• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 36
  • 11
  • 2
  • 1
  • 1
  • 1
  • Tagged with
  • 57
  • 57
  • 44
  • 17
  • 16
  • 12
  • 11
  • 11
  • 11
  • 10
  • 10
  • 7
  • 6
  • 6
  • 6
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Permutation based microarray gene selection methods with covarience adjustment applicable to complex diseases /

Wagner, Brandie D. January 2007 (has links)
Thesis (Ph.D. in Analytic Health Sciences) -- University of Colorado Denver, 2007. / Typescript. Includes bibliographical references (leaves 57-60). Free to UCD affiliates. Online version available via ProQuest Digital Dissertations;
22

A statistical approach identifying and limiting the effect of influential observations in linear regression

Jones, Tamekia L. January 2008 (has links) (PDF)
Thesis (Ph.D.)--University of Alabama at Birmingham, 2008. / Title from first page of PDF file (viewed on June 25, 2009). Includes bibliographical references.
23

A simulation analysis modeling dependence in closed population capture-recapture studies

Wild, Robert Clinton. January 2008 (has links) (PDF)
Thesis--University of Oklahoma. / Bibliography: leaves 79-81.
24

A comparison of stratified and unstratified modeling for binary logistic regression in the presence of a simulated interaction

Beebe, Claire Elizabeth. January 2008 (has links) (PDF)
Thesis--University of Oklahoma. / Bibliography: leaves 48-49.
25

New methods for variable selection with applications to survival analysis and statistical redundancy analysis using gene expression data /

Hu, Simin. January 2007 (has links)
Thesis (Ph. D.)--Case Western Reserve University, 2006. / [School of Medicine] Department of Epidemiology and Biostatistics. Includes bibliographical references. Available online via OhioLINK's ETD Center.
26

Differential gene expression between patients with acute lymphocytic leukemia and patients with acute myeloid leukemia : the use of analysis of variance models in microarray data analysis /

Istook, Diana Lee. January 2004 (has links) (PDF)
Thesis--University of Oklahoma. / Bibliography: leaves 90-93.
27

Some methods for the analysis of skewed data /

Dinh, Phillip V. January 2006 (has links)
Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 99-105).
28

Investigating How Undergraduate Students Develop Scientific Reasoning Skills When Coordinating Data and Model Representations in Biology

Zagallo, Patricia, Zagallo, Patricia January 2017 (has links)
There has been a call to reform science education to integrate scientific thinking practices, such as data interpretation and modeling, with learning content in science classrooms. This call to reform has taken place in both K-12 science education through Next Generation Science Standards and undergraduate education through AAAS initiative Vision and Change in Undergraduate Biology Education. This dissertation work examines undergraduate students' learning of multiple scientific thinking skills in a curricular format called Teaching Real data Interpretation with Models (TRIM) applied to a large-enrollment course in Cellular and Developmental Biology. In TRIM, students are provided worksheets in groups and tasked to interpret authentic biological data. Importantly, groups are tasked to relate their data interpretations to a 2D visual model representation of the relevant biological process. This dissertation work consists of two studies with the overarching question: How do students use model representations to interpret data interpretations? In the first study, we primarily describe how students learn to navigate and interpret discipline-based data representations. We found the majority of groups could construct quality written data interpretations. Qualitative coding analysis on group discourse found students relied on strategies such as decoding the data representation and noticing data patterns together to construct claims. Claims were refined through spontaneous collaborative argumentation. We also found groups used the provided model to connect their data inferences to a biological context. In the second study, we primarily target our analysis on how individual students relate their data interpretations to different modeling tasks, including student-generation of their own model drawing. I interviewed students one-on-one as they worked through TRIM-style worksheets. From iterative qualitative analysis of transcripts and collected video on hand movements, I characterize the forms of reasoning at play at the interface of data and model representations. I propose a model at the end of Study 2 describing three modes of reasoning in data abstraction into models. I found when relating between data and models, students needed to link signs in both representations to a common referent in the real-world phenomenon. Establishing this sign-referent relationship seemed to depend on bringing in outside mechanistic information about the phenomenon. Once a mechanism was established, students could fluidly move between data and model representations through mechanistic reasoning. Thus data abstraction seems to rely on mechanistic reasoning with models. The findings from this dissertation work support the feasibility of student development of multiple scientific thinking skills within a large lecture course, and provide targets for curriculum and assignment designs centered on teaching higher order reasoning skills.
29

How much compliance is enough? Examining the effect of different definitions of compliance on estimates of treatment efficacy in randomized controlled trials.

Grey, Scott F. 16 August 2013 (has links)
No description available.
30

Análise multinível da cobertura vacinal no Município de São Paulo / Multilevel analysis of immunization coverage in São Paulo City

Ribeiro, Manoel Carlos Sampaio de Almeida 10 August 2005 (has links)
Vigilância Epidemiológica, é a forma através do qual o SUS busca produzir impacto em termos de controle, eliminação e até erradicação de um conjunto definido de doenças imunopreveníveis. O PNI tem conseguindo bons resultados em termos de cobertura vacinais e controle de importantes doenças, embora ainda com importantes desigualdades regionais e locais. Este estudo busca conhecer os fatores que determinam a efetividade deste programa no município de São Paulo a partir de uma análise mutinível. MÉTODO: Em 2002 o Depto. de Medicina Social da FCMSCSP realizou o Inquérito de Cobertura Vacinal no primeiro ano de vida para a coorte de nascidos entre 1º de novembro de 1999 e 31 de outubro de 2000 residentes no município de São Paulo. Este inquérito domiciliar se baseou no processo de amostragem por conglomerado preconizado pela OPAS. Em cada um dos 41 Distritos de Saúde (DS) foi calculada uma amostra de 210 crianças, num total de 8610 crianças. A importância de variáveis grupais e individuais em relação a cobertura vacinal para esquema completo em crianças com um ano de idade e a participação no Dia Nacional de Vacinação (25/08/2001) foi investigada através de um modelo multinível logístico. Foram estabelecidos nesta análise três níveis: individual, conglomerado, compostos pelos setores censitários e decorrentes do processo de análise e o DS. O modelo multinível foi construído através do software MLWin 2.0. RESULTADOS: O modelo multinível para cobertura com esquema completo em crianças com um ano de idade evidenciou um efeito do DS de 0,15 com um p <0,01; um efeito do conglomerado de 0,07 e p=0,051.A inclusão das variáveis individuais quase não alterou os efeitos aleatórios dos dois níveis. No modelo final as seguintes variáveis mostraram-se associadas ao desfecho: uso de serviço privado OR de 0,64 (IC95%0,50-0,82), pessoas por cômodo um OR de 0,93 (IC95%;0,88-0,98), mãe trabalhar fora e escolaridade da mãe estiveram associadas ao desfecho e apresentaram uma interação.Os dados sugerem uma tendência de aumento da cobertura vacinal conforme aumenta a escolaridade da mãe até a categoria de 9 a 11 anos, voltando a ser menor em crianças com mães um nível de estudo maior. Em relação a participação em campanha de vacinação, o nível do DS apresentou um efeito de 0,32, e nível do conglomerado de 0,18 (p<0,001). Em relação as variáveis individuais, uso de serviço privado para vacinar apresentou um OR de 0,26 (IC95%: 0,21-0,36), mãe trabalha fora de casa um OR de 0,82 (IC95%:0,73-0,92) A escolaridade da mãe, usando a faixa de 9 a 11 anos de escolaridade da mãe por referência, apresentou até a terceira série OR de 0,97 (IC95%: 0,76-1,23), de 4 a 8 anos um OR de 0,86 (IC95%:0,75-0,98) e mais 12 anos de estudo um OR de 0,54 (IC95%:0,44-0,66). A participação em campanha foi maior conglomerados com menor renda média do chefe e no DS com maior proporção de pobres. CONCLUSÕES: Existem diferenças em relação à cobertura vacinal no município de São Paulo que não são totalmente explicadas pelas características individuais e familiares. O DS de moradia destas famílias possui um efeito de contexto sobre a cobertura vacinal. A participação em campanhas de vacinação se revela uma importante estratégia para o acesso dos segmentos menos favorecidos às vacinas. É necessário também aprofundar o conhecimento sobre a cobertura vacinal nos segmentos mais abastados do município / INTRODUCTION: In Brazil, the National Immunization Program (PNI), a branch of the National Surveillance System, is the standard approach of the Brazilian Unified Health System to control, eliminate and even eradicate a set of vaccine-preventable diseases. The PNI has attained good results in terms of vaccine coverage and controlling important diseases, although local and regional inequalities persist. This study aimed to identify which factors were influencing the effectiveness of immunization program in São Paulo City, using multilevel analysis. METHODS: In 2002 the Social Medicine Department of Santa Casa School of Medical Sciences (FCMSC) carried out a vaccine coverage survey, among residents of São Paulo City, addressing the vaccines recommended for the first year of life, among children born between November 1 of 1999 and October 31 of 2000. This household survey was done using the cluster sample technique advocated by the PAHO. In each one of the 41 Health Districts (DS) a sample of 210 infants, in a gross one of 8610, was obtained. The role of group and individuals variable levels in the vaccine coverage for the complete schedule among infants of one year of age and the participation in the National Vaccination Day (25/08/2001) were investigated through a logistic multilevel model. The analysis was performed including three levels: individual, cluster and health districts (DS). The cluster was based on the census tracts, defined by the sampling procedures. The multilevel model was performed using MLWin 2.0. software. RESULTS: The multilevel model for complete coverage with the recommended vaccines for the age group (children aged up to one year), identified at the health district (DS) an effect of 0,15 (p-value <0,01) and at the cluster level an effect of 0,07 (p=0,051). Adding individual level variables did not change the random effects of the two other levels. The final model included the following variables associated to the outcome: use of private service , (OR= 0,64, 95%CI: 0,50-0,82), number of persons by room (agglomerate), (OR= 0,93, 95%CI: 0,88-0,98). The employment status of the mother and mother\'s level of education, were both associated to the outcome and presented an interaction. Our data suggests the immunization uptake increases as the mother\'s years of education increases up to 9 to 11 years, decreasing among children whose mothers have greater level than 11 years of schooling. Regarding participation in vaccination campaign, at the DS level, the effect was 0,32, and at the cluster level the effect was 0,18 (p<0,001). At the individual level, the following characteristics were associated to the outcome: use of private clinic for vaccination (OR=0,26, 95% CI: 0,21-0,36), a working mother (OR=0,82, 95% CI:0,73-0,92). To examine the effect of mother\'s education, we used 9 to 11 years of education as the reference category. For children whose mothers had up to 3 years of education the OR was 0,97 (95% CI: 0,76-1,23); from 4 to 8 years of education the OR was 0,86 (95% CI:0,75-0,98) and for more than 12 years of study an OR of 0,54 (95% CI:0,44-0,66). The participation in campaign was bigger in clusters with lower head of household income, and bigger proportion of poor population. CONCLUSIONS: There are differences in the immunization uptake in São Paulo City that cannot be fully explained by the family and individual characteristics. The Health District, a geographic area where the household is located, poses a context effect on the vaccine coverage. Vaccine campaigns have an important role in increasing the access to vaccines for the poorest population. It is necessary further studies to a better understanding of the vaccine coverage in the wealthier segments of the town

Page generated in 0.1606 seconds