Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Detecting Differences Between Correlation-Matrix Populations due to
  Single-variable Perturbations, with Application to Resting State fMRI   Correlation matrices provide a useful way to characterize variable
dependencies in many real-world problems. Often, a perturbation in few
variables can lead to small differences in multiple correlation coefficients
related to these variables. In this paper we propose a low-dimensional
representation of these differences as a product of single-variable
perturbations that can efficiently characterize such effects; We develop
methods for point estimation, confidence intervals and hypothesis tests for
this model. Importantly, our methods are tailored for comparing samples of
correlation matrices, in that they account for both the inherent variability in
correlation matrices and for the variation between matrices in each sample. In
simulations, our model shows a substantial increase in power compared to mass
univariate approaches.
  As a test case, we analyze correlation matrices of resting state
functional-MRI (RS-fMRI) in patients with a rare neurological condition -
transient global amnesia (TGA) and healthy controls. TGA is characterized by a
lesion to a specific brain area and the connectivity matrices supposedly
represent changes in only few variables, as in the assumption of our model. In
this dataset, our model identifies substantially decreased synchronization in
several brain regions within the patient population, which could not be
detected using previous methods without prior-knowledge. Our framework shows
the advantage of adding informed mean-structure for detecting differences in
high-dimensional correlation matrices, and can be adapted for new differential
structures. Our methods are available in the open-source package corrpops.

30
The categories of this paper are: q-alg
14
The categories of this paper are: math-ph
33
The categories of this paper are: plasm-ph
35
The categories of this paper are: mtrl-th
7
The categories of this paper are: hep-th
19
The categories of this paper are: eess
20
The categories of this paper are: acc-phys
6
The categories of this paper are: astro-ph
32
The categories of this paper are: atom-ph
1
The categories of this paper are: cs
25
The categories of this paper are: patt-sol
18
The categories of this paper are: econ
12
The categories of this paper are: nucl-th
5
The categories of this paper are: gr-qc
11
The categories of this paper are: hep-lat
13
The categories of this paper are: quant-ph