3,093 research outputs found
Generalized Bayesian Record Linkage and Regression with Exact Error Propagation
Record linkage (de-duplication or entity resolution) is the process of
merging noisy databases to remove duplicate entities. While record linkage
removes duplicate entities from such databases, the downstream task is any
inferential, predictive, or post-linkage task on the linked data. One goal of
the downstream task is obtaining a larger reference data set, allowing one to
perform more accurate statistical analyses. In addition, there is inherent
record linkage uncertainty passed to the downstream task. Motivated by the
above, we propose a generalized Bayesian record linkage method and consider
multiple regression analysis as the downstream task. Records are linked via a
random partition model, which allows for a wide class to be considered. In
addition, we jointly model the record linkage and downstream task, which allows
one to account for the record linkage uncertainty exactly. Moreover, one is
able to generate a feedback propagation mechanism of the information from the
proposed Bayesian record linkage model into the downstream task. This feedback
effect is essential to eliminate potential biases that can jeopardize resulting
downstream task. We apply our methodology to multiple linear regression, and
illustrate empirically that the "feedback effect" is able to improve the
performance of record linkage.Comment: 18 pages, 5 figure
Trends in parent- and teacher-rated mental health problems among 10- and 11-year-olds in Great Britain: 1999-2012
BACKGROUND: Previous evidence indicates that mental health problems are becoming more common for adolescents. Less is known about whether these trends have continued and there has been no study to date which has specifically focused on early adolescents over a sufficiently long period. This study examines changes in parent- and teacher-reported mental health problems among 10- and 11-year-olds in 1999, 2004 and 2012 in Great Britain. METHODS: Parent and teacher ratings of the Strengths and Difficulties Questionnaire were used to compare the prevalence of conduct problems, hyperactivity/inattention, emotional problems, peer problems and total difficulties among 10- and 11-year-olds in three nationally representative British samples assessed in 1999 (n = 1904), 2004 (n = 1348) and 2012 (n = 11,397). RESULTS: Teacher reports showed improving trends for boys' and girls' mental health from 1999 to 2012, particularly for externalizing behaviours (i.e. conduct problems and hyperactivity/inattention). Parent reports, on the other hand, identified only one area of sustained improvement between 1999 and 2012, namely hyperactivity/inattention among boys. Although parent reports of girls' mental health indicate improving trends from 1999 to 2004, they also suggest worsening mental health from 2004. CONCLUSIONS: These findings suggest that perceptions of emotional and behavioural problems vary by the gender of the adolescent, the context in which they are observed or by whom they are reported
Gender-Specific Trajectories of Conduct Problems from Ages 3 to 11
Gender-specific pathways of conduct problems (CP) from toddlerhood have received little attention. Using a nationally representative sample of UK children born in 2000-2001 (6458 boys and 6340 girls), the current study (a) identified subgroups of CP pathways separately for boys and girls from ages 3 to 11 and (b) examined early precursors (pregnancy to 9Â months) of these trajectories. Group-based trajectory models identified four distinct trajectories for both boys and girls: each characterized as 'low'; 'early-onset, desisting'; 'early-onset, persistent' and 'school-onset'. This suggests that the taxonomic framework developed to conceptualise childhood-onset CP among males is also applicable to females, though needing some revision to capture heterogeneity identified during early and middle childhood. We also found significant precursors of the different trajectory groups with some variation by gender. Early socioeconomic deprivation was a significant risk factor of the early-onset pathways among both genders, but played no significant role for 'school-onset'. Childhood-onset trajectories of boys, but not girls, were predicted by parenting attitudes and behaviour
GTI-space : the space of generalized topological indices
A new extension of the generalized topological indices (GTI) approach is carried out torepresent 'simple' and 'composite' topological indices (TIs) in an unified way. Thisapproach defines a GTI-space from which both simple and composite TIs represent particular subspaces. Accordingly, simple TIs such as Wiener, Balaban, Zagreb, Harary and Randićconnectivity indices are expressed by means of the same GTI representation introduced for composite TIs such as hyper-Wiener, molecular topological index (MTI), Gutman index andreverse MTI. Using GTI-space approach we easily identify mathematical relations between some composite and simple indices, such as the relationship between hyper-Wiener and Wiener index and the relation between MTI and first Zagreb index. The relation of the GTI space with the sub-structural cluster expansion of property/activity is also analysed and some routes for the applications of this approach to QSPR/QSAR are also given
Serological evidence of cross infection in a dialysis unit hepatitis-B epidemic
Serological evidence of cross infection in a dialysis unit hepatitis-B epidemic. This study provides serological as well as epidemiological evidence that a dialysis unit hepatitis-B epidemic was spread by cross contamination. There were 74 patients and staff who developed HB-Ag-positive hepatitis during a 28-month hospital surveillance period. Twenty-six of these cases were intimately related to the dialysis unit (21 dialysis/transplant patients and five hospital staff) and 58 were not. Representative sera from each group of cases were further tested for HB-Ag subtype specificity. Thirteen of 14 dialysis/transplant patients had subtype ay whereas ten of 15 general hospital patients had the alternate phenotype ad. All four staff who had probably acquired their infection from dialysis/transplant patients were ay subtype. Eight of the dialysis/transplant patients had never received blood. Transfusion rate in the infected dialysis patients was one-third that of leukemic patients but the hepatitis rate was higher.Preuve sérologique d'une contamination croisée dans une unité de dialyse par le virus B de l'hépatite. Ce travail apporte les preuves sérologiques et épidémiologiques de la contamination croisée d'une unité d'hémodialyse par le virus B de l'hépatite. Soixante-quatorze malades et membres de l'équipe ont développé une hépatite HB-Ag positive dans les 28 mois de la surveillance de l'hôpital. Vingt-six de ces cas ont été liés étroitement à la dialyse (21 malades de dialyse ou transplantation et 5 membres de l'équipe) et 58 ne l'étaient pas. Dans chaque groupe de cas le sérum a été étudié pour identifier les phénotypes de HB-Ag. Treize des 14 malades de dialyse ou transplantation avaient le phénotype ay alors que 10 parmi 15 des malades de l'hôpital général avaient l'autre phénotype ad. Les quatre membres de l'équipe qui avaient probablement contracté leur infection à partir de malades de transplantation ou de dialyse avaient le phénotype ay. Huit des malades de dialyse ou de transplantation n'avaient jamais reçu de sang. Le débit transfusions chez les malades en dialyse atteints par l'hépatite était le tiers de celui des malades leucémiques mais l'incidence de l'hépatite a été plus grande chez les premiers
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