Maximum Likelihood Inference for Log-linear Models Subject to Constraints of Double Monotone Dependence

To model an hypothesis of double monotone dependence between two ordinal categorical variables A and B usually a set of symmetric odds ratios defined on the joint probability function is subject to linear inequality constraints. Conversely in this paper two sets of asymmetric odds ratios defined, respectively, on the conditional distributions of A given B and on the conditional distributions of B given A are subject to linear inequality constraints. If the joint probabilities are parameterized by a saturated log-linear model, these constraints are nonlinear inequality constraints on the log-linear parameters. The problem here considered is a non-standard one both for the presence of nonlinear inequality constraints and for the fact that the number of these constraints is greater than the number of the parameters of the saturated log-linear model.This work has been supported by the COFIN 2002 project, references 2002133957_002, 2002133957_004. Preliminary findings have been presented at SIS (Società Italiana di Statistica) Annual Meeting, Bari, 2004.     

Exploring the Hierarchical Structure of Pacific Identity and Wellbeing

To understand outcomes for Pacific peoples in New Zealand we need to further our psychological knowledge of the relationship between Pacific identity and wellbeing. We map the hierarchical organization of Pacific identity and wellbeing using a novel top-down factor analytic approach applied to the Pacific Identity and Wellbeing Scale (PIWBS; N = 586). Analyses indicated that Pacific identity experiences were organized within two broad dimensions reflecting Identity Engagement and Cultural Wellbeing. Critically, our analysis showed that Religious Centrality and Embeddedness emerged jointly from these dual broad domains. Religious identification provides a bridging link between identity and wellbeing for Pacific peoples. Identifying the relationships of Pacific identity and wellbeing factors, and how religious identification emerges jointly from these two broad domains, provides valuable information in how the Pacific self may be cognitively organized and may assist in future research directions in this area. We assert that this general statistical model provides broad conceptual insights into how Pacific peoples experience their identity and culture, and how this relates to various social indicators of health and wellbeing at a broad, theoretical level. In particular, we offer a conceptual analysis of possible insights from our hierarchical model of identity and wellbeing for understanding Pacific suicide in New Zealand.     

Remittance behaviours of foreigners in Italy

This article investigates the determinants of remittance behaviours among foreigners in Italy and intends to gain a better understanding of the temporal pattern of remittances. The analysis is based on data from the 2009 “Italian Statistics on Income and Living Conditions of Households with Foreigners”. The decisions on whether to remit and how much to remit are separately yet simultaneously estimated using a zero‐inflated beta regression model. The findings reveal that remittances are driven by a mix of altruistic and self‐interest motives that may persist for many years. Many covariates included in the model have a different effect on the propensity to remit and on the relative amount of remittances. We find some evidence that the average propensity to remit follows an M‐shaped trajectory over time. However, the model specification including only time and time squared proves that the inverted‐U shape trajectory, well‐established in the literature, still remains a better choice in terms of parsimoniousness and flexibility. Among those who remit, time since migration does not have any significant effect on the normalized amount remitted.     

Modelling two way contingency tables with recursive logits and odds ratios

In this work a new type of logits and odds ratios, which includes as special cases the continuation and the reverse-continuation logits and odds ratios, are defined. We prove that these logits and odds ratios define a parameterization of the joint probabilities of a two way contingency table. The problem of testing equality and inequality constraints on these logits and odds ratios is examined with particular regard to two new hypotheses of monotone dependence. Work partially supported by a MIUR2004 grant. Preliminary findings have been presented at SIS (Società Italiana di Statistica) Annual Meeting, Torino, 2006.     

Generalized Jackknife-Based Estimators for Univariate Extreme-Value Modeling

In this article, we revisit the importance of the generalized jackknife in the construction of reliable semi-parametric estimates of some parameters of extreme or even rare events. The generalized jackknife statistic is applied to a minimum-variance reduced-bias estimator of a positive extreme value index—a primary parameter in statistics of extremes. A couple of refinements are proposed and a simulation study shows that these are able to achieve a lower mean square error. A real data illustration is also provided.     

Neonate and Infant Emotion Expression Perceived by Adults

This exploratory study investigates the meaning that adults attribute to the facial expressions of neonates and young infants using different types of scales, and tries to assess whether adult judgments get more precise as the infants get older. We videotaped longitudinally six infants' facial expressions in 5 everyday life situations at 3 days, 1 month, and 3 months old. Untrained adult decoders had to assess the activation and pleasure/displeasure levels signaled by the isolated videotaped facial expressions, recognize the stimulus situations, and attribute a verbal label to each expression. Our results showed that inter-decoder agreement was higher when the babies' facial expressions were considered as signals of activation or of pleasure/displeasure, and decreased significantly when the expressions had to be interpreted as signals of specific situations or when a verbal label had to be ascribed. The specificity and the accuracy of the answers, and inter-decoder agreement, were higher for the older infants.     

The family culture of negotiation—a result of changing parent‐child relationships

Case studies of parent‐child relations in three different European regions—West Germany, East Germany and the Netherlands—offer material for the comparative analysis of the ongoing intra‐familial process of modernization and civilization in post‐war West European societies. The data are drawn from extended narrative interviews with twelve‐year‐olds and from parallel but separate semi‐structured ‘mirrored’ interviews with the same children and their parents. The results of the analysis show that family relations in general, and parent‐child relations in particular, are increasingly marked by a familial ‘culture of negotiation’. This suggests that the balance of intergenerational power relations is currently in the process of change. To a greater or lesser extent, contemporary family relations are characterized by situationally grounded processes of negotiation between parents and children.     

Perceived leader integrity: Supporting the construct validity and utility of a multi-dimensional measure in two samples

The empirical study of perceived leader integrity has lagged its intuitively appealing role as a fundamental characteristic of effective leaders. Following theoretical examinations of the definition of integrity and previous work arguing that perceived integrity emerges from judgments of leader consistency and leader morality, we developed a multidimensional measure that includes both perceived morality and consistency items. In a first sample of university students, confirmatory factor analyses and results from regression analyses relating the dimensions to direct measures of leader integrity and trust offer partial support for the utility of including dimensions of moral behavior and consistency (represented by behavioral integrity). Further, we replicated these findings in a second sample of working professionals and found support for our hypotheses showing that dimensions assessing behavioral integrity and moral behavior related to leader effectiveness, job satisfaction, work engagement, and intent to quit as mediated by trust in the leader.