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.     

Individual Differences in Infant Oculomotor Behavior During the Viewing of Complex Naturalistic Scenes

Little research hitherto has examined how individual differences in attention, as assessed using standard experimental paradigms, relate to individual differences in how attention is spontaneously allocated in more naturalistic contexts. Here, we analyzed the time intervals between refoveating eye movements (fixation durations) while typically developing 11‐month‐old infants viewed a 90‐min battery ranging from complex dynamic to noncomplex static materials. The same infants also completed experimental assessments of cognitive control, psychomotor reaction times (RT), processing speed (indexed via peak look during habituation), and arousal (indexed via tonic pupil size). High test–retest reliability was found for fixation duration, across testing sessions and across types of viewing material. Increased cognitive control and increased arousal were associated with reduced variability in fixation duration. For fixations to dynamic stimuli, in which a large proportion of saccades may be exogenously cued, we found that psychomotor RT measures were most predictive of mean fixation duration; for fixations to static stimuli, in contrast, in which there is less exogenous attentional capture, we found that psychomotor RT did not predict performance, but that measures of cognitive control and arousal did. The implications of these findings for understanding the development of attentional control in naturalistic settings are discussed.     

Competition and The Operational Performance of Hospitals: The Role of Hospital Objectives

We examine the effect of a hospital's objective (i.e., non‐profit vs. for‐profit) in hospital markets for elective care. Using game‐theoretic analysis and queueing models to capture the operational performance of hospitals, we compare the equilibrium behavior of three market settings in terms of such criteria as waiting times and patient costs from waiting and hospital payments. In the first setting, a monopoly, patients are served exclusively by a single non‐profit hospital; in the second, a homogeneous duopoly, patients are served by two competing non‐profit hospitals. In our third setting, a heterogeneous duopoly, the market is served by one non‐profit hospital and one for‐profit hospital. A non‐profit hospital provides free care to patients, although they may have to wait; for‐profit hospitals charge a fee to provide care with minimal waiting. A comparison between the monopolistic and each of the duopolistic settings reveals that the introduction of competition can hamper a hospital's ability to attain economies of scale and can also increase waiting times. Moreover, the presence of a for‐profit sector may be desirable only when the hospital market is sufficiently competitive. A comparison across the duopolistic settings indicates that the choice between homogeneous and heterogeneous competition depends on the patients' willingness to wait before receiving care and the reimbursement level of the non‐profit sector. When the public funder is not financially constrained, the presence of a for‐profit sector may allow the funder to lower both the financial costs of providing coverage and the total costs to patients. Finally, our analysis suggests that the public funder should exercise caution when using policy tools that support the for‐profit sector—for example, patient subsidies—because such tools may increase patient costs in the long run; it might be preferable to raise the non‐profit sector's level of reimbursement.     

A green space vision in Southeast Michigan’s most heavily industrialized area

Urban Ecosystems - In 2011, Marathon Petroleum Company LP, which has operated a refinery west of the Rouge River since 1959, initiated a voluntary property purchase program in the neighborhood...     

Rural Appalachian High School Students’ College‐Going and STEMM Perceptions

The authors examined perceptions of key social cognitive career theory (Lent, Brown, & Hackett, 1994) variables related to college‐going and science, technology, engineering, math, and medical (STEMM) careers in 10th and 11th graders (N = 892) attending 3 rural Appalachian high schools. The authors examined differences in perceptions related to gender, prospective 1st‐generation college student status, and the presence or absence of aspirations to pursue a STEMM career. Young women and young men scored similarly on all but 1 dependent variable, college‐going self‐efficacy (young women scored higher). Students who had STEMM career aspirations had higher scores on every measure than those who did not. Results suggest examining a 3rd prospective 1st‐generation college student status group—students who are unsure of their parents’ education level—as a distinct group in future research. By examining the college‐going and STEMM attitudes of rural Appalachian high school students, this study advances the literature and informs practitioners on reducing educational and vocational inequalities in this region.     

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.