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Full-Text Articles in Biostatistics

Promoting Similarity Of Model Sparsity Structures In Integrative Analysis Of Cancer Genetic Data, Shuangge Ma Dec 2014

Promoting Similarity Of Model Sparsity Structures In Integrative Analysis Of Cancer Genetic Data, Shuangge Ma

Shuangge Ma

In profiling studies, the analysis of a single dataset often leads to unsatisfactory results because of the small sample size. Multi-dataset analysis utilizes information across multiple independent datasets and outperforms single-dataset analysis. Among the available multi-dataset analysis methods, integrative analysis methods aggregate and analyze raw data and outperform meta-analysis methods, which analyze multiple datasets separately and then pool summary statistics. In this study, we conduct integrative analysis and marker selection under the heterogeneity structure, which allows different datasets to have overlapping but not necessarily identical sets of markers. Under certain scenarios, it is reasonable to expect some similarity of identified …


A Penalized Robust Semiparametric Approach For Gene-Environment Interactions, Shuangge Ma Dec 2014

A Penalized Robust Semiparametric Approach For Gene-Environment Interactions, Shuangge Ma

Shuangge Ma

In genetic and genomic studies, gene-environment (G*E) interactions have important implications. Some of the existing G$\times$E interaction methods are limited by analyzing a small number of G factors at a time, by assuming linear effects of E factors, by assuming no data contamination, and by adopting ineffective selection techniques. In this study, we propose a new approach for identifying important G*E interactions. It jointly models the effects of all E and G factors and their interactions. A partially linear varying coefficient model (PLVCM) is adopted to accommodate possible nonlinear effects of E factors. A rank-based loss function is used to …


Integrative Analysis Of Prognosis Data On Multiple Cancer Subtypes, Shuangge Ma Dec 2012

Integrative Analysis Of Prognosis Data On Multiple Cancer Subtypes, Shuangge Ma

Shuangge Ma

In cancer research, profiling studies have been extensively conducted, searching for genes/SNPs associated with prognosis. Cancer is diverse. Examining similarity and difference in the genetic basis of multiple subtypes of the same cancer can lead to a better understanding of their connections and distinctions. Classic meta-analysis methods analyze each subtype separately and then compare analysis results across subtypes. Integrative analysis methods, in contrast, analyze the raw data on multiple subtypes simultaneously and can outperform meta-analysis methods. In this study, prognosis data on multiple subtypes of the same cancer are analyzed. An AFT (accelerated failure time) model is adopted to describe …


Incorporating Network Structure In Integrative Analysis Of Cancer Prognosis Data, Shuangge Ma Dec 2011

Incorporating Network Structure In Integrative Analysis Of Cancer Prognosis Data, Shuangge Ma

Shuangge Ma

In high-throughput cancer genomic studies, markers identified from the analysis of single datasets may have unsatisfactory properties because of low sample sizes. Integrative analysis pools and analyzes raw data from multiple studies, and can effectively increase sample size and lead to improved marker identification results. In this study, we consider the integrative analysis of multiple high-throughput cancer prognosis studies. In the existing integrative analysis studies, the interplay among genes, which can be described using the network structure, has not been effectively accounted for. In network analysis, tightly-connected nodes (genes) are more likely to have related biological functions and similar regression …


Risk Factors Of Follicular Lymphoma, Shuangge Ma Dec 2011

Risk Factors Of Follicular Lymphoma, Shuangge Ma

Shuangge Ma

No abstract provided.


Health Insurance Coverage And Impact: A Survey In Three Cities In China, Shuangge Ma Dec 2011

Health Insurance Coverage And Impact: A Survey In Three Cities In China, Shuangge Ma

Shuangge Ma

No abstract provided.


Integrative Analysis Of Multiple Cancer Genomic Datasets Under The Heterogeneity Model, Shuangge Ma Dec 2011

Integrative Analysis Of Multiple Cancer Genomic Datasets Under The Heterogeneity Model, Shuangge Ma

Shuangge Ma

No abstract provided.


Health Insurance Coverage, Medical Expenditure And Coping Strategy: Evidence From Taiwan, Shuangge Ma Dec 2011

Health Insurance Coverage, Medical Expenditure And Coping Strategy: Evidence From Taiwan, Shuangge Ma

Shuangge Ma

No abstract provided.


Impact Of Illness And Medical Expenditure On Household Consumptions: A Survey In Western China, Shuangge Ma Dec 2011

Impact Of Illness And Medical Expenditure On Household Consumptions: A Survey In Western China, Shuangge Ma

Shuangge Ma

No abstract provided.


Identification Of Gene-Environment Interactions In Cancer Prognosis Studies Using Penalization, Shuangge Ma Dec 2011

Identification Of Gene-Environment Interactions In Cancer Prognosis Studies Using Penalization, Shuangge Ma

Shuangge Ma

High-throughput cancer studies have been extensively conducted, searching for genetic risk factors independently associated with prognosis beyond clinical and environmental risk factors. Many studies have shown that the gene-environment interactions may have important implications. Some of the existing methods, such as the commonly adopted single-marker analysis, may be limited in that they cannot accommodate the joint effects of a large number of genetic markers or use ineffective marker identification techniques. In this study, we analyze cancer prognosis studies, and adopt the AFT (accelerated failure time) model to describe survival. A weighted least squares approach, which has the lowest computational cost, …


Integrative Analysis Of Cancer Genomic Data, Shuangge Ma Sep 2009

Integrative Analysis Of Cancer Genomic Data, Shuangge Ma

Shuangge Ma

In the past decade, we have witnessed a period of unparallel development in the field of cancer genomics. To address the same or similar biomedical questions, multiple cancer genomic studies have been independently designed and conducted. Cancer gene signatures identified from analysis of individual datasets often have low reproducibility. A cost-effective way of improving reproducibility is to conduct integrative analysis of datasets from multiple studies with comparable designs. To properly integrate multiple studies and conduct integrative analysis, we need to access various public data warehouses, retrieve experiment protocols and raw data, evaluate individual studies and select those with comparable designs, …


Identification Of Cancer-Associated Gene Pathways From Analysis Of Expression Data, Shuangge Ma Aug 2009

Identification Of Cancer-Associated Gene Pathways From Analysis Of Expression Data, Shuangge Ma

Shuangge Ma

No abstract provided.


Lecture 5, Shuangge Ma Jun 2009

Lecture 5, Shuangge Ma

Shuangge Ma

No abstract provided.


Final Project, Shuangge Ma Jun 2009

Final Project, Shuangge Ma

Shuangge Ma

No abstract provided.


Lecture 4, Shuangge Ma Jun 2009

Lecture 4, Shuangge Ma

Shuangge Ma

No abstract provided.


Lecture 4, Shuangge Ma Jun 2009

Lecture 4, Shuangge Ma

Shuangge Ma

No abstract provided.


Computer Intensive Methods Lecture 13, Shuangge Ma Jun 2009

Computer Intensive Methods Lecture 13, Shuangge Ma

Shuangge Ma

No abstract provided.


Final Project (Description), Shuangge Ma Jun 2009

Final Project (Description), Shuangge Ma

Shuangge Ma

No abstract provided.


Final Project (Data), Shuangge Ma Jun 2009

Final Project (Data), Shuangge Ma

Shuangge Ma

No abstract provided.


Lecture 3, Shuangge Ma Jun 2009

Lecture 3, Shuangge Ma

Shuangge Ma

No abstract provided.


Lecture 2, Shuangge Ma Jun 2009

Lecture 2, Shuangge Ma

Shuangge Ma

No abstract provided.


Reference: Multiple Imputation, Shuangge Ma Jun 2009

Reference: Multiple Imputation, Shuangge Ma

Shuangge Ma

No abstract provided.


Reference: Weighted Bootstrap, Shuangge Ma Jun 2009

Reference: Weighted Bootstrap, Shuangge Ma

Shuangge Ma

No abstract provided.


Computer Intensive Methods Lecture 9, Shuangge Ma Jun 2009

Computer Intensive Methods Lecture 9, Shuangge Ma

Shuangge Ma

No abstract provided.


Computer Intensive Methods Lecture 8, Shuangge Ma Jun 2009

Computer Intensive Methods Lecture 8, Shuangge Ma

Shuangge Ma

No abstract provided.


Reference: Counter Examples [Bootstrap], Shuangge Ma Jun 2009

Reference: Counter Examples [Bootstrap], Shuangge Ma

Shuangge Ma

No abstract provided.


Computer Intensive Methods Lecture 7 (Lab 2), Shuangge Ma Jun 2009

Computer Intensive Methods Lecture 7 (Lab 2), Shuangge Ma

Shuangge Ma

No abstract provided.


Computer Intensive Methods Lecture 6, Shuangge Ma Jun 2009

Computer Intensive Methods Lecture 6, Shuangge Ma

Shuangge Ma

No abstract provided.


Reference: Block Jackknife, Shuangge Ma Jun 2009

Reference: Block Jackknife, Shuangge Ma

Shuangge Ma

No abstract provided.


Computer Intensive Methods Lecture 5, Shuangge Ma Jun 2009

Computer Intensive Methods Lecture 5, Shuangge Ma

Shuangge Ma

No abstract provided.