A characteristic function approach to the biased sampling model,with application to robust logistic regression

Many sampling problems from multiple populations can be considered under the semiparametric framework of the biased, or weighted, sampling model. Included under this framework is logistic regression under case–control sampling. For any model, atypical observations can greatly influence the maximum likelihood estimate of the parameters. Several robust alternatives have been proposed for the special case of logistic regression. However, some current techniques can exhibit poor behavior in many common situations. In this paper a new family of procedures are constructed to estimate the parameters in the semiparametric biased sampling model. The procedures incorporate a minimum distance approach, but are instead based on characteristic functions. The estimators can also be represented as the minimizers of quadratic forms in simple residuals, thus yielding straightforward computation. For the case of logistic regression, the resulting estimators are shown to be competitive with the existing robust approaches in terms of both robustness and efficiency, while maintaining affine equivariance. The approach is developed under the case–control sampling scheme, yet is shown to be applicable under prospective sampling logistic regression as well.     

Ideology and Social Movements: The Contributions of Habermas*

Theorists of social movements have not developed a sufficiently complex perspective of the role that ideology has in the dynamics of social movements. This essay demonstrates that Habermas’theory of the autonomy of normative structures is useful to explain the independent role of ideology in determining the direction taken by social movements. Habermas’emphasis on the interrelationship between cultural traditions, consensus formation, epistemologies, and differentiated rationalization processes furnishes an alternative to the instrumentalist and ahistorical assumptions that often characterize theorists’treatment of ideology in social movements. Empirical examples from studies of social movements are utilized to demonstrate the usefulness of Habermas’approach.     

Additive and Multiplicative Models and Multistage Carcinogenesis Theory

In light of the Armitage-Doll multistage carcinogenesis theory, this paper examines the assumption that an additive relative risk relationship is indicative of two carcinogens that affect the same stage in the cancer process. We present formulas to compute excess cancer risks for a variety of patterns for limited exposure durations to two carcinogens that affect the first and penultimate stages; and using an index of synergy proposed by Thomas (1982), we find a number of these patterns to produce additive, or nearly additive, relative risk relationships. The consistent feature of these patterns is that the two exposure periods are of short duration and occur close together.     

NEGOTIATING CONTINUITY: Family and Religious Socialization for Second-Generation Asian Americans

This article examines second-generation Asian Americans' explanations of the significant influences on their own religious identities. Data include interviews (N = 73) with college-aged Asian Americans from different religious traditions and ethnic backgrounds. Respondents viewed families as the most significant influence on current religiosity. Mothers and fathers were mentioned most often, followed by extended kin, siblings, and relatives, who acted as what we call "reinforcers,""substitutes," or "contrasts" to the roles that parents played in religious socialization. These roles occurred along two religious configurations within families: heterogeneous or homogeneous degrees of religious commitment and religious affiliation. Directions for future research and contributions to the religious transmission literature follow.     

‘I’m not really sure but I hope it’s better’: early thoughts of parents and carers in a regional trial site for the Australian National Disability Insurance Scheme

The National Disability Insurance Scheme (NDIS) is one of the most significant initiatives in Australian social policy history. Its complexity has been compounded by a fast-paced introduction and ongoing refinement throughout the initial trial phase. Parents and carers of very young disabled children face particular challenges accessing and navigating NDIS systems. This article presents findings from a mixed-method pilot study examining the perspectives of parents and carers of disabled children in one NDIS trial site – the Hunter Region of New South Wales. The research highlights a number of policy assumptions potentially impacting on NDIS take up for young disabled children and their families in regional contexts. Based on research findings a number of policy suggestions and improvements for disabled children and their families entering the NDIS and other individualised funding schemes are outlined.     

Discount rates and risky sexual behaviors among teenagers and young adults

This article examines the relationship between personal discount rates and sexual behaviors in a sample of teenagers and young adults. We find that higher discount rates (an indication of less willingness to forego current consumption for future consumption) are significantly associated with a range of sexual behaviors, including ever having sex, having sex before age 16 years, and past or current pregnancy. These associations are consistent with previous studies showing a link between discounting and other, non-sexual health behaviors. JEL Classification D80 · D90 · I10     

Privatizing Social Services in the U.S.A.

Governmental and private sector social services organizations have traditionally shared important roles for provision and delivery of social services in the United States. Over the past fifty years, however, a predominant position has developed for the public sector, especially through federal funding for social service programmes. Recent challenges to the prevailing role of public sector dominance have been expressed by the proponents for privatization at a time when decreasing federal funds are made available for social service programmes. The analysis presented here examines the potential and problems associated with the privatization strategies offered through load shedding, limited-government arrangements, fee charging and competition. As a macro level approach for a comprehensive system of social service provision and delivery, these privatization strategies raise more questions than immediate solutions. A more optimistic view is taken if privatization leads to a more meaningful balance with increased co-operation between public and private social welfare auspices.     

Adolescent Religiosity and School Contexts*

Objectives. Schools serve as the primary social organizations for adolescents, structuring their lives and conveying a variety of skills, norms, and values, but relatively little is known about how schools influence the development of religious belief, attitudes, and behavior during adolescence. We explore how schools' religious norms, coupled with adolescents' pursuit of social status through conformity, affect public and private religiosity. Methods. Employing data from the National Longitudinal Study of Adolescent Health (Add Health), we use multilevel modeling to examine the impact of school context on adolescents' public and private religiosity. Results. We find that school norms are influential in shaping both public religious expressions and private devotional activities, but pursuit of social status is a motivation for change across religious contexts only of public religious activity. The effect of social status as a motivator of religious change was moderated by the strength of the adolescent's identification with the school, especially for private religiosity. Conclusions. Schools play a key role in the social development of adolescents, and students' religious beliefs and behaviors are influenced systematically and observably by the type of religious climate within the school.