Showing papers by "Florida Atlantic University published in 2010"

Bullying, cyberbullying, and suicide

Abstract: Empirical studies and some high-profile anecdotal cases have demonstrated a link between suicidal ideation and experiences with bullying victimization or offending. The current study examines the extent to which a nontraditional form of peer aggression--cyberbullying--is also related to suicidal ideation among adolescents. In 2007, a random sample of 1,963 middle-schoolers from one of the largest school districts in the United States completed a survey of Internet use and experiences. Youth who experienced traditional bullying or cyberbullying, as either an offender or a victim, had more suicidal thoughts and were more likely to attempt suicide than those who had not experienced such forms of peer aggression. Also, victimization was more strongly related to suicidal thoughts and behaviors than offending. The findings provide further evidence that adolescent peer aggression must be taken seriously both at school and at home, and suggest that a suicide prevention and intervention component is essential within comprehensive bullying response programs implemented in schools.

RUSBoost: A Hybrid Approach to Alleviating Class Imbalance

Abstract: Class imbalance is a problem that is common to many application domains. When examples of one class in a training data set vastly outnumber examples of the other class(es), traditional data mining algorithms tend to create suboptimal classification models. Several techniques have been used to alleviate the problem of class imbalance, including data sampling and boosting. In this paper, we present a new hybrid sampling/boosting algorithm, called RUSBoost, for learning from skewed training data. This algorithm provides a simpler and faster alternative to SMOTEBoost, which is another algorithm that combines boosting and data sampling. This paper evaluates the performances of RUSBoost and SMOTEBoost, as well as their individual components (random undersampling, synthetic minority oversampling technique, and AdaBoost). We conduct experiments using 15 data sets from various application domains, four base learners, and four evaluation metrics. RUSBoost and SMOTEBoost both outperform the other procedures, and RUSBoost performs comparably to (and often better than) SMOTEBoost while being a simpler and faster technique. Given these experimental results, we highly recommend RUSBoost as an attractive alternative for improving the classification performance of learners built using imbalanced data.

Cyberbullying and Self-Esteem.

Abstract: BACKGROUND: This article examines the relationship between middle school students' experience with cyberbullying and their level of self-esteem. Previous research on traditional bullying among adolescents has found a relatively consistent link between victimization and lower self-esteem, while finding an inconsistent relationship between offending and lower self-esteem. It is therefore important to extend this body of research by determining how bullying augmented through the use of technology (such as computers and cell phones) is linked to differing levels of self-esteem. METHODS: During March and April 2007, a random sample of 1963 middle school students (mean age 12.6) from 30 schools in one of the largest school districts in the United States completed a self-report survey of Internet use and cyberbullying experiences. RESULTS: This work found that students who experienced cyberbullying, both as a victim and an offender, had significantly lower self-esteem than those who had little or no experience with cyberbullying. CONCLUSIONS: A moderate and statistically significant relationship exists between low self-esteem and experiences with cyberbullying. As such, bullying prevention programs incorporated in school curricula should also include substantive instruction on cyberbullying. Moreover, educators need to intervene in cyberbullying incidents, as failure to do so may impact the ability of students to be successful at school. Language: en

The Attractive Female Body Weight and Female Body Dissatisfaction in 26 Countries Across 10 World Regions: Results of the International Body Project I

Abstract: This study reports results from the first International Body Project (IBP-I), which surveyed 7,434 individuals in 10 major world regions about body weight ideals and body dissatisfaction. Participants completed the female Contour Drawing Figure Rating Scale (CDFRS) and self-reported their exposure to Western and local media. Results indicated there were significant cross-regional differences in the ideal female figure and body dissatisfaction, but effect sizes were small across high-socioeconomic-status (SES) sites. Within cultures, heavier bodies were preferred in low-SES sites compared to high-SES sites in Malaysia and South Africa (ds = 1.94-2.49) but not in Austria. Participant age, body mass index (BMI), and Western media exposure predicted body weight ideals. BMI and Western media exposure predicted body dissatisfaction among women. Our results show that body dissatisfaction and desire for thinness is commonplace in high-SES settings across world regions, highlighting the need for international attention to this problem.

International society of sports nutrition position stand: caffeine and performance

Abstract: Position Statement: The position of The Society regarding caffeine supplementation and sport performance is summarized by the following seven points: 1.) Caffeine is effective for enhancing sport performance in trained athletes when consumed in low-to-moderate dosages (~3-6 mg/kg) and overall does not result in further enhancement in performance when consumed in higher dosages (≥ 9 mg/kg). 2.) Caffeine exerts a greater ergogenic effect when consumed in an anhydrous state as compared to coffee. 3.) It has been shown that caffeine can enhance vigilance during bouts of extended exhaustive exercise, as well as periods of sustained sleep deprivation. 4.) Caffeine is ergogenic for sustained maximal endurance exercise, and has been shown to be highly effective for time-trial performance. 5.) Caffeine supplementation is beneficial for high-intensity exercise, including team sports such as soccer and rugby, both of which are categorized by intermittent activity within a period of prolonged duration. 6.) The literature is equivocal when considering the effects of caffeine supplementation on strength-power performance, and additional research in this area is warranted. 7.) The scientific literature does not support caffeine-induced diuresis during exercise, or any harmful change in fluid balance that would negatively affect performance.

Potentially avoidable hospitalizations of nursing home residents: frequency, causes, and costs: [see editorial comments by Drs. Jean F. Wyman and William R. Hazzard, pp 760-761].

Abstract: OBJECTIVES: To examine the frequency and reasons for potentially avoidable hospitalizations of nursing home (NH) residents. DESIGN: Medical records were reviewed as a component of a project designed to develop and pilot test clinical practice tools for reducing potentially avoidable hospitalization. SETTING: NHs in Georgia. PARTICIPANTS: In 10 NHs with high and 10 with low hospitalization rates, 10 hospitalizations were randomly selected, including long- and short-stay residents. MEASUREMENTS: Ratings using a structured review by expert NH clinicians. RESULTS: Of the 200 hospitalizations, 134 (67.0%) were rated as potentially avoidable. Panel members cited lack of on-site availability of primary care clinicians, inability to obtain timely laboratory tests and intravenous fluids, problems with quality of care in assessing acute changes, and uncertain benefits of hospitalization as causes of these potentially avoidable hospitalizations. CONCLUSION: In this sample of NH residents, experienced long-term care clinicians commonly rated hospitalizations as potentially avoidable. Support for NH infrastructure, clinical practice and communication tools for health professionals, increased attention to reducing the frequency of medically futile care, and financial and other incentives for NHs and their affiliated hospitals are needed to improve care, reduce avoidable hospitalizations, and avoid unnecessary healthcare expenditures in this population. J Am Geriatr Soc 58:627–635, 2010.

A cross-country study on the effects of national culture on earnings management

Abstract: This study hypothesizes and tests whether the degree to which managers exercise earnings discretion relates to their value system (i.e., culture) as well as the institutional features (i.e., legal environment) of their country. We find that uncertainty avoidance and individualism dimensions of national culture explain managers' earnings discretion across countries, and that this association varies with the strength of investor protection. This study extends prior literature by documenting that both national culture and institutional structure are important factors that explain corporate managers' earnings discretion practices around the world, and that the influences of these factors on earnings discretion are conditional on each other.

National Adoption of International Accounting Standards: An Institutional Perspective

Abstract: Manuscript Type: Empirical Research Question/Issue: Effective corporate governance requires accurate and reliable financial information. Historically, each nation has developed and pursued its own financial standards; however, as financial markets consolidate into a global market, there is a need for a common set of financial standards. As a result, there is a movement towards harmonization of international financial reporting standards (IFRS) throughout the global economy. While there has been considerable research on the effects of IFRS adoption, there has been relatively little systematic study as to the antecedents of IFRS adoption. Consequently, this study seeks to understand why some economies have quickly embraced IFRS standards while others partially adopt IFRS and still others continue to resist. Research Findings/Results: After controlling for market capitalization and GDP growth, we find that foreign aid, import penetration, and level of education achieved within a national economy are all predictive of the degree to which IFRS standards are adopted across 132 developing, transitional and developed economies. Theoretical/Academic Implications: We found that all three forms of isomorphic pressures (i.e., coercive, mimetic, and normative) are predictive of IFRS adoption. Consequently, institutional theory with its emphasis on legitimacy-seeking by social actors was relatively well supported by our data. This suggests that the IFRS adoption process is driven more by social legitimization pressures, than it is by economic logic. Practitioner/Policy Implications: For policy makers, our findings suggest that the institutional pressures within an economy are the key drivers of IFRS adoption. Consequently, policy makers should seek to influence institutional pressures that thwart and/or enhance adoption of IFRS. For executives of multinational firms, our findings provide insights that can help to explain and predict future IFRS adoption within economies where their foreign subsidiaries operate. This ability could be useful for creating competitive advantages for foreign subsidiaries where IFRS adoption was resisted, or avoiding competitive disadvantages for foreign subsidiaries unfamiliar with IFRS standards.

High-fidelity nursing simulation: impact on student self-confidence and clinical competence.

Abstract: Development of safe nursing practice in entry-level nursing students requires special consideration from nurse educators. The paucity of data supporting high-fidelity patient simulation effectiveness in this population informed the development of a quasi-experimental, quantitative study of the relationship between simulation and student self-confidence and clinical competence. Moreover, the study reports a novel approach to measuring self-confidence and competence of entry-level nursing students. Fifty-three baccalaureate students, enrolled in either a traditional or simulation-enhanced laboratory, participated during their first clinical rotation. Student self-confidence and faculty perception of student clinical competence were measured using selected scale items of the Lasater Clinical Judgment Rubric. The results indicated an overall improvement in self-confidence and competence across the semester, however, simulation did not significantly enhance these caring attributes. The study highlights the need for further examination of teaching strategies developed to promote the transfer of self-confidence and competence from the laboratory to the clinical setting.

The intrapsychics of gender: A model of self-socialization

Abstract: This article outlines a model of the structure and the dynamics of gender cognition in childhood The model incorporates 3 hypotheses featured in different contemporary theories of childhood gender cognition and unites them under a single theoretical framework Adapted from Greenwald et al (2002), the model distinguishes three constructs: gender identity, gender stereotypes, and attribute self-perceptions The model specifies 3 causal processes among the constructs: Gender identity and stereotypes interactively influence attribute self-perceptions (stereotype emulation hypothesis); gender identity and attribute self-perceptions interactively influence gender stereotypes (stereotype construction hypothesis) ; and gender stereotypes and attribute self-perceptions interactively influence identity (identity construction hypothesis) The model resolves nagging ambiguities in terminology, organizes diverse hypotheses and empirical findings under a unifying conceptual umbrella, and stimulates many new research directions

Role of taurine in the central nervous system

Abstract: Taurine demonstrates multiple cellular functions including a central role as a neurotransmitter, as a trophic factor in CNS development, in maintaining the structural integrity of the membrane, in regulating calcium transport and homeostasis, as an osmolyte, as a neuromodulator and as a neuroprotectant. The neurotransmitter properties of taurine are illustrated by its ability to elicit neuronal hyperpolarization, the presence of specific taurine synthesizing enzyme and receptors in the CNS and the presence of a taurine transporter system. Taurine exerts its neuroprotective functions against the glutamate induced excitotoxicity by reducing the glutamate-induced increase of intracellular calcium level, by shifting the ratio of Bcl-2 and Bad ratio in favor of cell survival and by reducing the ER stress. The presence of metabotropic taurine receptors which are negatively coupled to phospholipase C (PLC) signaling pathway through inhibitory G proteins is proposed, and the evidence supporting this notion is also presented.

Sources of Group and Individual Differences in Emerging Fraction Skills.

Abstract: Results from a two year longitudinal study of 181 children from fourth through fifth grade are reported. Levels of growth in children's computation, word problem, and estimation skills using common fractions were predicted by working memory, attentive classroom behavior, conceptual knowledge about fractions, and simple arithmetic fluency. Comparisons of 55 participants identified as having mathematical difficulties to those without mathematical difficulties revealed that group differences in emerging fraction skills were consistently mediated by attentive classroom behavior and conceptual knowledge about fractions. Neither working memory nor arithmetic fluency mediated group differences in growth in fraction skills. It was also found that the development of basic fraction skills and conceptual knowledge are bidirectional in that conceptual knowledge exerted strong influences on all three types of basic fraction skills, and basic fraction skills exerted a more modest influence on subsequent conceptual knowledge. Results are discussed with reference to how the identification of potentially malleable student characteristics that contribute to the difficulties that some students have with fractions informs interventions and also will contribute to a future theoretical account concerning how domain general and domain specific factors influence the development of basic fraction skills.

Correlation-enhanced power analysis collision attack

Abstract: Side-channel based collision attacks are a mostly disregarded alternative to DPA for analyzing unprotected implementations. The advent of strong countermeasures, such as masking, has made further research in collision attacks seemingly in vain. In this work, we show that the principles of collision attacks can be adapted to efficiently break some masked hardware implementation of the AES which still have first-order leakage. The proposed attack breaks an AES implementation based on the corrected version of the masked S-box of Canright and Batina presented at ACNS 2008. The attack requires only six times the number of traces necessary for breaking a comparable unprotected implementation. At the same time, the presented attack has minimal requirements on the abilities and knowledge of an adversary. The attack requires no detailed knowledge about the design, nor does it require a profiling phase.

Florence Nightingale Endures: Legitimizing a New Professional Role Identity

Abstract: We examined the discursive processes through which a new professional role identity for registered nurses was legitimized by analysing introductory textbooks over time. We theorize five ways of rhetorically legitimizing a new professional role identity: naturalizing the past, normalizing new meanings, altering identity referents, connecting with the institutional environment, and referencing authority. In contrast to previous research focused on legitimizing new practices, we contribute to the institutional literature by showing that legitimizing a professional role identity requires the incremental development of new arguments where the past is not delegitimized. Our findings also indicate that instead of a progression from moral and pragmatic legitimacy to cognitive legitimacy, legitimizing a new role identity may focus only on moral legitimacy. Finally, our study highlights the importance of interactions between the professional task environment and the wider institutional environment as part of the process of legitimizing a professional role identity.

Rethinking Intractable Conflict: The Perspective of Dynamical Systems

Abstract: Intractable conflicts are demoralizing. Beyond destabilizing the families, communities, or international regions in which they occur, they tend to perpetuate the very conditions of misery and hate that contributed to them in the first place. Although the common factors and processes associated with intractable conflicts have been identified through research, they represent an embarrassment of riches for theory construction. Thus, the current task in this area is integrating these diverse factors into an account that provides a coherent perspective yet allows for prediction and a basis for conflict resolution in specific conflict settings. We suggest that the perspective of dynamical systems provides such an account. This article outlines the key concepts and hypotheses associated with this approach. It is organized around a set of basic questions concerning intractable conflict for which the dynamical perspective offers fresh insight and testable propositions. The questions and answers are intended to provide readers with basic concepts and principles of complexity and dynamical systems that are useful for rethinking the nature of intractable conflict and the means by which such conflict can be transformed.

Cloud Computing Fundamentals

Abstract: In the introductory chapter we define the concept of cloud computing and cloud services, and we introduce layers and types of cloud computing. We discuss the differences between cloud computing and cloud services. New technologies that enabled cloud computing are presented next. We also discuss cloud computing features, standards, and security issues. We introduce the key cloud computing platforms, their vendors, and their offerings. We discuss cloud computing challenges and the future of cloud computing.

Attribute Selection and Imbalanced Data: Problems in Software Defect Prediction

Abstract: The data mining and machine learning community is often faced with two key problems: working with imbalanced data and selecting the best features for machine learning. This paper presents a process involving a feature selection technique for selecting the important attributes and a data sampling technique for addressing class imbalance. The application domain of this study is software engineering, more specifically, software quality prediction using classification models. When using feature selection and data sampling together, different scenarios should be considered. The four possible scenarios are: (1) feature selection based on original data, and modeling (defect prediction) based on original data; (2) feature selection based on original data, and modeling based on sampled data; (3) feature selection based on sampled data, and modeling based on original data; and (4) feature selection based on sampled data, and modeling based on sampled data. The research objective is to compare the software defect prediction performances of models based on the four scenarios. The case study consists of nine software measurement data sets obtained from the PROMISE software project repository. Empirical results suggest that feature selection based on sampled data performs significantly better than feature selection based on original data, and that defect prediction models perform similarly regardless of whether the training data was formed using sampled or original data.

Evolutionary Optimization of Software Quality Modeling with Multiple Repositories

Abstract: A novel search-based approach to software quality modeling with multiple software project repositories is presented. Training a software quality model with only one software measurement and defect data set may not effectively encapsulate quality trends of the development organization. The inclusion of additional software projects during the training process can provide a cross-project perspective on software quality modeling and prediction. The genetic-programming-based approach includes three strategies for modeling with multiple software projects: Baseline Classifier, Validation Classifier, and Validation-and-Voting Classifier. The latter is shown to provide better generalization and more robust software quality models. This is based on a case study of software metrics and defect data from seven real-world systems. A second case study considers 17 different (nonevolutionary) machine learners for modeling with multiple software data sets. Both case studies use a similar majority-voting approach for predicting fault-proneness class of program modules. It is shown that the total cost of misclassification of the search-based software quality models is consistently lower than those of the non-search-based models. This study provides clear guidance to practitioners interested in exploiting their organization's software measurement data repositories for improved software quality modeling.

Infant perception of audio-visual speech synchrony.

Abstract: Three experiments investigated perception of audio-visual (A-V) speech synchrony in 4- to 10-month-old infants. Experiments 1 and 2 used a convergent-operations approach by habituating infants to an audiovisually synchronous syllable (Experiment 1) and then testing for detection of increasing degrees of A-V asynchrony (366, 500, and 666 ms) or by habituating infants to a detectably asynchronous syllable (666 ms; Experiment 2) and then testing for detection of decreasing degrees of asynchrony (500, 366, and 0 ms). Following habituation to the synchronous syllable, infants detected only the largest A-V asynchrony (0 ms vs. 666 ms), whereas following habituation to the asynchronous syllable, infants detected the largest asynchrony (666 ms vs. 0 ms) as well as a smaller one (666 ms vs. 366 ms). Experiment 3 investigated the underlying mechanism of A-V asynchrony detection and indicated that responsiveness was based on a sensitivity to stimulus-energy onsets rather than the dynamic correlation between acoustic and visible utterance attributes. These findings demonstrated that infant perception of A-V speech synchrony is subject to the effects of short-term experience and that it is driven by a low-level, domain-general mechanism.

The enigmatic Marmorkrebs (marbled crayfish) is the parthenogenetic form of Procambarus fallax (Hagen, 1870)

Abstract: A mysterious parthenogenetic cambarid crayfish (the Marmorkrebs) has been spreading across the globe for the past decade. We compare this crayfish directly to two other cambarids, Procambarus fallax and P. alleni, that have been suggested to be related or even identical to the Marmorkrebs. Using external morphology and sequences of two mitochondrial genes we show clear correspondences between Marmorkrebs and P. fallax, a species found natively throughout peninsular Florida, USA. Based on these congruent results we suggest that the Marmorkrebs is the parthenogenetic form of P. fallax. This finding has potential evolutionary and ecological implications at several levels. The Marmorkrebs might be a type of geographical parthenogenesis, but a natural population in the wild is so far unknown. Furthermore, challenges arise in regard to the respective species status of the Marmorkrebs. Taxonomically we suggest that the Marmorkrebs is treated as ‘parthenogenetic form’ of P. fallax. Last but not least, the identity of this animal and its ecology has an impact for considering potential spread and effects of this species across the globe.

The snowball effect: friendship moderates escalations in depressed affect among avoidant and excluded children.

Abstract: A three-wave longitudinal study conducted with preadolescent boys and girls (N = 231 at Time 1 [T1]) was used to assess the hypotheses that aspects of social withdrawal would be predictors of a "snowball" cascade of depressed affect, and that friendship experiences would moderate these effects. Consistent with these hypotheses, multilevel modeling showed that measures of avoidance and exclusion at T1 were associated with concurrent levels of depressed affect and were antecedent to escalating trajectories of depressed affect over time. These accelerating growth curves fit a snowball cascade model. The analyses also showed the protective effects of friendship. Specifically, the snowball effect was limited to avoidant and excluded children who were friendless. Depressed affect did not increase among avoidant and excluded children who were friended.

Active Learning From Stream Data Using Optimal Weight Classifier Ensemble

Abstract: In this paper, we propose a new research problem on active learning from data streams, where data volumes grow continuously, and labeling all data is considered expensive and impractical. The objective is to label a small portion of stream data from which a model is derived to predict future instances as accurately as possible. To tackle the technical challenges raised by the dynamic nature of the stream data, i.e., increasing data volumes and evolving decision concepts, we propose a classifier-ensemble-based active learning framework that selectively labels instances from data streams to build a classifier ensemble. We argue that a classifier ensemble's variance directly corresponds to its error rate, and reducing a classifier ensemble's variance is equivalent to improving its prediction accuracy. Because of this, one should label instances toward the minimization of the variance of the underlying classifier ensemble. Accordingly, we introduce a minimum-variance (MV) principle to guide the instance labeling process for data streams. In addition, we derive an optimal-weight calculation method to determine the weight values for the classifier ensemble. The MV principle and the optimal weighting module are combined to build an active learning framework for data streams. Experimental results on synthetic and real-world data demonstrate the performance of the proposed work in comparison with other approaches.