Showing papers by "Georgia State University published in 2009"

SVMs Modeling for Highly Imbalanced Classification

Abstract: Traditional classification algorithms can be limited in their performance on highly unbalanced data sets. A popular stream of work for countering the problem of class imbalance has been the application of a sundry of sampling strategies. In this paper, we focus on designing modifications to support vector machines (SVMs) to appropriately tackle the problem of class imbalance. We incorporate different ldquorebalancerdquo heuristics in SVM modeling, including cost-sensitive learning, and over- and undersampling. These SVM-based strategies are compared with various state-of-the-art approaches on a variety of data sets by using various metrics, including G-mean, area under the receiver operating characteristic curve, F-measure, and area under the precision/recall curve. We show that we are able to surpass or match the previously known best algorithms on each data set. In particular, of the four SVM variations considered in this paper, the novel granular SVMs-repetitive undersampling algorithm (GSVM-RU) is the best in terms of both effectiveness and efficiency. GSVM-RU is effective, as it can minimize the negative effect of information loss while maximizing the positive effect of data cleaning in the undersampling process. GSVM-RU is efficient by extracting much less support vectors and, hence, greatly speeding up SVM prediction.

Ultrafast active plasmonics

Abstract: Surface plasmon polaritons, propagating bound oscillations of electrons and light at a metal surface, have great potential as information carriers for next-generation, highly integrated nanophotonic devices [1,2]. Since the term 'active plasmonics' was coined in 2004 [3], a number of techniques for controlling the propagation of guided surface plasmon polariton signals have been demonstrated [4-7]. However, with sub-microsecond or nanosecond response times at best, these techniques are likely to be too slow for future applications in such fields as data transport and processing. Here we report that femtosecond optical frequency plasmon pulses can propagate along a metal-dielectric waveguide and that they can be modulated on the femtosecond timescale by direct ultrafast optical excitation of the metal, thereby offering unprecedented terahertz modulation bandwidth - a speed at least five orders of magnitude faster than existing technologies.

Population-based prevention of child maltreatment: the U.S. Triple p system population trial.

Abstract: The prevention of child maltreatment necessitates a public health approach. In the U.S. Triple P System Population Trial, 18 counties were randomly assigned to either dissemination of the Triple P—Positive Parenting Program system or to the services-as-usual control condition. Dissemination involved Triple P professional training for the existing workforce (over 600 service providers), as well as universal media and communication strategies. Large effect sizes were found for three independently derived population indicators: substantiated child maltreatment, child out-of-home placements, and child maltreatment injuries. This study is the first to randomize geographical areas and show preventive impact on child maltreatment at a population level using evidence-based parenting interventions.

One Hundred Questions of Importance to the Conservation of Global Biological Diversity

Abstract: We identified 100 scientific questions that, if answered, would have the greatest impact on conservation practice and policy. Representatives from 21 international organizations, regional sections and working groups of the Society for Conservation Biology, and 12 academics, from all continents except Antarctica, compiled 2291 questions of relevance to conservation of biological diversity worldwide. The questions were gathered from 761 individuals through workshops, email requests, and discussions. Voting by email to short-list questions, followed by a 2-day workshop, was used to derive the final list of 100 questions. Most of the final questions were derived through a process of modification and combination as the workshop progressed. The questions are divided into 12 sections: ecosystem functions and services, climate change, technological change, protected areas, ecosystem management and restoration, terrestrial ecosystems, marine ecosystems, freshwater ecosystems, species management, organizational systems and processes, societal context and change, and impacts of conservation interventions. We anticipate that these questions will help identify new directions for researchers and assist funders in directing funds.

Symbolic Interactionism and Family Studies

Abstract: Symbolic interactionism occupies a unique and important position in family studies. The principal theoretical orientation of the 1920s and 1930s (when family studies was endeavoring to establish itself as a science) and one of the most popular family perspectives today, symbolic interactionism probably has had more of an impact on the study of families than almost any other theoretical perspective (Hays, 1977; Howard, 1981).

Teaching Acceptance and Mindfulness to Improve the Lives of the Obese: A Preliminary Test of a Theoretical Model

Abstract: Background Obesity is a growing epidemic. Weight control interventions can achieve weight loss, but most is regained over time. Stigma and low quality of life are significant problems that are rarely targeted. Purpose A new model aimed at reducing avoidant behavior and increasing psychological flexibility, has shown to be relevant in the treatment of other chronic health problems and is worth examining for improving the lives of obese persons. Methods Patients who had completed at least 6 months of a weight loss program (N=84) were randomly assigned to receive a 1-day, mindfulness and acceptance-based workshop targeting obesity-related stigma and psychological distress or be placed on a waiting list. Results At a 3-month follow-up, workshop participants showed greater improvements in obesity-related stigma, quality of life, psychological distress, and body mass, as well as improvements in distress tolerance, and both general and weight-specific acceptance and psychological flexibility. Effects on distress, stigma, and quality of life were above and beyond the effects due to improved weight control. Mediational analyses indicated that changes in weight-specific acceptance coping and psychological flexibility mediated changes in outcomes. Conclusion Results provide preliminary support for the role of acceptance and mindfulness in improving the quality of life of obese individuals while simultaneously augmenting their weight control efforts.

Are Asians at greater mortality risks for being overweight than Caucasians? Redefining obesity for Asians.

Abstract: Objectives: To assess whether overweight Asians, assessed on the basis of WHO criteria, are at greater mortality risk than overweight Caucasians, and to determine whether alternative cut-off points (BMI 5 23?0–24?9 kg/m 2 for overweight and BMI $ 25?0 kg/m 2 for obesity) suggested by the WHO Western Pacific Regional Office are appropriate. Design: The cohort was followed prospectively until the end of 2001. All-cause and CVD mortality risks of the overweight and obese group, relative to the reference group (BMI 5 18?5–24? 9o r 18?5–22? 9k g/m 2 ), were assessed using Cox regression analysis, adjusting for age, smoking and gender. Excess deaths were estimated with a method proposed by the US Centers for Disease Control and Prevention. Setting: National Health Interview Survey (NHIS 2001) and a middle-aged perspective cohort in Taiwan. Subjects: Subjects comprised 36 386 civil servants and school teachers, aged 40 years and older, who underwent a medical examination during 1989–1992. Results: In the WHO-defined overweight group, Asians showed a significant increase in all-cause mortality risk compared with Caucasians. Asians showed risks equivalent to Caucasians’ at lower BMI (around 5 units). Every unit of BMI increase, at 25?0 kg/m 2 or above, was associated with a 9 % increase in relative mortality risk from all causes. Applying a cut-off point of 25?0 kg/m 2 for obesity would result a prevalence of 27?1 %, while the traditional WHO cut-off point of 30?0 kg/m 2 yielded obesity prevalence of 4?1 %. Excess deaths due to obesity accounted for 8?6 % of all deaths and 21?1 % of CVD deaths, based on the alternative cut-offs. Conclusions: In this Asian population, significant mortality risks started at BMI $ 25?0 kg/m 2 , rather than at BMI $ 30?0 kg/m 2 . The study supports the use of BMI $ 25?0 kg/m 2 as a new cut-off point for obesity and BMI 5 23?0–24?9 kg/m 2 for overweight. The magnitude of obesity-attributable deaths has been hitherto under-appreciated among Asians.

Role of managerial incentives and discretion in hedge fund performance

Abstract: Using a comprehensive database of hedge funds, we examine the role of managerial incentives and discretion in the performance of hedge funds. We find that hedge funds with greater managerial incentives as proxied by delta of option-like incentive fee contract, managerial ownership, and high-water mark provision are associated with superior performance. Incentive fees have no explanatory power for future returns. We also find that funds with higher degree of managerial discretion, proxied by longer lockup, notice, and redemption periods, are associated with superior performance. Our results are robust to various alternate specifications including using alternative performance measures, allowing for nonlinearity for managerial discretion, using different econometric specifications, and controlling for different data-related biases.

The Impact of Vocabulary Instruction on Passage-Level Comprehension of School-Age Children: A Meta-Analysis

Abstract: A meta-analysis of vocabulary interventions in grades pre-K to 12 was conducted with 37 studies to better understand the impact of vocabulary on comprehension. Vocabulary instruction was found to be effective at increasing students' ability to comprehend text with custom measures (d = 0.50), but was less effective for standardized measures (d = 0.10). When considering only custom measures, and controlling for method variables, students with reading difficulties (d = 1.23) benefited more than three times as much as students without reading problems (d = 0.39) on comprehension measures. Gains on vocabulary measures, however, were comparable across reading ability. In addition, the correlation of vocabulary and comprehension effects from studies reporting both outcomes was modest (r = .43).

Counterfactual Thinking and Impact Evaluation in Environmental Policy

Abstract: Impact evaluations assess the degree to which changes in outcomes can be attributed to an intervention rather than to other factors. Such attribution requires knowing what outcomes would have looked like in the absence of the intervention. This counterfactual world can be inferred only indirectly through evaluation designs that control for confounding factors. Some have argued that environmental policy is different from other social policy fields, and thus attempting to establish causality through identification of counterfactual outcomes is quixotic. This chapter argues that elucidating causal relationships through counterfactual thinking and experimental or quasi-experimental designs is absolutely critical in environmental policy, and that many opportunities for doing so exist. Without more widespread application of such approaches, little progress will be made on building the evidence base in environmental policy. © Wiley Periodicals, Inc.

The High Angular Resolution Multiplicity of Massive Stars

Abstract: : We present the results of a speckle interferometric survey of Galactic massive stars that complements and expands upon a similar survey made over a decade ago The speckle observations were made with the Kitt Peak National Observatory and Cerro Tololo Inter-American Observatory 4 m telescopes and USNO speckle camera, and they are sensitive to the detection of binaries in the angular separation regime between 0"03 and 5" with relatively bright companions (deltaV < 3) We report on the discovery of companions to 14 OB stars In total we resolved companions of 41 of 385 O-stars (11%), 4 of 37 Wolf-Rayet stars (11%), and 89 of 139 B-stars (64%; an enriched visual binary sample that we selected for future orbital determinations) We made a statistical analysis of the binary frequency among the subsample that are listed in the Galactic O Star Catalog by compiling published data on other visual companions detected through adaptive optics studies and/or noted in the Washington Double Star Catalog and by collecting published information on radial velocities and spectroscopic binaries We find that the binary frequency is much higher among O-stars in clusters and associations compared to the numbers for field and runaway O-stars, consistent with predictions for the ejection processes for runaway stars We present a first orbit for the O-star delta Orionis; a linear solution of the close, apparently optical, companion of the O-star iota Orionis; and an improved orbit of the Be star delta Scorpii Finally, we list astrometric data for another 249 resolved and 221 unresolved targets that are lower mass stars that we observed for various other science programs

Walking Away from Terrorism: Accounts of Disengagement from Radical and Extremist Movements

Abstract: Foreword Preface: A Personal Reflection on Fieldwork 1. Qualities Are Not Causes 2. How, When and Why Terrorism Ends 3. "Prison was a good thing" 4. "I volunteered" 5. "There is no conscious decision" 6. "A step too far" 7. "They were once my people" 8. "I don't believe in integration" 9. Conclusions Bibliography

Corporate Social Responsibility: An Empirical Investigation of U.S. Organizations

Abstract: Organizations that believe they should “give something back” to the society have embraced the concept of corporate social responsibility (CSR) Although the theoretical underpinnings of CSR have been frequently debated, empirical studies often involve only limited aspects, implying that theory may not be congruent with actual practices and may impede understanding and further development of CSR The authors investigate actual CSR practices related to five different stakeholder groups, develop an instrument to measure those CSR practices, and apply it to a survey of 401 US organizations Four different clusters of organizations emerge, depending on the CSR practice focus The distinctive features of each cluster relate to organizational demographics, perceived influence of stakeholders, managers’ perceptions of the influence of CSR on performance, and organizational performance

Tax morale affects tax compliance: Evidence from surveys and an artefactual field experiment

Abstract: Our working hypothesis is that cross-cultural differences in tax compliance behavior have foundations in the institutions of tax administration and citizen assessment of the quality of governance. Tax compliance being a complex behavioral issue, its investigation requires use of a variety of methods and data sources. Results from artefactual field experiments conducted in countries with substantially different political histories and records of governance quality demonstrate that observed differences in tax compliance levels persist over alternative levels of enforcement. The experimental results are shown to be robust by replicating them for the same countries using survey response measures of tax compliance.

Managerial Incentives and Corporate Fraud: The Sources of Incentives Matter

Abstract: Operating performance and stock return results imply that managers who commit fraud anticipate large stock price declines if they were to report truthfully, which would cause greater losses for managerial stockholdings than for options because of differences in convexity. Fraud firms have significantly greater incentives from unrestricted stockholdings than control firms do, and unrestricted stockholdings are their largest incentive source. Our results emphasize the importance of the shape and vesting status of incentive payoffs in providing incentives to commit fraud. Fraud firms also have characteristics that suggest a lower likelihood of fraud detection, which implies lower expected costs of fraud. Copyright 2009, Oxford University Press.

Corporate social responsibility: an empirical investigation of U.S. organizations

Abstract: Organizations that believe they should “give something back” to the society have embraced the concept of corporate social responsibility (CSR). Although the theoretical underpinnings of CSR have been frequently debated, empirical studies often involve only limited aspects, implying that theory may not be congruent with actual practices and may impede understanding and further development of CSR. The authors investigate actual CSR practices related to five different stakeholder groups, develop an instrument to measure those CSR practices, and apply it to a survey of 401 U.S. organizations. Four different clusters of organizations emerge, depending on the CSR practice focus. The distinctive features of each cluster relate to organizational demographics, perceived influence of stakeholders, managers’ perceptions of the influence of CSR on performance, and organizational performance.

Joint Engagement and the Emergence of Language in Children with Autism and Down Syndrome

Abstract: Systematic longitudinal observations were made as typically developing toddlers and young children with autism and with Down syndrome interacted with their caregivers in order to document how joint engagement developed over a year-long period and how variations in joint engagement experiences predicted language outcome. Children with autism displayed a persistent deficit in coordinated joint attention; children with Down syndrome were significantly less able to infuse symbols into joint engagement. For all groups, variations in amount of symbol-infused supported joint engagement, a state in which the child attended to a shared object and to language but not actively to the partner, contributed to differences in expressive and receptive language outcome, over and above initial language capacity.

Cartography: maps 2.0

Abstract: At 11.35 am PDT on 18 September 2007 at Vandenberg Air Force base in California, DigitalGlobe’s new WorldView-1 satellite launched into orbit. The satellite is capable of collecting imagery over as much as three-quarters of a million square kilometers a day in resolution as fi ne as 0.5 m. A second satellite will be launched in 2008, capable of photographing nearly a million square kilometers daily at the same high resolution. The data are twice the resolution of the pre-vious industry leader, the IKONOS satellite launched in 1999 and close to the military’s own resolution of 10 cm (Monmonier, 2002).What is significant about the launch is not only the extent and resolution of the imagery (which from all vendors now covers over half of the world’s population) but also the fact that this imagery will be available commercially (look for it in Google Earth). Such imagery, alongside the tremendous possibilities of ‘crowdsourced’ geospatial data, represent interesting new develop-ments in cartography.In the fi rst of three reviews assessing the current state of cartography, I focus on the explosion of new ‘spatial media’ on the web. This topic goes under a bewildering number of names including the geospatial web or geoweb (Scharl and Tochtermann, 2007), neogeography (Turner, 2006), locative media (Rheingold, 2002), DigiPlace (Zook and Graham, 2007a), spatial crowdsourcing or geocollaboration (Hopfer and MacEachren, 2007) and map hacking (Erle

Racializing the Glass Escalator: Reconsidering Men's Experiences with Women's Work

Abstract: Many men who work in women's professions experience a glass escalator effect that facilitates their advancement and upward mobility within these fields. Research finds that subtle aspects of the interactions, norms, and expectations in women's professions push men upward and outward into the higher-status, higher-paying, more “masculine” positions within these fields. Although most research includes minority men, little has explicitly considered how racial dynamics color these men's encounters with the mechanisms of the glass escalator. In this article, the author examines how intersections of race and gender combine to shape experiences for minority men in the culturally feminized field of nursing and finds that the upward mobility implied by the glass escalator is not uniformly available to all men who do “women's work.” The author concludes that the glass escalator is a racialized concept and a gendered one and considers the implications of this for future studies of men in feminized occupations.

Leaving Terrorism Behind: Individual and Collective Disengagement

Abstract: Foreword (TBC) 1. Introduction Tore Bjorgo and John Horgan Part 1: Processes 2. Individual disengagement: A psychological analysis John Horgan 3. Processes of disengagement from violent groups of the extreme right Tore Bjorgo 4. How terrorist campaigns end Audrey Kurth Cronin 5. Leaving left-wing terrorism in Italy: A sociological analysis Donatella della Porta 6. Leaving terrorism behind in Northern Ireland and the Basque Country: reassessing anti terrorist policies and the "peace processes" Rogelio Alonso 7. The renunciation of violence by Egyptian jihadi organisations Diaa Rashwan Part 2: Programmes 8. Exit from right-wing extremist groups: Lessons from disengagement programmes in Norway, Sweden and Germany Tore Bjorgo, Sara Grunenberg and Jaap van Donselaar 9. Disengagement and Beyond: A case study of demobilization in Colombia Marcella Ribetti 10. De-radicalisation and rehabilitation programmes targeting militant jihadists: An overview Richard Barrett and Laila Bokhari 11. Opening up the Jihadi debate: Yemen's Committee for Dialogue Christopher Boucek, Shazadi Beg, and John Horgan 12. The rehabilitation of Jemaah Islamiyah detainees in Southeast Asia: A preliminary assessment Zachary Abuza 13. Extremist reeducation and rehabilitation in Saudi Arabia Christopher Boucek 14. Pakistan: In search of a disengagement strategy Shazadi Beg and Laila Bokhari Part 3: Conclusions 15. Conclusions Tore Bjorgo and John Horgan

Urban Middle School Students' Perceptions of Bullying, Cyberbullying, and School Safety

Abstract: This study examined 427 urban middle school students' perceptions of bullying, cyberbullying, and school safety utilizing the Student Survey of Bullying Behavior-Revised 2 (Varjas, Meyers, & Hunt, 2006). A unique finding is that cyberbullying may represent a unique modality of victimization and bullying compared with other school-based modalities. Cyberbullying and relational bullying were not associated with perceived school safety. Males reported more physical victimization, verbal victimization, and verbal bullying, and less relational victimization. Males and older students reported feeling safer at school. Older students reported less physical, verbal, and relational victimization, and less physical and verbal bullying. Importantly, physical, verbal, and relational bullying and victimization may represent more general underlying constructs of bullying and victimization, calling into question the distinctiveness of individual forms.

Carbohydrate recognition by boronolectins, small molecules, and lectins

Abstract: Carbohydrates are known to mediate a large number of biological and pathological events. Small and macromolecules capable of carbohydrate recognition have great potentials as research tools, diagnostics, vectors for targeted delivery of therapeutic and imaging agents, and therapeutic agents. However, this potential is far from being realized. One key issue is the difficulty in the development of "binders" capable of specific recognition of carbohydrates of biological relevance. This review discusses systematically the general approaches that are available in developing carbohydrate sensors and "binders/receptors," and their applications. The focus is on discoveries during the last 5 years.

Are Product Returns a Necessary Evil? Antecedents and Consequences

Abstract: The firm–customer exchange process consists of three key parts: (1) firm-initiated marketing communications, (2) customer buying behavior, and (3) customer product return behavior.To date, the literature in marketing has largely focused on how marketing communications affect customer buying behavior and, to some extent, how past buying behavior affects a firm's decisions to initiate future marketing communications. However, the literature on product returns is sparse, especially in relation to analyzing individual customer product return behavior. Although the magnitude of the value of product returns is known to be high ($100 billion per year), how it affects customer buying behavior is not known because of a lack of data availability and understanding of the role of product returns in the firm–customer exchange process. Given that product returns are considered a hassle for a firm's supply chain management and a drain on overall profitability, it is important to study product return behavior. T...