Finite Population Variance Estimation in Presence of Measurement Errors

In this article, we propose a class of estimators for the population variance of a quantity of interest. The estimators in the class use auxiliary information to improve efficiency, and we suppose that measurement errors are present both in the study and auxiliary variate. We take into account such problem using a regression approach. We show that the class proposed is quite flexible and general, allowing to consider many kinds of information as auxiliary one. Comparisons within estimators in the class are studied theoretically and through simulations.     

Strategies for Implementing a Tobacco-Free Campus Policy

Abstract

This report examines the rationale for creating a tobacco-free campus to utilize in passing antitobacco policies, and recommendations for overcoming barriers. As with any type of advocacy effort, a variety of impediments exist, including lack of administrative and staff support, absence of student involvement, and sparse resources. A variety of potential remedies and advocacy opportunities are explored and delineated.     

A fast exact algorithm for the problem of optimum cooperation and the structure of its solutions

Given a graph G=(V,E) with edge weights w _e ∈ℝ, the optimum cooperation problem consists in determining a partition of the graph that maximizes the sum of weights of the edges with nodes in the same class plus the number of the classes of the partition. The problem is also known in the literature as the optimum attack problem in networks. Furthermore, a relevant physics application exists.     

Sibling Facilitation Mediates the Association Between Older and Younger Sibling Alcohol Use in Late Adolescence

Previous research has shown adolescent siblings are similar in their alcohol use and that this similarity is largely due to their shared environment. Using a genetically informed sibling sample (196 full‐biological pairs, 384 genetically unrelated pairs), we confirmed that the extent to which older siblings facilitate younger siblings' alcohol use (i.e., help them get alcohol) was one factor contributing to this shared environmental association. All analyses controlled for parent and peer influences. Findings were not moderated by sibling differences in genetic relatedness, gender, or ethnicity. Proximity in sibling age strengthened these associations, somewhat. Results were especially strong for sibling pairs where the older sibling was of legal drinking age. Implications for prevention and intervention are discussed.     

Becoming a (Pan)ethnic Attorney: How Asian American and Latino Law Students Manage Dual Identities

Managing professional and personal identities often belabor upwardly mobile racialized individuals. I examine in this article how Asian American and Latino law students negotiate (pan)ethnic identities while learning to become lawyers. I contend that managing dual identities creates (pan)ethnic duty among Asian American and Latino law students. I focus on those planning to work in law firms, at least initially. While there are many career options for law students, most, irrespective of race, pursue initial careers at law firms. What leads them there? How do racialization and expectations play a role in this career aspiration? And how do students negotiate the pressure to give back, or manage the internally/externally imposed duty they feel to serve respective communities? I find that Asian American and Latino law students draw on a repertoire of strategies (marginal panethnicity, tempered altruism, and instrumental ethnicity) that encompass different accounts, identities, and roles enabling creativity and elasticity for professional and personal identities. The findings suggest that panethnicity remains salient for upwardly mobile individuals of color, even those who do not ostensibly appear to be concerned with panethnic communities and causes.     

A marginalized diffusion model for estimating age at first lower endoscopy use from current status data

Summary.  We propose an approach for estimating the age at first lower endoscopy examination from current status data that were collected via two series of cross-sectional surveys. To model the national probability of ever having a lower endoscopy examination, we incorporate birth cohort effects into a mixed influence diffusion model. We link a state-specific model to the national level diffusion model by using a marginalized modelling approach. In future research, results from our model will be used as microsimulation model inputs to estimate the contribution of endoscopy examinations to observed changes in colorectal cancer incidence and mortality.     

Assessment of Inhalation Exposures and Potential Health Risks to the General Population that Resulted from the Collapse of the World Trade Center Towers

In the days following the collapse of the World Trade Center (WTC) towers on September 11, 2001 (9/11), the U.S. Environmental Protection Agency (EPA) initiated numerous air monitoring activities to better understand the ongoing impact of emissions from that disaster. Using these data, EPA conducted an inhalation exposure and human health risk assessment to the general population. This assessment does not address exposures and potential impacts that could have occurred to rescue workers, firefighters, and other site workers, nor does it address exposures that could have occurred in the indoor environment. Contaminants evaluated include particulate matter (PM), metals, polychlorinated biphenyls, dioxins, asbestos, volatile organic compounds, particle-bound polycyclic aromatic hydrocarbons, silica, and synthetic vitreous fibers (SVFs). This evaluation yielded three principal findings. (1) Persons exposed to extremely high levels of ambient PM and its components, SVFs, and other contaminants during the collapse of the WTC towers, and for several hours afterward, were likely to be at risk for acute and potentially chronic respiratory effects. (2) Available data suggest that contaminant concentrations within and near ground zero (GZ) remained significantly elevated above background levels for a few days after 9/11. Because only limited data on these critical few days were available, exposures and potential health impacts could not be evaluated with certainty for this time period. (3) Except for inhalation exposures that may have occurred on 9/11 and a few days afterward, the ambient air concentration data suggest that persons in the general population were unlikely to suffer short-term or long-term adverse health effects caused by inhalation exposures. While this analysis by EPA evaluated the potential for health impacts based on measured air concentrations, epidemiological studies conducted by organizations other than EPA have attempted to identify actual impacts. Such studies have identified respiratory effects in worker and general populations, and developmental effects in newborns whose mothers were near GZ on 9/11 or shortly thereafter. While researchers are not able to identify specific times and even exactly which contaminants are the cause of these effects, they have nonetheless concluded that exposure to WTC contaminants (and/or maternal stress, in the case of developmental effects) resulted in these effects, and have identified the time period including 9/11 itself and the days and few weeks afterward as a period of most concern based on high concentrations of key pollutants in the air and dust.     

Male-to-Female Transgender Individuals Building Social Support and Capital From Within a Gender-Focused Network

ABSTRACT

The literature on male-to-female transgender myriad problems such individuals face in their day-to-day lives, including high rates of HIV/AIDS, addiction to drugs, violence, and lack of health care. These problems are exacerbated for ethnic and racial minority MTFs. Support available from their social networks can help MTFs alleviate these problems. This article explores how minority MTFs, specifically in an urban environment, develop supportive social networks defined by their gender and sexual identities. Using principles of community-based participatory research (CBPR), 20 African American and Latina MTFs were recruited at a community-based health care clinic. Their ages ranged from 18 to 53. Data were coded and analyzed following standard procedure for content analysis. The qualitative interviews revealed that participants formed their gender and sexual identities over time, developed gender-focused social networks based in the clinic from which they receive services, and engaged in social capital building and political action. Implications for using CBPR in research with MTFs are discussed.     

A WEIGHTED RANK MEASURE OF CORRELATION

Spearman's rank correlation coefficient is not entirely suitable for measuring the correlation between two rankings in some applications because it treats all ranks equally. In 2000, Blest proposed an alternative measure of correlation that gives more importance to higher ranks but has some drawbacks. This paper proposes a weighted rank measure of correlation that weights the distance between two ranks using a linear function of those ranks, giving more importance to higher ranks than lower ones. It analyses its distribution and provides a table of critical values to test whether a given value of the coefficient is significantly different from zero. The paper also summarizes a number of applications for which the new measure is more suitable than Spearman's.