Compositional data and Simpson's paradox

Simpson's paradox, also known as amalgamation or aggregation paradox, appears whendealing with proportions. Proportions are by construction parts of a whole, which canbe interpreted as compositions assuming they only carry relative information. TheAitchison inner product space structure of the simplex, the sample space of compositions, explains the appearance of the paradox, given that amalgamation is a nonlinearoperation within that structure. Here we propose to use balances, which are specificelements of this structure, to analyse situations where the paradox might appear. Withthe proposed approach we obtain that the centre of the tables analysed is a naturalway to compare them, which avoids by construction the possibility of a paradox.Key words: Aitchison geometry, geometric mean, orthogonal projection

Money, Fame and the Allocation of Talent: Brain Drain, the Matthew Effect and the Institution of Science

The earning structure in science is known to be flat relative to the one in the private sector, which could cause a brain drain toward the private sector. In this paper, we assume that agents value both money and fame and study the role of the institution of science in the allocation of talent between the science sector and the private sector. Following works on the Sociology of Science, we model the institution of science as a mechanism distributing fame (i.e. peer recognition). We show that since the intrinsic performance is less noisy signal of talent in the science sector than in the private sector, a good institution of science can mitigate the brain drain. We also find that providing extra monetary incentives through the market might undermine the incentives provided by the institution and thereby worsen the brain drain. Finally, we study the optimal balance between monetary and non-monetary incentives in science.

Las Topografías médicas burgalesas : 1884-1917. Un intento de contribución a la historia natural, social y sanitaria de la província de Burgos en los siglos XIX y XX

Aquest és un dels treballs de López Gómez que s'insereix en la línia d'estudi de les topografies mèdiques com a material molt útil per al¿estudi de la història de la medicina a nivell local. En aquest cas estudia les topografies mèdiques de la província de Burgos a partir de documents conservats a l¿Arxiu de la Reial Acadèmia de Medicina de Barcelona. També inclou un petit estudi sobre la biografia i obra del doctor Ildefonso Díez Santaolalla (1851-1929).

Análisis de las incoherencias entre texto e imagen en Los Simpson

En los productos audiovisuales, el canal oral y el visual transmiten información simultáneamente. Si la coherencia de sentido entre texto e imagen desaparece en el doblaje, el objetivo de verosimilitud no se satisface. En este trabajo analizo y clasifico las incoherencias texto-imagen y aporto posibles soluciones a este recurrente problema.