Constraints and the Measurement of Freedom of Choice

This paper introduces considerations about constraints in the construction of measures of an agent's freedom. It starts with motivating the exercise from both the philosophical and the informational point of view. Then it presents two rankings of opportunity sets based on information about the extent of options and the constraints that a decision maker faces. The first ranking measures freedom as variety of choice; the second as non-restrictedness in choice.     

Regional Infrastructure and Convergence: Growth Implications in a Spatial Framework

In this paper we contribute to the debate on convergence, by presenting an overview of the catch up process of the European regions between 1995 and 2006, focusing on both absolute and conditional β convergence. Our focus is on the role of infrastructure stocks in shaping the growth and convergence process between EU regions and to what extent the spatial dimension of the data affects results. We also explicitly examine the link between infrastructure evolution and regional economic growth with a spatial panel data approach. Our results confirm an ongoing convergence process at the EU regional level, and assess the important role of transport and telecommunication infrastructure, with traditional and spatial estimation techniques. We also confirm, in a panel setting, the strong positive correlation between transport and TLC indicators and GDP growth at the regional level.     

Do infrastructures influence the convergence of efficiency in Mexico?

The aim of this study is to identify disparities in technical efficiency and the influence of infrastructure on the convergence in efficiency for the states of Mexico. It has estimated a translog production function following the model by Battese & Coelli (1995). The results show that public investment has helped increase the efficient use of factors and reveal that there are opportunities to increase the pace of growth. The analysis of convergence allows us to determine that the catching up is more intensive among groups of states, and positively influenced by the infrastructure.     

Discussing the “big n problem”

When a large amount of spatial data is available computational and modeling challenges arise and they are often labeled as “big n problem”. In this work we present a brief review of the literature. Then we focus on two approaches, respectively based on stochastic partial differential equations and integrated nested Laplace approximation, and on the tapering of the spatial covariance matrix. The fitting and predictive abilities of using the two methods in conjunction with Kriging interpolation are compared in a simulation study.     

A Cross-Cultural Exploration of the Stability of Children's Friendships and the Predictors of their Continuation

The purpose of this study was to explore cultural differences in children's perceptions of friendship quality and in the predictors of the subsequent continuation of their relationships. Participants were third and fourth-grade children in Florence, Italy, and Toronto, Canada. A total of 184 dyads of children who indicated that they were friends near the beginning of the school year completed questionnaires regarding the quality of their relationships. Among the Italian children, especially the girls, a higher proportion of friendships remained intact at the end of the school year than among the Canadians. Positive aspects of relationship quality at the first data collection point were associated with future friendship status, but earlier conflict within the dyad was unrelated to the continuation of friendship. The levels of conflict reported by the children were lower in the Italian sample than in Canada.     

Ordinal models and generalized estimating equations to evaluate disease severity

Many assays have been carried out in Capsicum spp. in order to evaluate its resistance to Phytophthora capsici , which causes blight and considerable yield loss. An assay aiming at the selection of resistant pepper and bell pepper genotypes to P. capsici was jointly performed in the laboratory of the Phytopathological Clinic of Entomology, Phytopathology and Agricultural Zoology and in the experimental area of the Plant Production Department, both located at ESALQ, University of São Paulo, Brazil. The data set for this assay comes from ordinal categorized random variables, whose analysis does not generally take into account the ordinal nature of the responses, but instead, builds indexes, among other measures, in order to evaluate the resistance of the studied genotypes. This work presents ordinal generalized linear fits in order to evaluate blight severity as well as to identify and select new resources to the pathogen. It also analyses the estimating equations proposed by Liang & Zeger (1986a, b) in order to obtain an infection pattern for the disease. From the fit of the cumulative logit models, valuable genotypes are identified for genetic breeding programs.     

Projected spending on pensions in Spain: A viability analysis

The viability of pay-as-you-go retirement pension schemes, such as that of Spain, remains a subject of ongoing debate. In this article we shall attempt to demonstrate that demography is the key variable that determines a system's viability. Analysis of several predictive studies conducted in the country shows that many of their predictions have been erroneous and their findings overpessimistic. This is because their forecasts were based on projections for the resident population, and overlooked the magnitude of the recent phenomenon of immigration. If the current influx of migrants continues, the problem of viability can be resolved.     

Characterizations and ordering properties based on log-odds functions

In this paper, we obtain some general results on characterizations of probability distributions from relationships between conditional moment, failure rate, and log-odds rate functions. We also study stochastic orders and classes based on the log-odds rate function and some relationships with usual stochastic orderings and classes. Some characterizations and ordering properties are obtained by using weighted distributions.