Estimating sexual behavior parameters from routine sexual behavior data

In mathematical models for predicting the spread of sexually transmitted diseases (STDs), the rate of acquisition of new sex partners and concurrency, the number of simultaneous sexual partnerships, are important parameters. Yet, information on these parameters is rarely obtained in routine sexual behavior surveys; instead, questions about the total number of sex partners during specific periods are often asked. We present two methods that estimate the rate of partnership acquisition and concurrency from reported numbers of sex partners in two overlapping periods. The first method assumes homogeneous behavior, while the second method also takes account of heterogeneity in sexual behavior. Both methods assume random (Poisson) partnership acquisition and the possibility of overlap in relationships. For both methods it might be relevant to distinguish individuals who are in a stable relationship from those who are not.     

Religion and Subjective Well-Being in Ghana

Using 2008 Afrobarometer survey data, we examine the relationship between religion and subjective well-being (SWB) in Ghana, as well as religious group differences in their experiences of SWB. Two measures of religion—religious affiliation and religious importance, and two measures of SWB—absolute SWB (own perceived living conditions) and relative SWB (own living conditions compared to those of other Ghanaians) are employed in this study. Results show that religious affiliation is significantly related to both measures of SWB although associations depicted for such relationships were not strong. Religious importance significantly related to relative SWB only (with a weak-to-moderate association). Significant religious affiliation and religious importance group differences are found on both SWB outcomes via non-parametric test procedures (Kruskal–Wallis H test, followed by post hoc tests). On balance, the None/Traditional religious group experienced less favorable SWB than Other Christian, Evangelical/Pentecostal, and Muslim groups, especially for absolute SWB, while the None/Traditional group experienced particularly less favorable relative SWB than the Protestant group. Religious importance groups also significantly differed in such a way that the group that considered religion very important had more favorable experiences of both types of SWB than the group that considered religion not at all/not very important. Other significant differences on both outcomes are found among ethnic, educational, and regional groups. In view of the findings, the study contributes to SWB research and suggests policy implications.     

An Exploratory Study of Religion and Trust in Ghana

Based on individual-level data from 2008 Afro-barometer survey, this study explores the relationship between religion (religious affiliation and religious importance) and trust (interpersonal and institutional) among Ghanaians. Employing hierarchical multiple regression technique, our analyses reveal a positive relationship between religious affiliation and both measures of trust among Ghanaians. A positive relationship between Catholic, Protestant, Muslim, Pentecostal/Evangelical faiths and interpersonal trust compared to non/traditional religion are detected. The data also reveal that upon controls, only Catholic and Pentecostal/Evangelical show significant positive effect on institutional trust among Ghanaians compared to non/traditional religion. It is worth noting that religious importance does not significantly predictor of neither interpersonal nor institutional trust among Ghanaians. The overall effect of religion on trust is weak, and weaker for institutional trust. Most of the difference relates to the difference between world religions and traditional religions. Place of residence, political affiliation, region of residence, ethnicity, and education are significant nonreligious predictors of both institution and interpersonal trust among Ghanaians. The findings further show that whereas age significantly influences only interpersonal trust, gender, life satisfaction, media exposure, sense of corruption, and sense of unfair treatment are significant factors molding institutional trust among Ghanaians. Policy implications of the study are discussed, emphasizing the need to incorporate religious organizations in efforts aimed at boosting interpersonal and institutional trust among Ghanaians. Religious-specific trust promotion program is suggested as possible strategy likely to succeed in Ghana. The need for more detailed studies in this important but ignored area is emphasized.     

Parameter estimation in a highly non-linear model using simultaneous perturbation stochastic approximation

Often it is necessary to estimate the parameters of a model or unknown system. Various techniques exist to accomplish this task, including Kalman and Wiener filtering, least-mean-square (LMS) algorithms, and the Levenberg-Marquardt(L-M) algorithm. These techniques require an analytic form of the gradient of the function of the parameters to be estimated. A key feature of the simultaneous perturbation stochastic approximation (SPSA) method is that it is a gradient-free optimization technique (Spall; 1992,1998a,b, 1999). In the current problem, the function of parameters to be identified is highly non-linear and of sufficient difficulty that obtaining an analytic form of the gradient is impractical. Therefore, in this paper the

performance of the SPSA algorithm will be examined in terms of parameter selection, data requirements, and convergence performance on this non-linear problem. Results will be reported on both a first-order "standard" implementation of SPSA and on a second-order version of SPSA that tends to enhance convergence.     

Single use conservative confidence regions in multivariate controlled calibration

We consider a multivariate linear model for multivariate controlled calibration, and construct some conservative confidence regions, which are nonempty and invariant under nonsingular transformations. The computation of our confidence region is easier compared to some of the existing procedures. We illustrate the results using two examples. The simulation results show the closeness of the coverage probability of our confidence regions to the assumed confidence level.     

ENGAGING COMMUNITY IN A CYCLE OF PRAXIS

This study employed an action research model known as the community wellness cycle of praxis in research with culturally diverse community members from the St Albans region (Melbourne, Australia). The major aim of the study was to gain a theoretical and pragmatic understanding of well-being from a multicultural perspective. In order to meet this aim, a qualitative study was designed to find out (1) What are the community ideals; needs; and strengths of residents of St Albans, and (2) What actions can be undertaken to improve the well-being of the community? The research involved focus groups with a total of 29 Anglo, Maltese, Vietnamese and Italian community members. The first research question was addressed by asking community members systematically about positive and negative aspects of personal, relational and collective well-being. The second research question was addressed by asking community members to generate ideas on what could be done to improve well-being and by identifying issues of concern that emerged throughout the research. The issues identified by participants offer a rich picture of community ideals, strengths and needs, as well as possible actions that could improve personal, relational and collective wellness in St Albans.

Cette étude utilise un approche de recherche action connu sous le nom du cycle de bien-être de praxis de recherche avec des membres culturellement varies dans un banlieue de Melbourne (Australie). Le but principal de l’étude était de comprendre théoriquement et pragmatiquement bien-être dans d'une perspective multiculturelle. Dans ce perspective étude qualitative a été conçue pour identifier (1) ce que sont les opinions des groupes diverses; leurs besoins et leurs atouts, et (2) de quelles actions peuvent être entreprises affin d améliorer le bien-être de ces groupes? La recherche a utilisé 29 Anglo-Australiens, Maltais, Vietnamiens et Italiens. Les premières questions ce sont posées a propos des aspects positifs et négatifs de bien-être individuel et collectif. Ensuite des questions ont été demandé à propos des idées sur ce qui on pourrait être fait pour améliorer le bien-être et en identifiant leurs soucis. Les soucis identifiées par les participants offrent une image riche des images et des représentations leurs atouts leurs, aussi bien que les actions qui pourraient améliorer le bien-être individuel et collective.     

COMMUNICATION and FREE-RIDING BEHAVIOR: THE VOLUNTARY CONTRIBUTION MECHANISM

We examine experimentally the role of active communication as a mechanism for improving economic efficiency in a voluntary contribution public goods environment. With no communication this environment has been shown to induce significant subop-timality, approaching zero contributions with iteration of the decision environment. Communication is shown to improve group optimality significantly. We examine the robustness of our results in increasingly complex environments and in environments in which there has been a history of communication but active communication is no longer available.     

Infant Mortality by Cause of Death: Main and Interaction Effects

We examine infant mortality among the 1980-1982 live birth cohorts in the state of Florida, specific to five categories of underlying cause of death: infections, perinatal conditions, delivery complications, congenital malformations, and sudden infant death syndrome. The gross and net effects of eight categorical and continuous independent variables, along with 11 first-order interactions, are examined with microlevel data through the use of multinomial logit regression. Findings suggest the complexity of variable effects by cause of death and indicate the simultaneous importance of biological and social factors. It is important that the pattern of interactions suggests an overall dependence of infant life chances on social circumstances. It also suggests that these effects are attenuated for some variables and causes of death at lower birth weights, probably due to advances in health care organization, access, and technology.