Robust estimation and hypothesis testing in microarray analysis

Download
2010
Ülgen, Burçin Emre
Microarray technology allows the simultaneous measurement of thousands of gene expressions simultaneously. As a result of this, many statistical methods emerged for identifying differentially expressed genes. Kerr et al. (2001) proposed analysis of variance (ANOVA) procedure for the analysis of gene expression data. Their estimators are based on the assumption of normality, however the parameter estimates and residuals from this analysis are notably heavier-tailed than normal as they commented. Since non-normality complicates the data analysis and results in inefficient estimators, it is very important to develop statistical procedures which are efficient and robust. For this reason, in this work, we use Modified Maximum Likelihood (MML) and Adaptive Maximum Likelihood estimation method (Tiku and Suresh, 1992) and show that MML and AMML estimators are more efficient and robust. In our study we compared MML and AMML method with widely used statistical analysis methods via simulations and real microarray data sets.

Suggestions

Robust Attitude Estimation Using IMU-Only Measurements
Candan, Batu; Söken, Halil Ersin (2021-01-01)
© 1963-2012 IEEE.This article proposes two novel covariance-tuning methods to form a robust Kalman filter (RKF) algorithm for attitude (i.e., roll and pitch) estimation using the measurements of only an inertial measurement unit (IMU). KF-based and complementary filtering (CF)-based approaches are the two common methods for solving the attitude estimation problem. Efficiency and optimality of the KF-based attitude filters are correlated with appropriate tuning of the covariance matrices. Manual tuning proce...
Variable Selection and Classification for Longitudinal Binary Data Through Three-Step Sparse Boosting
Emer, Deniz Esin; İlk Dağ, Özlem; Department of Statistics (2022-6)
With the rapid evolution of technology, it is now possible to obtain the gene expression levels of thousands of genes in a single experiment. In these experiments, the sample size is relatively small but the number of covariates under consideration is extremely large, whereas only a small number of expressions may be related to the outcome of interest. Hence, the selection of causal features is much-needed along with the model estimation. In this thesis, we propose a three-step sparse boosting model for det...
Deep Learning in the Presence of Label Noise: A Meta-Learning Approach
Algan, Görkem; Ulusoy, İlkay; Department of Electrical and Electronics Engineering (2021-3-12)
Image classification systems recently made a giant leap with the advancement of deep neural networks. However, these systems require an excessive amount of labeled data to be adequately trained. Gathering a correctly annotated dataset is not always feasible due to practical challenges. Because of these practical challenges, label noise is a common problem in real-world datasets. This thesis presents two novel label noise robust learning algorithms: MSLG (Meta Soft Label Generation) and MetaLabelNet. Both al...
ADAPTIVE IDENTIFICATION OF OSCILLATORY BANDS FROM SUBCORTICAL NEURAL DATA
Özkurt, Tolga Esat; Hirschmann, Jan; Schnitzler, Alfons (2015-09-04)
Neural oscillations in various distinct frequency bands and their interrelations yield high temporal resolution signatures of the human brain activity. This study demonstrates solutions to some of the common challenges in the analysis of neurophysiological data by means of subthalamic local field potentials (LFP) acquired form patients with Parkinson's Disease (PD) undergoing deep brain stimulation therapy. Multivariate empirical mode decomposition (MEMD), being a data-driven method suitable for multichanne...
Neural network based orbit prediction for a geostationary satellite
Kutay, Ali Türker; Tulunay, Ersin; Tekinalp, Ozan (null; 2001-05-23)
An artificial Neural Network (NN) model was developed to estimate the semi-major axis (a), the eccentricity (e) and the inclination (i) of a geostationary satellite orbit. To facilitate a comparison between the NN model developed herewith and a real case, the TORKSAT lB geostationary satellite has been taken as example. A code that numerically solves the parameters of the TORKSAT's orbit, namely METUAEE1, is used to generate the training data for the NN model and to evaluate its performance. A Multi-La...
Citation Formats
B. E. Ülgen, “Robust estimation and hypothesis testing in microarray analysis,” Ph.D. - Doctoral Program, Middle East Technical University, 2010.