Home About us Contact
|
Home About us Contact | ||
|
|
||
Analytic Strategies (analytic + strategy)
Selected AbstractsDisciplinary Agendas and Analytic Strategies of Research on Immigrant Transnationalism: Challenges of Interdisciplinary KnowledgeINTERNATIONAL MIGRATION REVIEW, Issue 3 2003Ewa Morawska To be successful, an interdisciplinary approach to the study of immigration and transnationalism should begin by making different disciplinary languages about this phenomenon informed by mutual understanding of the conceptual frameworks, epistemological assumptions, and explanatory strategies used in research in particular academic fields. Drawing on studies in anthropology, sociology, history, and political science, I review here these taken-for-granted assumptions about "what is knowable and how" that underlie research on immigration and transnationalism in these disciplines. In conclusion, I suggest some avenues for mutual education in different disciplinary approaches and the epistemic gains derived therefrom. [source] Multiple testing in the genomics era: Findings from Genetic Analysis Workshop 15, Group 15GENETIC EPIDEMIOLOGY, Issue S1 2007Lisa J. Martin Abstract Recent advances in molecular technologies have resulted in the ability to screen hundreds of thousands of single nucleotide polymorphisms and tens of thousands of gene expression profiles. While these data have the potential to inform investigations into disease etiologies and advance medicine, the question of how to adequately control both type I and type II error rates remains. Genetic Analysis Workshop 15 datasets provided a unique opportunity for participants to evaluate multiple testing strategies applicable to microarray and single nucleotide polymorphism data. The Genetic Analysis Workshop 15 multiple testing and false discovery rate group (Group 15) investigated three general categories for multiple testing corrections, which are summarized in this review: statistical independence, error rate adjustment, and data reduction. We show that while each approach may have certain advantages, adequate error control is largely dependent upon the question under consideration and often requires the use of multiple analytic strategies. Genet. Epidemiol. 31(Suppl. 1):S124,S131, 2007. © 2007 Wiley-Liss, Inc. [source] The value of assessing weights in multi-criteria portfolio decision analysisJOURNAL OF MULTI CRITERIA DECISION ANALYSIS, Issue 5-6 2008Jeffrey M. KeislerArticle first published online: 28 SEP 200 Abstract Analytic efforts in support of portfolio decisions can be applied with varying levels of intensity. To gain insight about how to match the effort to the situation, we simulate a portfolio of potential projects and compare portfolio performance under a range of analytic strategies. Each project is scored with respect to several attributes in a linear additive value model. Projects are ranked in order of value per unit cost and funded until the budget is exhausted. Assuming these weights and scores are correct, and the funding decisions made this way are optimal, this process is a gold standard against which to compare other decision processes. In particular, a baseline process would fund projects essentially at random, and we may estimate the value added by various decision processes above this worst case as a percentage of the increase arising from the optimal process. We consider several stylized decision rules and combinations of them: using equal weights, picking one attribute at random, assessing weights from a single randomly selected stakeholder. Simulation results are then used to identify which conditions tend to make which types of analytic strategies valuable, and to identify useful hybrid strategies. Copyright © 2009 John Wiley & Sons, Ltd. [source] Confounder summary scores when comparing the effects of multiple drug exposures,PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 1 2010Suzanne M. Cadarette PhD Abstract Purpose Little information is available comparing methods to adjust for confounding when considering multiple drug exposures. We compared three analytic strategies to control for confounding based on measured variables: conventional multivariable, exposure propensity score (EPS), and disease risk score (DRS). Methods Each method was applied to a dataset (2000,2006) recently used to examine the comparative effectiveness of four drugs. The relative effectiveness of risedronate, nasal calcitonin, and raloxifene in preventing non-vertebral fracture, were each compared to alendronate. EPSs were derived both by using multinomial logistic regression (single model EPS) and by three separate logistic regression models (separate model EPS). DRSs were derived and event rates compared using Cox proportional hazard models. DRSs derived among the entire cohort (full cohort DRS) was compared to DRSs derived only among the referent alendronate (unexposed cohort DRS). Results Less than 8% deviation from the base estimate (conventional multivariable) was observed applying single model EPS, separate model EPS or full cohort DRS. Applying the unexposed cohort DRS when background risk for fracture differed between comparison drug exposure cohorts resulted in ,7 to,+,13% deviation from our base estimate. Conclusions With sufficient numbers of exposed and outcomes, either conventional multivariable, EPS or full cohort DRS may be used to adjust for confounding to compare the effects of multiple drug exposures. However, our data also suggest that unexposed cohort DRS may be problematic when background risks differ between referent and exposed groups. Further empirical and simulation studies will help to clarify the generalizability of our findings. Copyright © 2009 John Wiley & Sons, Ltd. [source] Body size and human energy requirements: Reduced mass-specific total energy expenditure in tall adults,AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 3 2010Steven B. Heymsfield Mammalian resting energy expenditure (REE) increases as ,weight0.75 while mass-specific REE scales as ,weight,0.25. Energy needs for replacing resting losses are thus less relative to weight (W) in large compared with small mammals, a classic observation with biological implications. Human weight scales as ,height2 and tall adults thus have a greater weight than their short counterparts. However, it remains unknown if mass-specific energy requirements are less in tall adults; allometric models linking total energy expenditure (TEE) and weight with height (H) are lacking. We tested the hypothesis that mass-specific energy requirements scale inversely to height in adults by evaluating TEE (doubly labeled water) data collected by the National Academy of Sciences. Activity energy expenditure (AEE) was calculated from TEE, REE (indirect calorimetry), and estimated diet-induced energy expenditure. Main analyses focused on nonmorbidly obese subjects ,50 yrs of age with non-negative AEE values (n = 404), although results were directionally similar for all samples. Allometric models, including age as a covariate, revealed significantly (P < 0.05) greater REE, AEE, and TEE as a function of height (range H1.5,1.7) in both men and women. TEE/W scaled negatively to height (,H,0.7, P < 0.01) with predicted mass-specific TEE (kcal/kg/d) at ±2 SD for US height lower in tall compared with short men (40.3 vs. 46.5) and women (37.7 vs. 42.7). REE/W also scaled negatively to height in men (P < 0.001) and women (P < 0.01). Results were generally robust across several different analytic strategies. These observations reveal previously unforeseen associations between human stature and energy requirements that have implications for modeling efforts and provide new links to mammalian biology as a whole. Am. J. Hum. Biol. 2010. © 2009 Wiley-Liss, Inc. [source] Can the Emergency Department Algorithm Detect Changes in Access to Care?ACADEMIC EMERGENCY MEDICINE, Issue 6 2008Robert A. Lowe MD Abstract Objectives:, The "emergency department algorithm" (EDA) uses emergency department (ED) diagnoses to assign probabilities that a visit falls into each of four categories: nonemergency, primary care,treatable emergency, preventable emergency needing ED care, and nonpreventable emergency. The EDA's developers report that it can evaluate the medical safety net because patients with worse access to care will use EDs for less urgent conditions. After the Oregon Health Plan (OHP, Oregon's expanded Medicaid program) underwent cutbacks affecting access to care in 2003, the authors tested the ability of the EDA to detect changes in ED use. Methods:, All visits to 22 Oregon EDs during 2002 were compared with visits during 2004. For each payer category, mean probabilities that ED visits fell into each of the four categories were compared before versus after the OHP cutbacks. Results:, The largest change in mean probabilities after the cutbacks was 2%. Attempts to enhance the sensitivity of the EDA through other analytic strategies were unsuccessful. By contrast, ED visits by the uninsured increased from 6,682/month in 2002 to 9,058/month in 2004, and the proportion of uninsured visits leading to hospital admission increased by 51%. Conclusions:, The EDA was less useful in demonstrating changes in access to care than were other, simpler measures. Methodologic concerns with the EDA that may account for this limitation are discussed. Given the widespread adoption of the EDA among health policy researchers, the authors conclude that further refinement of the methodology is needed. [source] Using Theory to Design Effective Health Behavior InterventionsCOMMUNICATION THEORY, Issue 2 2003Martin Fishbein This article demonstrates the usefulness of two theories for the development of effective health communication campaigns. The integrative model of behavioral prediction focuses on changing beliefs about consequences, normative issues, and efficacy with respect to a particular behavior. Media priming theory focuses on strengthening the association between a belief and its outcomes, such as attitude and intention toward performing the behavior. Both the integrative model of behavioral prediction and media priming theory provide guidance with respect to the selection of beliefs to target in an intervention. The article describes the theories, shows how they can be applied to the selection of target beliefs, and, for each theory, defines the criteria for belief selection. The two theories as well as their appropriate analytic strategies are complementary rather than conflicting. [source] Early manifestations of childhood depression: influences of infant temperament and parental depressive symptomsINFANT AND CHILD DEVELOPMENT, Issue 3 2008Maria A. Gartstein Abstract In this longitudinal study, 83 parents of infants between 3 and 12 months completed questionnaires assessing demographic information, infant temperament, and maternal depression. When these children were at least 18 months of age, parents completed follow-up questionnaires assessing toddler temperament and depression-like symptoms. We were primarily interested in the contributions of infant temperament and maternal depression to toddler depressive problems, and the analytic strategy involved controlling for toddler temperament in order to isolate the influence of infancy characteristics. The findings indicated that lower levels of infant regulatory capacity and greater severity of maternal depression were predictive of toddler depression-like symptoms. Moderator effects of infant temperament were also examined, with the negative affectivity * maternal depression interaction emerging as significant. Follow-up analyses indicated that the risk for early manifestations of depression was attenuated for children with lower negative affectivity in infancy and parents who reported lower levels of their own depressive symptoms; conversely, children exhibiting higher infant negative emotionality had higher levels of depression-like symptoms as toddlers, regardless of their parents' level of depression. The present findings further suggest that parental depressive symptoms need not be ,clinically significant' to predict toddler affective problems. Copyright © 2008 John Wiley & Sons, Ltd. [source] Hierarchical Logistic Regression: Accounting for Multilevel Data in DIF DetectionJOURNAL OF EDUCATIONAL MEASUREMENT, Issue 3 2010Brian F. French The purpose of this study was to examine the performance of differential item functioning (DIF) assessment in the presence of a multilevel structure that often underlies data from large-scale testing programs. Analyses were conducted using logistic regression (LR), a popular, flexible, and effective tool for DIF detection. Data were simulated using a hierarchical framework, such as might be seen when examinees are clustered in schools, for example. Both standard and hierarchical LR (accounting for multilevel data) approaches to DIF detection were employed. Results highlight the differences in DIF detection rates when the analytic strategy matches the data structure. Specifically, when the grouping variable was within clusters, LR and HLR performed similarly in terms of Type I error control and power. However, when the grouping variable was between clusters, LR failed to maintain the nominal Type I error rate of .05. HLR was able to maintain this rate. However, power for HLR tended to be low under many conditions in the between cluster variable case. [source] Multiple Views of the Family and Adolescent Social CompetenciesJOURNAL OF RESEARCH ON ADOLESCENCE, Issue 4 2001Nancy J. Bell This research examined the linkages between congruence in perceptions of family functioning and adolescent competencies with a sample of 223 first-year college students, their mothers, and their fathers. The primary goal was to explore further the nature and importance of perceptual congruence as related to adolescent social competencies with a more informative analytic strategy than has been used in most past research (one that controls for individual perceptions of family members and takes into account direction of differences among family members), and with more comprehensive, multimethod assessments of adolescent competencies. Our congruence analyses portrayed a more complex picture of congruence and divergence than has emerged from previous studies, and highlight the importance of examining interaction patterns in future research. It is noteworthy, however, that individual perceptions of family members were more important than was congruence in relation to adolescent social competencies. The possibility that congruence effects may be more apparent when the focus is on more specific rather than global measures and on developmental as well as family interaction processes is suggested. [source] Influencing Fisheries Management: Multitasking for Maximum EffectivenessANNALS OF ANTHROPOLOGICAL PRACTICE, Issue 1 2007John R. Maiolo From the very first drafts of what later became the Magnuson-Stevens Fishery Conservation and Management Act, and the subsequent creation of regional and state counterparts, social science was supposed to play more than a perfunctory role in the nation's fishery management process. But our involvement as social scientists has not been a cakewalk and, although growing, our influence often has been limited at best. This article discusses how we can impact the process by using different styles of involvement and different research methods. Different styles of involvement include teaching, with an emphasis on recruitment of students and colleagues into the effort, along with multidisciplinary team research. This article illustrates how we must be willing to gather information on an opportunistic basis rather than be wedded to any one type of data gathering and analytic strategy as we move from one project to another. We social scientists can be most effective if we are willing to be persistent, flexible but focused, and able to employ a variety of complementary tactics. Along with this we need to find ways to participate in the management process from the inside. We must also establish our work in the fisheries management process as legitimate within our own respective professions. Finally, this article suggests that such a multifaceted strategy can be effective in other areas of policy concern. [source] Assessing the Effects of Maternal Symptoms and Homelessness on the Mental Health Problems in their ChildrenCHILD AND ADOLESCENT MENTAL HEALTH, Issue 4 2009Ilan Harpaz-Rotem Objective:, This study examines the longitudinal association between measures of child well being and maternal posttraumatic stress disorder symptoms, homelessness, substance abuse, and other psychiatric conditions. Method:, A sample of 142 mothers who were veterans of the US armed forces were assessed at program entry and every three months thereafter for one year. A repeated-measures with mixed-effects analytic strategy was used to assess the association of children's mental health, school enrolment and attendance with measures of maternal psychiatric symptoms and homelessness. Results:, Significant associations between mothers' psychiatric symptoms and child well-being were identified. However, the multivariable mixed-models suggest that increased depression and anxiety symptoms among children were associated primarily with mothers' PTSD, and not depression, symptoms. Conclusions:, These findings provide evidence of an association between maternal and child mental health and may suggest that treating maternal PTSD symptoms may also benefit children, regardless of whether the child was also exposed to the traumatic experience. [source] Dynamic Patterns of Time Use in AdolescenceCHILD DEVELOPMENT, Issue 2 2001Michael J. Shanahan Patterns of time use are tangible representations of individual identity and the meaning of age groups in the life course. How do young people allocate their time to multiple domains of involvement, including the school, workplace, family, and peer group? Drawing on longitudinal data from the Youth Development Study (N= 1,010), a person-centered analytic strategy was used to describe configurations of time use through the high school years. Over half of the students were engaged in many domains, although a substantial percentage of students focused their time on one or two domains outside the school. Students who were highly engaged in multiple domains tended to remain so across grade levels, whereas students focused on one or two domains frequently changed their commitments. Plans for school, grade point average, future orientations that emphasize marriage and good citizenship, and gender significantly predicted time-use patterns. These findings elucidate connections among school, work, and other contexts through the high school years. [source] | |||||||||||||||||||