Student-t censored regression model: properties and inference

In statistical analysis, particularly in econometrics, it is usual to consider regression models where the dependent variable is censored (limited). In particular, a censoring scheme to the left of zero is considered here. In this article, an extension of the classical normal censored model is developed by considering independent disturbances with identical Student-t distribution. In the context of maximum likelihood estimation, an expression for the expected information matrix is provided, and an efficient EM-type algorithm for the estimation of the model parameters is developed. In order to know what type of variables affect the income of housewives, the results and methods are applied to a real data set. A brief review on the normal censored regression model or Tobit model is also presented.     

The Role of Active Listening in Teacher–Parent Relations and the Moderating Role of Attachment Style

This study tested the perceived effectiveness of “Listening-Ask questions-Focus on the issue–Find a first step” method (McNaughton et al., 2008) in a parent–teacher conversation using a scenario study (N?=?208). As expected, a scenario based on this method compared with a scenario of a conversation omitting the four steps of the method was perceived both by teachers and parents as more effective (d?=?1.43). Moreover, it was hypothesized that the effectiveness of this listening method would be found largely among secure participants. Indeed, the findings suggested that anxious people were less sensitive to the manipulation. Research hypotheses regarding avoidant attachment style were not supported, suggesting that more research is needed to better understand the moderating role of attachment style.     

Cohabitation in Spain: No Longer a Marginal Path to Family Formation

Although many indicators reflect the marked retreat from marriage occurring in Spain since the 1980s, the diffusion of cohabitation has been slow. The confluence of very low and late fertility, latest‐late marriage, and low cohabitation has been largely regarded as defying the predictions of the second demographic transition and has fueled a debate over the distinctiveness of the Mediterranean model of family formation. Comparative analyses based on the Family and Fertility Survey documented the marginal role of cohabitation in Spain and in the rest of southern European countries by the mid‐1990s. In this research, the authors used more recent data from the 2006 Spanish Fertility, Family and Values Survey (N = 5,750) to reveal that cohabitation has spread significantly among younger cohorts and hence can no longer be considered as playing a marginal role in the family formation process.     

Creencias y expectativas respecto de la consulta médica: Un análisis de diferencias culturales

Resumen

Se compararon 102 mujeres del área metropolitana de los Angeles divididas en tres grupos según su grado de aculturación (mejico-americanas vs. anglo-americanas). Las variables consideradas se refirieron a las expectativas respecto al médico en contextos terapéuticos. Se consideraron las puntuaciones de tres medidas: La puntuación total en expectativas respecto del médico, las puntuaciones respecto a las expectativas referentes al comportamiento afectivo del médico y las puntuaciones respecto a las expectativas de tratamiento concreto. Los análisis de los resultados y el control de diversas variables tales como edad, gravedad de la enfermedad, etc., muestran la ausencia de diferencias interculturales en lo que las mujeres de la muestra esperan del médico. Si estos resultados se confirman obligarían a identificar más claramente cuándo son importantes las diferencias de aculturación y cuándo no lo son.     

Impact of Combat on the Mental Health and Well‐Being of Soldiers and Marines

This presentation introduces a summary of leading edge research and recommendations for a number of changes regarding mental health needs and services for Veterans. Those Veterans who experienced combat exposure and those who have perceived their leadership negatively have greater risks for developing subsequent PTSD. Research data provide support for the use of Battlemind Training as a useful approach to prevent mental health issues at all phases of the deployment cycle. The author also challenges the current use of DSM–IVTR diagnoses with combat Veterans.     

Modeling rare events through a pRARMAX process

7 and 8 introduce a power max-autoregressive process, in short pARMAX, as an alternative to heavy tailed ARMA when modeling rare events. In this paper, an extension of pARMAX is considered, by including a random component which makes the model more applicable to real data. We will see conditions under which this new model, here denoted as pRARMAX, has unique stationary distribution and we analyze its extremal behavior. Based on Bortot and Tawn (1998), we derive a threshold-dependent extremal index which is a functional of the coefficient of tail dependence of 14 and 15 which in turn relates with the pRARMAX parameter. In order to fit a pRARMAX model to an observed data series, we present a methodology based on minimizing the Bayes risk in classification theory and analyze this procedure through a simulation study. We illustrate with an application to financial data.     

Portions of paradise: aromatic landscapes in Chilean urban gardens (1671–1897)

ABSTRACT

The present essay identifies the smellscapes of colonial and early Republican Chile through the reconstruction of botanical aromas in private urban gardens. Using archival documents in the Chilean National Archives, the Franciscan Archives of Chile, the Judicial Archives of San Juan Province and the Historical Archives of Mendoza we identify the botanical contents of enclosed gardens and orchards in upper-class homes. In contrast to previous studies that have linked the bad odors of early modern Latin America to infirmity and poverty, our purpose is to consider the place of pleasant aromas as part of a garden typology in which the garden is a reconstruction of paradise. Through our analysis of inventories and appraisals we identify continuities in botanical contents and structure between private Chilean gardens and prototypes in Moorish Spain. Our data confirms that the aromas of roses, jasmine, and citrus were a feature of the elite Chilean garden alongside native plants, and the resulting pleasant sensorial experiences imparted a paradisiacal ideal adapted from Moorish-Spanish antecedents. Ultimately, we interpret the fragrances of such private gardens as performances of power that gave presence to the hidden sites where elite Chilean networks were forged, and thus served as ephemeral signals of social exclusivity.     

Delayed childbearing in contemporary Spain: trends and differentials

During the last decade, family formation patterns in Spain have undergone a process of substantial transformation. Younger cohorts are increasingly postponing marriage and, once they enter marriage, they tend to delay childbearing. Partly as a result of these timing shifts, period measures such as total fertility rates are likely to underestimate true fertility levels. This study focuses on the first stage of family formation: the transition to motherhood. Following a birth interval approach, the analysis depicts recent trends and differentials in the timing of first birth and explores the role of premarital pregnancies and contraceptive practice on first interval dynamics.Durant la dernière décennie en Espagne, les types de constitution de la famille ont connu de substantielles transformations. Les plus jeunes cohortes prolongent leur célibat et, une fois mariées, tendent à retarder leurs naissances. En partie comme un effet de ces changements temporels, les mesures transversales, telles que la fécondité cumulée, sous-estiment vraisemblablement les vrais niveaux de la fécondité. Cette étude concentre son attention sur la prémière étape de la formation des familles: la transition vers la maternité. En utilisant une approche longitudinale, on analyse les tendances et les différences dans le calendrier de la première naissance et l'on explore le rôle des grossesses prémaritales et des pratiques contraceptives sur la dynamique de l'intervalle entre mariage et première naissance.

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The views expressed in this article are those of the author and do not necessarily represent those of the United Nations.     

Changes in mortality and life expectancy: Some methodological issues

Measuring and explaining the effects of mortality changes on life expectancy has been discussed for the past three decades. Different approaches have been proposed using discrete or continuous methods. Two basic ideas underlie these approaches. The first compares two different mortality schedules and quantifies the contribution of each age group to the increase in life expectancy. The second analyzes how the progress in the mortality schedule translates into progress in life expectancy. This paper discusses and compares the approaches proposed by the United Nations (1982), Arriaga (1984), Pollard (1982, 1988), and Vaupel (1986), identifying their problems, advantages, and the types of situations where each one can best be applied.