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Full-Text Articles in Physical Sciences and Mathematics

Regressing Scalar Outcomes On Image Predictors Via Functional Principal Component Regression, Philip T. Reiss Nov 2008

Regressing Scalar Outcomes On Image Predictors Via Functional Principal Component Regression, Philip T. Reiss

Philip T. Reiss

No abstract provided.


Simultaneous Confidence Bands For The Coefficient Function In Functional Regression, Philip T. Reiss Aug 2008

Simultaneous Confidence Bands For The Coefficient Function In Functional Regression, Philip T. Reiss

Philip T. Reiss

No abstract provided.


Inferring Group Differences In Brain Connectivity From Functional Magnetic Resonance Images, Philip T. Reiss Jul 2008

Inferring Group Differences In Brain Connectivity From Functional Magnetic Resonance Images, Philip T. Reiss

Philip T. Reiss

No abstract provided.


Reliability Of Functional Connectivity Networks: How Can We Assess It?, Philip T. Reiss Jul 2008

Reliability Of Functional Connectivity Networks: How Can We Assess It?, Philip T. Reiss

Philip T. Reiss

No abstract provided.


Writing Research Proposal: Literature Review And Database Search, Mamoudou H. Dicko Prof. May 2008

Writing Research Proposal: Literature Review And Database Search, Mamoudou H. Dicko Prof.

Pr. Mamoudou H. DICKO, PhD

The maiden proposed research project should demonstrate that the present study will add a significant knowledge on the subject. The main objective of the literature research is to allow that the statement of the research need will clearly establish the objective of the new study.


The T-Mixture Model Approach For Detecting Differentially Expressed Genes In Microarrays, Shuo Jiao, Shunpu Zhang Jan 2008

The T-Mixture Model Approach For Detecting Differentially Expressed Genes In Microarrays, Shuo Jiao, Shunpu Zhang

Shuo Jiao

The finite mixture model approach has attracted much attention in analyzing microarray data due to its robustness to the excessive variability which is common in the microarray data. Pan (2003) proposed to use the normal mixture model method (MMM) to estimate the distribution of a test statistic and its null distribution. However, considering the fact that the test statistic is often of t-type, our studies find that the rejection region from MMM is often significantly larger than the correct rejection region, resulting an inflated type I error. This motivates us to propose the t-mixture model (TMM) approach. In this paper, …


Multinomial Logistic Regression: An Application To Estimating Performance Of A Multiple Screening Test For Bowel Cancer When Negatives Are Unverified., Chris Lloyd, Don Frommer Dec 2007

Multinomial Logistic Regression: An Application To Estimating Performance Of A Multiple Screening Test For Bowel Cancer When Negatives Are Unverified., Chris Lloyd, Don Frommer

Chris J. Lloyd

This paper describes a method of estimating the performance of a multiple screening test where those who test negative do not have their true disease status determined. The methodology is motivated by a dataset on 49,927 subjects who were given K=6 binary tests for bowel cancer. A complicating factor is that individuals may have polyps present in the bowel, a condition that the screening test is not designed to detect but which may be worth diagnosing. The methodology is based on a multinomial logit model for Pr(S|R_6), the probability distribution of patient status S (healthy, polyps or diseased) conditional on …


A New Exact And More Powerful Unconditional Test Of No Treatment Effect From Binary Matched Pairs, Chris Lloyd Dec 2007

A New Exact And More Powerful Unconditional Test Of No Treatment Effect From Binary Matched Pairs, Chris Lloyd

Chris J. Lloyd

We consider the problem of testing for a difference in the probability of success from matched binary pairs. Starting with three standard inexact tests, the nuisance parameter is first estimated and then the residual dependence is eliminated by maximisation, producing what I call an E+M P-value. The E+M P-value based on McNemar's statistic is shown numerically to dominate previous suggestions, including partially maximised P-values as described in Berger and Sidik (2003). The latter method however may have computational advantages for large samples.


Long-Term Consequences Of The Delay Between Virologic Failure Of Highly Active Antiretroviral Therapy And Regimen Modification, Maya L. Petersen, Mark J. Van Der Laan, Napravnik Sonia, Joseph J. Eron, Richard G. Moore, Steven G. Deeks Dec 2007

Long-Term Consequences Of The Delay Between Virologic Failure Of Highly Active Antiretroviral Therapy And Regimen Modification, Maya L. Petersen, Mark J. Van Der Laan, Napravnik Sonia, Joseph J. Eron, Richard G. Moore, Steven G. Deeks

Maya Petersen

Objectives: Current treatment guidelines recommend immediate modification of antiretroviral therapy in HIV-infected individuals with incomplete viral suppression. These recommendations have not been tested in observational studies or large randomized trials. We evaluated the consequences of delayed modification following virologic failure. Design/methods: We used prospective data from two clinical cohorts to estimate the effect of time until regimen modification following first regimen failure on all-cause mortality. The impact of regimen type was also assessed. As the effect of delayed switching can be confounded if patients with a poor prognosis modify therapy earlier than those with a good prognosis, we used a …


Functional Generalized Linear Models With Applications To Neuroimaging, Philip T. Reiss, R. Todd Ogden Dec 2007

Functional Generalized Linear Models With Applications To Neuroimaging, Philip T. Reiss, R. Todd Ogden

Philip T. Reiss

No abstract provided.