Publications
Characterization of disinformation networks using graph embeddings and opinion mining
Summary
Summary
Global social media networks' omnipresent access, real time responsiveness and ability to connect with and influence people have been responsible for these networks' sweeping growth. However, as an unintended consequence, these defining characteristics helped create a powerful new technology for spread of propaganda and false information. We present a novel...
Investigation of the relationship of vocal, eye-tracking, and fMRI ROI time-series measures with preclinical mild traumatic brain injury
Summary
Summary
In this work, we are examining correlations between vocal articulatory features, ocular smooth pursuit measures, and features from the fMRI BOLD response in regions of interest (ROI) time series in a high school athlete population susceptible to repeated head impact within a sports season. Initial results have indicated relationships between...
Multi-Objective Graph Matching via Signal Filtering
Summary
Summary
In this white paper we propose a new method which exploits tools from graph signal processing to solve the graph matching problem, the problem of estimating the correspondence between the vertex sets of two graphs. We recast the graph matching problem as matching multiple similarity matrices where the similarities are...
An Eye on the Storm: Tracking Power Outages via the Internet of Things
Summary
Summary
Assessing the extent of power outages in the wake of disasters is a crucial but daunting challenge. We developed a prototype to estimate and map the severity and location of power outages throughout an event by taking advantage of IoT as a non-traditional power-sensing network. We present results used by...
Uncovering human trafficking networks through text analysis
Summary
Summary
Human trafficking is a form of modern-day slavery affecting an estimated 40 million victims worldwide, primarily through the commercial sexual exploitation of women and children. In the last decade, the advertising of victims has moved from the streets to websites on the Internet, providing greater efficiency and anonymity for sex...
Corpora design and score calibration for text dependent pronunciation proficiency recognition
Summary
Summary
This work investigates methods for improving a pronunciation proficiency recognition system, both in terms of phonetic level posterior probability calibration, and in ordinal utterance level classification, for Modern Standard Arabic (MSA), Spanish and Russian. To support this work, utterance level labels were obtained by crowd-sourcing the annotation of language learners'...
Using K-means in SVR-based text difficulty estimation
Summary
Summary
A challenge for second language learners, educators, and test creators is the identification of authentic materials at the right level of difficulty. In this work, we present an approach to automatically measure text difficulty, integrated into Auto-ILR, a web-based system that helps find text material at the right level for...
State-of-the-art speaker recognition for telephone and video speech: the JHU-MIT submission for NIST SRE18
Summary
Summary
We present a condensed description of the joint effort of JHUCLSP, JHU-HLTCOE, MIT-LL., MIT CSAIL and LSE-EPITA for NIST SRE18. All the developed systems consisted of xvector/i-vector embeddings with some flavor of PLDA backend. Very deep x-vector architectures–Extended and Factorized TDNN, and ResNets– clearly outperformed shallower xvectors and i-vectors. The...
Improving robustness to attacks against vertex classification
Summary
Summary
Vertex classification—the problem of identifying the class labels of nodes in a graph—has applicability in a wide variety of domains. Examples include classifying subject areas of papers in citation networks or roles of machines in a computer network. Recent work has demonstrated that vertex classification using graph convolutional networks is...
Discriminative PLDA for speaker verification with X-vectors
Summary
Summary
This paper proposes a novel approach to discriminative training ofprobabilistic linear discriminant analysis (PLDA) for speaker veri-fication with x-vectors. The Newton Method is used to discrimi-natively train the PLDA model by minimizing the log loss of ver-ification trials. By diagonalizing the across-class and within-classcovariance matrices as a pre-processing step, the...