Individually-rational collective choice

In this paper I consider the following problem: there is a collection of exogenously given socially feasible sets, and for each one of them, each one of a group of individuals chooses from an individually feasible set. The fact that the product of the individually feasible sets is larger than the socially feasible set notwithstanding, there arises no conflict between individuals. Assuming that individual preferences are random, I here characterize collective choices in terms of the way in which individual preferences must co-vary in order to explain them. I do this by combining standard revealed preference theory and its counterpart under random preferences. I also argue that there exist collective choices that cannot be rationalized, and hence that the individual rationality assumption can be refuted

Identification of individual demands from market data under uncertainty

We show that, even under incomplete markets, the equilibrium manifold identifies individual demands everywhere in their domains. Under partial observation of the manifold, we determine maximal subsets of the domains on which identification holds. For this, we assume conditions of smoothness, interiority and regularity. It is crucial that there be date-zero consumption. As a by-product, we develop some duality theory under incomplete markets

Identification of preferences from market data

We offer a new proof that the equilibrium manifold (under complete markets) identifies individual demands globally. Moreover, under observation of only a subset of the equilibrium manifold, we find domains on which aggregate and individual demands are identifiable. Our argument avoids the assumption of Balasko (2004) requiring the observation of the complete manifold

Bundling without price discrimination

This paper examines the optimal bundling strategies of a multiproduct monopoly in markets in which a seller cannot monitor and thereby restrict the purchases of buyers to a single bundle, while buyers have resale opportunities. In such markets, the standard mechanism through which bundling increases seller profits, based on price discrimination, is not feasible. The profit-maximizing bundling strategy is characterized, given the restrictions on pricing policies resulting from resale and a lack of monitoring. The welfare implications of optimal bundling are analyzed

Chemical Modifications of Lipids and Proteins by Nonthermal Food Processing Technologies

A range of nonthermal techniques have demonstrated process efficacy in ensuring product safety, extension of shelf life, and in general a retention of key quality attributes. However, various physical, chemical and biochemical effects of nonthermal techniques on macro and micro nutrients are evident, leading to both desirable and undesirable changes in food products. The objective of this review is to outline the effects of nonthermal techniques on food chemistry and the associated degradation mechanisms with the treatment of foods. Oxidation is one of the key mechanisms responsible for undesirable effects induced by nonthermal techniques. Degradation of key macromolecules largely depends on the processing conditions employed. Various extrinsic and intrinsic control parameters of high-pressure processing, pulsed electric field, ultrasound processing, and cold atmospheric plasma on chemistry of processed food are outlined. Proposed mechanisms and associated degradation of macromolecules, i.e., proteins, lipids, and bioactive molecules resulting in food quality changes are also discussed

Un modelo de predicciones diarias para contratos de futuros del azúcar

El objetivo de este trabajo es estimar el mejor modelo que permita pronosticar los precios internacionales del azúcar en los mercados de Nueva York y Londres. Para ello, se busca alguna relación de largo plazo entre la cotización diaria del WTI y los precios del azúcar en esos dos mercados. Se concluye que no existe cointegración entre estas series, lo que indica la no existencia de dicha relación en el largo plazo. Para identificar la relación en el corto plazo se estimó un VAR diferenciando las series. Se encontró que un modelo ARIMA univariado es el mejor para predecir el precio internacional del azúcargráficos, tablas.Incluye referencias bibliográficas (página 47)

Ferromagnetism in bulk Co-Zn-O

The origin of ferromagnetism in diluted magnetic semiconductors is still an open question, yielding a great deal of research across the world. This work focuses on the Co-Zn-O system. Room-temperature ferromagnetism is observed after a partial reaction of Co_3O_4 and ZnO, which can be ascribed neither to carrier mediation nor segregated cobalt metallic clusters. Another mechanism is yielding room-temperature ferromagnetism. This mechanism is associated with a partial reaction of ZnO and Co_3O_4 grains, and always appears when the starting phases (Co_3O_4 and ZnO) are present in the sample, suggesting that interfaces are involved in the origin of the observed ferromagnetism