Revealed cardinal preference

I prove that as long as we allow the marginal utility for money lamda to vary between purchases (similarly to the budget) then the quasi-linear and the ordinal budget-constrained models rationalize the same data. However, we know that lamda is approximately constant. I provide a simple constructive proof for the necessary and sufficient condition for the constant lambda rationalization, which I argue should replace the Generalized Axiom of Revealed Preference in empirical studies of consumer behavior.

Marriage as a Rat Race: Noisy Pre-Marital Investments with Assortative Matching

We study the incentive to invest to improve marriage prospects, in a frictionless marriage market with non-transferable utility. Stochastic returns to investment eliminate the multiplicity of equilibria in models with deterministic returns, and a unique equilibrium exists under reasonable conditions. Equilibrium investment is efficient when the sexes are symmetric. However, when there is any asymmetry, including an unbalanced sex ratio, investments are generically excessive. For example, if there is an excess of boys, then there is parental over-investment in boys and under-investment in girls, and total investment will be excessive.marriage, ex ante investments, gender differences, assortative matching tournament, sex ratio

Estimating the extent of Antarctic summer sea ice during the Heroic Age of Antarctic Exploration

In stark contrast to the sharp decline in Arctic sea ice, there has been a steady increase in ice extent around Antarctica during the last three decades, especially in the Weddell and Ross seas. In general, climate models do not to capture this trend and a lack of information about sea ice coverage in the pre-satellite period limits our ability to quantify the sensitivity of sea ice to climate change and robustly validate climate models. However, evidence of the presence and nature of sea ice was often recorded during early Antarctic exploration, though these sources have not previously been explored or exploited until now. We have analysed observations of the summer sea ice edge from the ship logbooks of explorers such as Robert Falcon Scott, Ernest Shackleton and their contemporaries during the Heroic Age of Antarctic Exploration (1897–1917), and in this study we compare these to satellite observations from the period 1989–2014, offering insight into the ice conditions of this period, from direct observations, for the first time. This comparison shows that the summer sea ice edge was between 1.0 and 1.7° further north in the Weddell Sea during this period but that ice conditions were surprisingly comparable to the present day in other sectors

Nuevos datos sobre Rushia parreyssi (Mulsant, 1856), Melandrydae Leach, 1815 y otros coleópteros interesantes de la sierra de Prades, Tarragona (Coleoptera)

En el estudio de la mortalidad de Pinus sylvestris por estrés hídrico en el área mediterránea, se ha querido ver la relación existente entre dicha mortalidad y los artrópodos, en concreto con los coleópteros. El área ibérica escogida para realizar el estudio ha sido el Tillar, situado en la sierra de Prades, en el término de Vimbodí i Poblet (Tarragona). La zona es un bosque mixto de P. sylvestris y Quercus sp. (robles y encinas) con árboles viejos y sin manejos recientes. Para conocer la fauna de coleópteros relacionados con P. sylvestris, se ha realizado una prospección exhaustiva con trampas de interceptación de vuelo, de caída y de berlese in situ. Se ha recolectado un grupo de especies de gran interés faunístico que merecen ser comentadas independientemente del proyecto.In a study on drought-induced Pinus sylvestris mortality in the Mediterranean, we explored the relationship between trees' mortality and arthropods, specifically with beetles. The Iberian area chosen for the study was the Tillar, located in the Sierra de Prades, nearby Vimbodí i Poblet (Tarragona). The area is in a mixed forest of P. sylvestris and Quercus sp. (oaks), including old trees and without any recent management. In order to study the fauna of beetles associated with P. sylvestris, we carried out a comprehensive survey by using flight interception traps, pitfall trap and in situ Berlese traps. We recovered a very interesting group of species which deserve to be discussed independently of the project