joint structure
Joint Linked Component Analysis for Multiview Data
Recent technological advances have led to increased availability of multiple sources of highcontent data. In particular, multiview data refers to different types of variables collected from the same set of individuals. One typical example is the Roadmap Epigenomics Project (Kundaje et al., 2015) which integrates information about histone marks, DNA methylation, DNA accessibility and RNA expression to infer high-resolution maps of regulatory elements annotated jointly across a total of 127 reference epigenomes spanning diverse cell and tissue types. Another example is the data used in NCI-DREAM drug sensitivity prediction challenge (Costello et al. (2014)) which contains gene expression (GE), RNA, DNA methylation (MET), copy number variation (CNV), protein abundance (RPPA) and exome sequence (EX) measurements for 53 human breast cancer cell lines. The prevalence of multiview data has motivated research on uncovering associations between different data views.
A continuum robot inspired by elephant trunks
Conventional robots based on separate joints do not always perform well in complex real-world tasks, particularly those that involve the dexterous manipulation of objects. Some roboticists have thus been trying to devise continuum robots, robotic platforms characterized by infinite degrees of freedom and no fixed number of joints. Continuum robots are typically based on cables or other deformable components that can move more freely and are not restricted by fixed joint structures. Despite these advantages, many continuum robot designs proposed still cannot yet efficiently navigate complex and unstructured environments. Researchers at Sun Yat-Sen University, Dalian University of Technology and London South Bank University have recently developed a new continuum robot inspired by the trunks of elephants.
Non-Euclidean Analysis of Joint Variations in Multi-Object Shapes
Liu, Zhiyuan, Schulz, Jรถrn, Taheri, Mohsen, Styner, Martin, Damon, James, Pizer, Stephen, Marron, J. S.
This paper considers joint analysis of multiple functionally related structures in classification tasks. In particular, our method developed is driven by how functionally correlated brain structures vary together between autism and control groups. To do so, we devised a method based on a novel combination of (1) non-Euclidean statistics that can faithfully represent non-Euclidean data in Euclidean spaces and (2) a non-parametric integrative analysis method that can decompose multi-block Euclidean data into joint, individual, and residual structures. We find that the resulting joint structure is effective, robust, and interpretable in recognizing the underlying patterns of the joint variation of multi-block non-Euclidean data. We verified the method in classifying the structural shape data collected from cases that developed and did not develop into Autistic Spectrum Disorder (ASD).
Double-matched matrix decomposition for multi-view data
Yuan, Dongbang, Gaynanova, Irina
We consider the problem of extracting joint and individual signals from multi-view data, that is data collected from different sources on matched samples. While existing methods for multi-view data decomposition explore single matching of data by samples, we focus on double-matched multi-view data (matched by both samples and source features). Our motivating example is the miRNA data collected from both primary tumor and normal tissues of the same subjects; the measurements from two tissues are thus matched both by subjects and by miRNAs. Our proposed double-matched matrix decomposition allows to simultaneously extract joint and individual signals across subjects, as well as joint and individual signals across miRNAs. Our estimation approach takes advantage of double-matching by formulating a new type of optimization problem with explicit row space and column space constraints, for which we develop an efficient iterative algorithm. Numerical studies indicate that taking advantage of double-matching leads to superior signal estimation performance compared to existing multi-view data decomposition based on single-matching. We apply our method to miRNA data as well as data from the English Premier League soccer matches, and find joint and individual multi-view signals that align with domain specific knowledge.
Joint and individual variation explained (JIVE) for integrated analysis of multiple data types
Lock, Eric F., Hoadley, Katherine A., Marron, J. S., Nobel, Andrew B.
Research in several fields now requires the analysis of data sets in which multiple high-dimensional types of data are available for a common set of objects. In particular, The Cancer Genome Atlas (TCGA) includes data from several diverse genomic technologies on the same cancerous tumor samples. In this paper we introduce Joint and Individual Variation Explained (JIVE), a general decomposition of variation for the integrated analysis of such data sets. The decomposition consists of three terms: a low-rank approximation capturing joint variation across data types, low-rank approximations for structured variation individual to each data type, and residual noise. JIVE quantifies the amount of joint variation between data types, reduces the dimensionality of the data and provides new directions for the visual exploration of joint and individual structures. The proposed method represents an extension of Principal Component Analysis and has clear advantages over popular two-block methods such as Canonical Correlation Analysis and Partial Least Squares. A JIVE analysis of gene expression and miRNA data on Glioblastoma Multiforme tumor samples reveals gene-miRNA associations and provides better characterization of tumor types. Data and software are available at https://genome.unc.edu/jive/