SCIENTIFIC PROGRAMS AND ACTIVITIES

December 22, 2024

CONNECTING WOMEN IN MATHEMATICS ACROSS CANADA
December 7-8, 2006

Talk Abstracts

Shaheena Bashir, McMaster University
Permutation Tests in Gene Microarrays
Gene microarrays study is a burgeoning & challenging field. The purpose is to identify the differentially expressed genes to identify the causes of some disease, etc. The challenges occur due to a number of reasons; gene expressions for a very large number of genes are available as compared to very small sample size, and possibility of high level of non-normal random noises. Permutation tests are useful in this context when traditional ANOVA can not be used. In this talk, I will discuss how permutation tests can be constructed to test the hypotheses of differential expressions in microarrays.

Kadiri, Habiba - University of Montreal
Effective estimates of some prime counting functions and applications
It is widely expected that every integer may be represented as a sum of seven cubes. In 1943, Linnik proved that it was true for sufficiently large integers. The problem of finding the size of the smallest integer for which it is true is related to some effective estimates on prime counting functions. I will discuss an explicit version of Vinogradov's theorem on the sum of three primes and how it is also related to the distribution of prime numbers.

Kim, Hee Jung - McMaster University
Topological triviality of smoothly knotted surfaces in 4-manifolds
Some generalizations of the Fintushel-Stern rim surgery are known to produce smoothly knotted surfaces. We show that if the fundamental groups of their complements are standard, then these surfaces are topologically unknotted.

Labibi, Batool - University of Alberta
Decentralized Stabilization of a Class of Nonlinear Interconnected Systems
This work considers decentralized output feedback stabilization of a class of nonlinear interconnected systems using linear matrix inequalities. Based on small gain theorem, sufficient condition for closed-loop stability is derived. By solving an appropriately defined LMI problem, a decentralized output feedback controller is designed and an estimation for the attraction domain of the nonlinear system is given. An application to a large scale telescope is given to show the effectiveness of the proposed methodology.

Masuda, Ariane Carleton University
Analogies between the ring of integers and the ring of polynomials over a finite field
In this talk we compare and contrast the ring of integers and the ring of polynomials over a finite field. We discuss several questions which have analogous versions in both settings.

Pullenayegum, Eleanor - University of Waterloo
Cost-effectiveness analysis in clinical trials and longitudinal data: filling in some gaps
In a country with ever-increasing health spending, studying the cost-effectiveness analysis of medical therapies is a vital area of health research. As health researchers designed trials to assess cost-effectiveness and gather data, statisticians began to wonder how to analyse this type of data: cost data has several features that make it difficult to model using standard statistical methods. Whilst the necessary statistical methods now exist, there are existing statistical ideas --some very basic -- that can be used to improve the efficiency of estimation considerably.

Savu, Anamaria - University of Northern British Columbia
Some remarks on the solid-on-solid model
Matching priors are a natural choice in the absence of specific prior information, since they lead to inferences equivalent to frequentist inferences to the second order. When the model depends on a scalar parameter, Jeffrey’s prior is the unique first order matching prior. However, when the model depends on a vector parameter, the matching priors (not unique) are obtained as solutions to a complicated system of differential equations. In this talk we show the uniqueness of a first order probability matching prior for purposes of higher order approximate inference for parametric settings with a scalar component of interest. We exemplify by a simulation study and a numerical example.

CONNECTING WOMEN IN MATHEMATICS ACROSS CANADA
December 7-8, 2006