Son preference, sex selection, and kinship in Vietnam

This article examines the recent rise in the sex ratio at birth in Vietnam and relates its emergence to kinship systems and ethnic composition using 2009 census micro-data. Presentation of the main socioeconomic and ethnic differentials in birth masculinity is followed by a review of the three intermediate factors leading to increases in the sex ratio at birth: prenatal technology, declining fertility, and gender bias. An indirect measurement of fertility behavior is used to demonstrate the close association between levels of the sex ratio at birth and the intensity of son preference. Data on household composition indicate that Vietnam is characterized by the co-existence of kinship patterns typical of East and Southeast Asia. Son preference in Vietnam is found to be related to the prevalence of more traditional patrilineal systems. The article concludes by considering the implications of the cultural dimensions of prenatal sex selection for policy responses and for the likely future change in the sex ratio at birth.     

A new class of probability distributions via cosine and sine functions with applications

ABSTRACT

In this paper, we introduce a new class of (probability) distributions, based on a cosine-sine transformation, obtained by compounding a baseline distribution with cosine and sine functions. Some of its properties are explored. A special focus is given to a particular cosine-sine transformation using the exponential distribution as baseline. Estimations of parameters of a particular cosine-sine exponential distribution are performed via the maximum likelihood estimation method. A simulation study investigates the performances of these estimates. Applications are given for four real data sets, showing a better fit in comparison to some existing distributions based on some goodness-of-fit tests.     

Bayesian regression under combinations of constraints

A Bayesian method for regression under several types of constraints is proposed. The constraints can be range-restricted and include shape restrictions, constraints on the value of the regression function, smoothness conditions and combinations of these types of constraints. The support of the prior distribution is included in the set of piecewise linear functions. It is shown that the proposed prior can be arbitrarily close to the distribution induced by the addition of a polynomial plus an (m−1)-fold integrated Brownian motion. Hence, despite its piecewise linearity, the regression function behaves (approximately) like an m−1 times continuously differentiable random function. Furthermore, thanks to the piecewise linear property, many combinations of constraints can easily be considered. The regression function is estimated by the posterior mode computed by a simulated annealing algorithm. The constraints on the shape and the values of the regression function are taken into account thanks to the proposal distribution, while the smoothness condition is handled by the acceptation step. Simulations from the posterior distribution are obtained by a Gibbs sampling algorithm.     

Constraint-based model for the cyclic multi-hoists scheduling problem

This article presents a method for the resolution of a material handling scheduling problem. The case studied is a real industrial problem. It consists of finding a cyclic schedule for hoist movements in a treatment surface shop. In this kind of facility, several hoists are used for all the handling operations and they have to share common zones. Then it is necessary to control that there is no collision. The mathematical formulation of the problem is based on a combination of disjunctive constraints. The constraints describe either movement schedule or collision avoidance. The resolution procedure presented identifies all the collision configurations and then uses a branch and bound-like algorithm to find the optimal solution of a given problem. The language chosen for our implementation is the constraint logic programming language: Prolog IV, which is able to solve constraints with rational variables. It actively uses the constraint propagation mechanism that can be found in several languages.     

Not by Rent Alone: Analysing the Pro‐Poor Functions of Small‐Scale Fisheries in Developing Countries

The dominant view in academic and policy arenas is increasingly one in which the major contribution of capture fisheries to development should be derived from the capacity of society to maximise the economic rent of fishery resources. Drawing upon empirical experience from the South, this article highlights the potentially disastrous consequences that a universal implementation of the rent‐maximisation model would have in developing countries, and argues that a more gradual approach would be preferable. The welfare function of small‐scale fisheries, namely, their capacities to provide labour and cash income to resource‐poor households, should be preserved until the appropriate macroeconomic conditions for rent‐maximisation and redistribution are fulfilled.     

Robust linear discriminant analysis using S‐estimators

The authors consider a robust linear discriminant function based on high breakdown location and covariance matrix estimators. They derive influence functions for the estimators of the parameters of the discriminant function and for the associated classification error. The most B‐robust estimator is determined within the class of multivariate S‐estimators. This estimator, which minimizes the maximal influence that an outlier can have on the classification error, is also the most B‐robust location S‐estimator. A comparison of the most B‐robust estimator with the more familiar biweight S‐estimator is made.     

A representation of preferences by the Choquet integral with respect to a 2-additive capacity

In the context of Multiple criteria decision analysis, we present the necessary and sufficient conditions allowing to represent an ordinal preferential information provided by the decision maker by a Choquet integral w.r.t a 2-additive capacity. We provide also a characterization of this type of preferential information by a belief function which can be viewed as a capacity. These characterizations are based on three axioms, namely strict cycle-free preferences and some monotonicity conditions called MOPI and 2-MOPI.     

On the interaction between heterogeneity and decay in two-way flow models

In this article, we examine the role played by heterogeneity in the popular ??connections model?? of Jackson and Wolinsky (J Econ Theory 71(1):355?C365, 1996). We prove that when heterogeneity with respect to the values of resources, or the information decay parameter, depends on the identity of the player who forms the link, and the player who receives the link, all networks can be supported as Nash. Moreover, we show that Nash networks may not always exist. Interestingly, in the absence of decay, neither result occurs in a model with value heterogeneity. Finally, we show that when reducing heterogeneity, all networks cannot be supported as Nash, and the non-existence problem also disappears.