who were primarily concerned with the treatment their constituencies received in textbooks, especially social studies texts. Expressing common concerns, board members and traditional interest group representatives only occasionally debated what ought to be included in social studies texts. The dealings rarely bordered on the sensational and, in most cases, resulted in minimal discussion and acceptance of texts recommended for adoption by a board\u27s textbook committee

A comparison of general-purpose optimization algorithms forfinding optimal approximate experimental designs

Several common general purpose optimization algorithms are compared for findingA- and D-optimal designs for different types of statistical models of varying complexity,including high dimensional models with five and more factors. The algorithms of interestinclude exact methods, such as the interior point method, the Nelder–Mead method, theactive set method, the sequential quadratic programming, and metaheuristic algorithms,such as particle swarm optimization, simulated annealing and genetic algorithms.Several simulations are performed, which provide general recommendations on theutility and performance of each method, including hybridized versions of metaheuristicalgorithms for finding optimal experimental designs. A key result is that general-purposeoptimization algorithms, both exact methods and metaheuristic algorithms, perform wellfor finding optimal approximate experimental designs

Illegal immigration and a heterogeneous labour force. When can quotas generate an internal conflict?

In this paper we analyze the effects on the welfare of heterogeneous native workers in the context of the presence of legal and illegal immigrants, and where the main instrument of economic policy takes the form of entry quotas. In the framework of a model of overlapping generations, we find that these effects are not monotonous. More particularly, we note that in certain circumstances the effects on the native workers of a change in the quota are opposite in nature, depending on whether or not these workers are qualified. The key aspect of this result is, on the one hand, the effect of illegal immigration on wages and, on the other, the part of income generated by the illegal immigrants that is appropriated by the natives for managing this “informal” labour market. Keywords: Illegal immigration; entry quotas; qualification. JEL: F22, J61,J68.

Democracias Postransicionales Centroamericanas. ¿Hacia la Consolidación?

Comunicación presentada en el VII Congreso Internacional de Estudios Latinoamericanos América Latina en el Nuevo Siglo, celebrado del 9 al 12 de Noviembre de 2004 en la Universidad Nacional de Costa Rica. Trata sobre la consolidación democrática en los países centroamericanos que han transitado hacia la democracia en los años 90, El Salvador, Guatemala y Nicaragua

Alternative method for the metrological characterization of spur gears in the sub-millimeter range using optical equipment

The aim of this work is to develop a software that allows the inspection of spur gear manufactured in the sub-millimeter range. The measurements are made using a digital optical machine and using an analysis proprietary software implemented in Matlab®, which is able to handle images, captured using the digital optical machine. The software allows to evaluate the profile and pitch deviations as establish in the ISO/TR 10064-1:1992 standar

La Relación con la Unión Europea como Factor de Consolidación de las Democracias Postransicionales Centroamericanas

En los años noventa, tras el fin de las guerras civiles que asolaron el istmo centroamericano, sobre todo El Salvador, Guatemala y Nicaragua, y tras los procesos de transición, se ha pasado a un contexto de paz y democracia, al menos formal. Ningún autor niega el importante paso dado en estos años y todos se congratulan del fin de los conflictos armados en la región, pero estas democracias no dejan de ser inestables. Es por esta inestabilidad por lo que la consolidación de la democracia se ha convertido en un factor clave de análisis del futuro y en una necesidad imperiosa de estos países, como lo fue en su momento para otros que también vivieron procesos de transición, como Portugal, España y Grecia en la Europa Meridional. El gran problema para esta consolidación es que Centroamérica no cuenta con un actor externo que proporcione estabilidad y apoyo económico a su desarrollo, como si tuvieron los países del sur de Europa en la entonces Comunidad Económica Europea, que funcionó, como señalan la mayor parte de autores, como factor de consolidación de lo que entonces eran democracias inestables políticamente y en aguda crisis económica. Centroamérica no ha podido contar con una ayuda similar en su entorno, EEUU, la gran potencia continental, se ha dedicado más a defender sus intereses económicos en la zona que a tener en cuenta los problemas regionales