Population and Deforestation in Costa Rica

This paper addresses a central debate in research and policy on population and environment, namely the extent to which rapid population growth is associated with the massive deforestation currently underway in the tropics. We utilize the experience of Costa Rica during the last forty years to illustrate what the main issues are, discuss the history of deforestation in that country, and present results from conventional regression methods and from the application of spatial analyses. These analyses enable us to estimate the magnitude of the relation between population and deforestation and to identify the factors that are responsible for the linkage between them.     

On the Measurement of Interpersonal Trust Transfer: Proposal of Indexes

This paper investigates the measurement of trust transfer in interpersonal contexts. Despite the importance of this topic, little evidence of comparable indicators exists to fill the current gap in knowledge regarding the measurement of interpersonal transference of trust and its reciprocal. We propose a modification of the classical structure of a widely accepted experimental setting for analyzing trust (i.e. a trust game) and build two indexes for the measurement of trust transfer and its reciprocation. Several properties of these indicators are investigated to examine their robustness and accuracy for measuring the transference of interpersonal trust. Furthermore, using data from our own modified trust game, we provide an empirical examination of both indexes. The results show that the existence of a mutually known third party fosters a stronger willingness to achieve cooperative behavior in an anonymous trust game; thus, the transference of interpersonal trust works in both directions of the dyad.     

CONTESTS WITH DRAWS: AXIOMATIZATION AND EQUILIBRIUM

We introduce and axiomatize a class of single‐winner contest success functions that embody the possibility of a draw. We then analyze the game of contest that our success functions induce, having different prizes delivered in the occurrence of a win and a draw. We identify conditions for the existence and uniqueness of a symmetric interior Nash equilibrium and show that equilibrium efforts and equilibrium rent dissipation can be larger than in a Tullock contest (with no possibility of a draw) due to increased competition even if the draw‐prize is null. These results suggest that a contest designer may profit from introducing the possibility of a draw. Finally, we show that this approach naturally extends to multiprize contests with multiple draws across different subsets of the set of players. (JEL C72, D72, D74)     

Altruism and monetary transfers in the household: inter- and intra-generation issues

The literature on altruism and monetary transfers in the household is here extended with new and recent evidence on different approaches with the final aim being to provide policy recommendations in order to reduce socio-economic inequality among households, from both inter- and intra-generational perspectives. Thus, we include issues which deal with transfers from parents to kids (downstream transfers), and with transfers from kids to parents (upstream transfers). On the other hand, we also include issues from intragenerational transfers beyond the household, studying such phenomena as charitable donations and remittances from migrants.     

Structure and composition of woody plants in urban forest remnants with different adjacent land-use and slope aspect

The plant community in the karst forest is influenced by mesoclimatic conditions, such as temperature and humidity and these conditions are in turn influenced by topographic features. Urban areas adjacent to karstic forest remnants also have the potential to influence mesoclimatic variables and may serve as a source of exotic species. We described the temperature and relative humidity of karstic forest remnants at slopes with combinations of either southeast (SE) or northwest (NW) aspect, and adjacent to either urban (URB) or secondary forest (SF). We also compared forest structure and composition on these slopes to understand the interaction between forest aspect and adjacent land use on the plant community. URB-SE slopes had highest temperature and lowest humidity among all adjacent land use-aspect combinations. Understory species in SE slopes had similar richness and diversity independently of adjacent land use, however within NW aspect, slopes adjacent to urban areas showed higher values than slopes adjacent secondary forest. Canopy trees species in slopes adjacent to secondary forest were more diverse and rich in SE than in NW, although no differences between aspects were detected within URB-adjacent slopes. Understory species composition was different among the four land use-aspect combinations. However, composition of canopy trees species was different only between aspect types. Most exotic species in the sites were associated with previous agricultural practices and not with current land use. Our results show a temporal and spatial influence of anthropogenic systems on the plant community in karstic forest remnants at a suburban area of Puerto Rico.     

A Bayesian model for estimating the malaria transition probabilities considering individuals lost to follow-up

It is known that patients may cease participating in a longitudinal study and become lost to follow-up. The objective of this article is to present a Bayesian model to estimate the malaria transition probabilities considering individuals lost to follow-up. We consider a homogeneous population, and it is assumed that the considered period of time is small enough to avoid two or more transitions from one state of health to another. The proposed model is based on a Gibbs sampling algorithm that uses information of lost to follow-up at the end of the longitudinal study. To simulate the unknown number of individuals with positive and negative states of malaria at the end of the study and lost to follow-up, two latent variables were introduced in the model. We used a real data set and a simulated data to illustrate the application of the methodology. The proposed model showed a good fit to these data sets, and the algorithm did not show problems of convergence or lack of identifiability. We conclude that the proposed model is a good alternative to estimate probabilities of transitions from one state of health to the other in studies with low adherence to follow-up.     

A process capability index with reliable confidence intervals

A well-know process capability index is slightly modified in this article to provide a new measure of process capability which takes account of the process location and variability, and for which point estimator and confidence intervals do exist that are insensitive to departures from the assumption of normal variability. Two examples of applications based on real data are presented.