Evolution of analogical reasoning in children: follow-up from six to eleven years old

The aim of this study is to establish the time and period of development of Analogical Reasoning (AR) and evaluate its independence and performance with respect to the age. We performed a longitudinal cohort study of two age groups and six annual follow-up phases from each one (2000-2005, 2001-2006) in six to eleven years-old children in the city of Huanuco (Peru) with a sample of 167 children (first stage), and N=121 (sixth stage). The Raven’s progressive matrices test, coloured version, was applied individually without time limits. Results indicate that AR development occurs in a constant and late way from seven to eleven years-old children, and also that there is independence between the ability of AR and the children age. We discuss the importance of knowledge in the relationships between analogies topics, adjusted to the age, as a mediating factor in the development of AR.

Los problemas de la raza en Colombia: más allá del problema racial: el determinismo geográfico y las ‘dolencias sociales’

El texto de los problemas de la raza en Colombia fue publicado en una única edición en 1920. Desde entonces, ha sido un libro que ha suscitado gran Interés Inicialmente, despertó la curiosidad de políticos, científicos e intelectuales interesados por lo que concebían entonces como los problemas de la población colombiana. Más recientemente ha atraído a académicos que, desde diferentes disciplinas, han usado esta fuente primaria para aproximarse al periodo. A pesar de los múltiples análisis que desde los años ochenta se han producido desde este texto, nos encontramos frente a una obra de gran Riqueza que sigue ofreciendo un gran potencial para futuras investigaciones la gran mayoría de los análisis existentes se han concentrado en el problema de las "razas", recalcado por el título mismo de la obra. Sin embargo, como se sugiere en el estudio introductorio, la manera como los autores concibieron la problemática social del país la cual era mucho más amplia y no se limitaba a los asuntos raciales.

Racial and spatial interaction for neighborhood dynamics in Chicago

We look at at the empirical validity of Schelling’s models for racial residential segregation applied to the case of Chicago. Most of the empirical literature has focused exclusively the single neighborhood model, also known as the tipping point model and neglected a multineighborhood approach or a unified approach. The multi-neighborhood approach introduced spatial interaction across the neighborhoods, in particular we look at spatial interaction across neighborhoods sharing a border. An initial exploration of the data indicates that spatial contiguity might be relevant to properly analyse the so call tipping phenomena of predominately non-Hispanic white neighborhoods to predominantly minority neighborhoods within a decade. We introduce an econometric model that combines an approach to estimate tipping point using threshold effects and a spatial autoregressive model. The estimation results from the model disputes the existence of a tipping point, that is a discontinuous change in the rate of growth of the non-Hispanic white population due to a small increase in the minority share of the neighborhood. In addition we find that racial distance between the neighborhood of interest and it surrounding neighborhoods has an important effect on the dynamics of racial segregation in Chicago.