BEGIN:VCALENDAR VERSION:2.0 PRODID:-//128.220.36.25//NONSGML kigkonsult.se iCalcreator 2.26.9// CALSCALE:GREGORIAN METHOD:PUBLISH X-FROM-URL:https://www.clsp.jhu.edu X-WR-TIMEZONE:America/New_York BEGIN:VTIMEZONE TZID:America/New_York X-LIC-LOCATION:America/New_York BEGIN:STANDARD DTSTART:20231105T020000 TZOFFSETFROM:-0400 TZOFFSETTO:-0500 RDATE:20241103T020000 TZNAME:EST END:STANDARD BEGIN:DAYLIGHT DTSTART:20240310T020000 TZOFFSETFROM:-0500 TZOFFSETTO:-0400 RDATE:20250309T020000 TZNAME:EDT END:DAYLIGHT END:VTIMEZONE BEGIN:VEVENT UID:ai1ec-21270@www.clsp.jhu.edu DTSTAMP:20240329T044324Z CATEGORIES;LANGUAGE=en-US:Student Seminars CONTACT: DESCRIPTION:Abstract\nSocial media allows researchers to track societal and cultural changes over time based on language analysis tools. Many of thes e tools rely on statistical algorithms which need to be tuned to specific types of language. Recent studies have questioned the robustness of longit udinal analyses based on statistical methods due to issues of temporal bia s and semantic shift. To what extent are changes in semantics over time af fecting the reliability of longitudinal analyses? We examine this question through a case study: understanding shifts in mental health during the co urse of the COVID-19 pandemic. We demonstrate that a recently-introduced m ethod for measuring semantic shift may be used to proactively identify fai lure points of language-based models and improve predictive generalization over time. Ultimately\, we find that these analyses are critical to produ cing accurate longitudinal studies of social media. DTSTART;TZID=America/New_York:20220207T120000 DTEND;TZID=America/New_York:20220207T131500 LOCATION:In Person or Virtual Option @ https://wse.zoom.us/j/96735183473 @ 234 Ames Hall\, 3400 N. Charles Street\, Baltimore\, MD 21218 SEQUENCE:0 SUMMARY:Student Seminar – Keith Harrigian “The Problem of Semantic Shift in Longitudinal Monitoring of Social Media: A Case Study on Mental Health d uring the COVID-19 Pandemic” URL:https://www.clsp.jhu.edu/events/student-seminar-keith-harrigian-the-pro blem-of-semantic-shift-in-longitudinal-monitoring-of-social-media-a-case-s tudy-on-mental-health-during-the-covid-19-pandemic/ X-COST-TYPE:free X-ALT-DESC;FMTTYPE=text/html:\\n\\n
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\nSocial media allows researchers to track societal and cultural changes over time based on language analysis tools. Many of thes e tools rely on statistical algorithms which need to be tuned to specific types of language. Recent studies have questioned the robustness of longit udinal analyses based on statistical methods due to issues of temporal bia s and semantic shift. To what extent are changes in semantics over time af fecting the reliability of longitudinal analyses? We examine this question through a case study: understanding shifts in mental health during the co urse of the COVID-19 pandemic. We demonstrate that a recently-introduced m ethod for measuring semantic shift may be used to proactively identify fai lure points of language-based models and improve predictive generalization over time. Ultimately\, we find that these analyses are critical to produ cing accurate longitudinal studies of social media.
\n X-TAGS;LANGUAGE=en-US:2022\,February\,Harrigian END:VEVENT BEGIN:VEVENT UID:ai1ec-21487@www.clsp.jhu.edu DTSTAMP:20240329T044324Z CATEGORIES;LANGUAGE=en-US:Seminars CONTACT: DESCRIPTION:Abstract\nEnormous amounts of ever-changing knowledge are avai lable online in diverse textual styles and diverse formats. Recent advance s in deep learning algorithms and large-scale datasets are spurring progre ss in many Natural Language Processing (NLP) tasks\, including question an swering. Nevertheless\, these models cannot scale up when task-annotated t raining data are scarce. This talk presents my lab’s work toward building general-purpose models in NLP and how to systematically evaluate them. Fir st\, I present a general model for two known tasks of question answering i n English and multiple languages that are robust to small domain shifts. Then\, I show a meta-training approach that can solve a variety of NLP tas ks with only using a few examples and introduce a benchmark to evaluate cr oss-task generalization. Finally\, I discuss neuro-symbolic approaches to address more complex tasks by eliciting knowledge from structured data and language models.\n\nBiography\n\nHanna Hajishirzi is an Assistant Profess or in the Paul G. Allen School of Computer Science & Engineering at the Un iversity of Washington and a Senior Research Manager at the Allen Institut e for AI. Her research spans different areas in NLP and AI\, focusing on d eveloping general-purpose machine learning algorithms that can solve many NLP tasks. Applications for these algorithms include question answering\, representation learning\, green AI\, knowledge extraction\, and conversati onal dialogue. Honors include the NSF CAREER Award\, Sloan Fellowship\, Al len Distinguished Investigator Award\, Intel rising star award\, best pape r and honorable mention awards\, and several industry research faculty awa rds. Hanna received her PhD from University of Illinois and spent a year a s a postdoc at Disney Research and CMU. DTSTART;TZID=America/New_York:20220225T120000 DTEND;TZID=America/New_York:20220225T131500 LOCATION:Ames Hall 234 - Presented Virtually Via Zoom https://wse.zoom.us/j /96735183473 SEQUENCE:0 SUMMARY:Hanna Hajishirzi (University of Washington & Allen Institute for AI ) “Toward Robust\, Knowledge-Rich NLP” URL:https://www.clsp.jhu.edu/events/hanna-hajishirzi-university-of-washingt on-allen-institute-for-ai-toward-robust-knowledge-rich-nlp/ X-COST-TYPE:free X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nAbstr act
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\nAdversarial attacks deceive neural network systems by adding carefully crafted perturbations to benign signals. Being almost imperceptible to humans\, these attacks pose a severe security thr eat to the state-of-the-art speech and speaker recognition systems\, makin g it vital to propose countermeasures against them. In this talk\, we focu s on 1) classification of a given adversarial attack into attack algorithm type\, threat model type\, and signal-to-adversarial-noise ratios\, 2) de veloping a novel speech denoising solution to further improve the classifi cation performance.
\nOur proposed approach uses a n x-vector network as a signature extractor to get embeddings\, which we c all signatures. These signatures contain information about the attack and can help classify different attack algorithms\, threat models\, and signal -to-adversarial-noise ratios. We demonstrate the transferability of such s ignatures to other tasks. In particular\, a signature extractor trained to classify attacks against speaker identification can also be used to class ify attacks against speaker verification and speech recognition. We also s how that signatures can be used to detect unknown attacks i.e. attacks not included during training. Lastly\, we propose to improve the signature e xtractor by making the job of the signature extractor easier by removing t he clean signal from the adversarial example (which consists of clean sign al+perturbation). We train our signature extractor using adversarial pertu rbation. At inference time\, we use a time-domain denoiser to obtain adver sarial perturbation from adversarial examples. Using our improved approach \, we show that common attacks in the literature (Fast Gradient Sign Metho d (FGSM)\, Projected Gradient Descent (PGD)\, Carlini-Wagner (CW) ) can be classified with accuracy as high as 96%. We also detect unknown attacks w ith an equal error rate (EER) of about 9%\, which is very promising.
\n X-TAGS;LANGUAGE=en-US:2022\,Joshi\,March END:VEVENT BEGIN:VEVENT UID:ai1ec-21616@www.clsp.jhu.edu DTSTAMP:20240329T044324Z CATEGORIES;LANGUAGE=en-US:Student Seminars CONTACT: DESCRIPTION:Abstract\nSocial media allows researchers to track societal and cultural changes over time based on language analysis tools. Many of thes e tools rely on statistical algorithms which need to be tuned to specific types of language. Recent studies have shown the absence of appropriate tu ning\, specifically in the presence of semantic shift\, can hinder robustn ess of the underlying methods. However\, little is known about the practic al effect this sensitivity may have on downstream longitudinal analyses. W e explore this gap in the literature through a timely case study: understa nding shifts in depression during the course of the COVID-19 pandemic. We find that inclusion of only a small number of semantically-unstable featur es can promote significant changes in longitudinal estimates of our target outcome. At the same time\, we demonstrate that a recently-introduced met hod for measuring semantic shift may be used to proactively identify failu re points of language-based models and\, in turn\, improve predictive gene ralization. DTSTART;TZID=America/New_York:20220318T120000 DTEND;TZID=America/New_York:20220318T131500 LOCATION:Ames Hall 234 @ 3400 N. Charles Street\, Baltimore\, MD 21218 SEQUENCE:0 SUMMARY:Student Seminar – Keith Harrigian “The Problem of Semantic Shift in Longitudinal Monitoring of Social Media” URL:https://www.clsp.jhu.edu/events/student-seminar-keith-harrigian-the-pro blem-of-semantic-shift-in-longitudinal-monitoring-of-social-media/ X-COST-TYPE:free X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nAbstr act
\nSocial media allows researchers to track societal and cultural changes over time based on language analysis tools. Many of thes e tools rely on statistical algorithms which need to be tuned to specific types of language. Recent studies have shown the absence of appropriate tu ning\, specifically in the presence of semantic shift\, can hinder robustn ess of the underlying methods. However\, little is known about the practic al effect this sensitivity may have on downstream longitudinal analyses. W e explore this gap in the literature through a timely case study: understa nding shifts in depression during the course of the COVID-19 pandemic. We find that inclusion of only a small number of semantically-unstable featur es can promote significant changes in longitudinal estimates of our target outcome. At the same time\, we demonstrate that a recently-introduced met hod for measuring semantic shift may be used to proactively identify failu re points of language-based models and\, in turn\, improve predictive gene ralization.
\n X-TAGS;LANGUAGE=en-US:2022\,Harrigian\,March END:VEVENT BEGIN:VEVENT UID:ai1ec-24457@www.clsp.jhu.edu DTSTAMP:20240329T044324Z CATEGORIES;LANGUAGE=en-US:Student Seminars CONTACT: DESCRIPTION:Abstract\nAs artificial intelligence (AI) continues to rapidly expand into existing healthcare infrastructure – e.g.\, clinical decision support\, administrative tasks\, and public health surveillance – it is pe rhaps more important than ever to reflect on the broader purpose of such s ystems. While much focus has been on the potential for this technology to improve general health outcomes\, there also exists a significant\, but un derstated\, opportunity to use this technology to address health-related d isparities. Accomplishing the latter depends not only on our ability to ef fectively identify addressable areas of systemic inequality and translate them into tasks that are machine learnable\, but also our ability to measu re\, interpret\, and counteract barriers in training data that may inhibit robustness to distribution shift upon deployment (i.e.\, new populations\ , temporal dynamics). In this talk\, we will discuss progress made along b oth of these dimensions. We will begin by providing background on the stat e of AI for promoting health equity. Then\, we will present results from a recent clinical phenotyping project and discuss their implication on prev ailing views regarding language model robustness in clinical applications. Finally\, we will showcase ongoing efforts to proactively address systemi c inequality in healthcare by identifying and characterizing stigmatizing language in medical records. DTSTART;TZID=America/New_York:20240226T120000 DTEND;TZID=America/New_York:20240226T131500 LOCATION:Hackerman Hall B17 @ 3400 N. Charles Street\, Baltimore\, MD 21218 SEQUENCE:0 SUMMARY:Keith Harrigian (JHU) “Fighting Bias From Bias: Robust Natural Lang uage Processing Techniques to Promote Health Equity” URL:https://www.clsp.jhu.edu/events/keith-harrigian-jhu-fighting-bias-from- bias-robust-natural-language-processing-techniques-to-promote-health-equit y/ X-COST-TYPE:free X-ALT-DESC;FMTTYPE=text/html:\\n\\n\\nAbstr act
\nAs artificial intelligence (AI) continues to rapidly expand into existing healthcare infrastructure – e.g.\, clinical decision support\, administrative tasks\, and public health surveillance – it is pe rhaps more important than ever to reflect on the broader purpose of such s ystems. While much focus has been on the potential for this technology to improve general health outcomes\, there also exists a significant\, but un derstated\, opportunity to use this technology to address health-related d isparities. Accomplishing the latter depends not only on our ability to ef fectively identify addressable areas of systemic inequality and translate them into tasks that are machine learnable\, but also our ability to measu re\, interpret\, and counteract barriers in training data that may inhibit robustness to distribution shift upon deployment (i.e.\, new populations\ , temporal dynamics). In this talk\, we will discuss progress made along b oth of these dimensions. We will begin by providing background on the stat e of AI for promoting health equity. Then\, we will present results from a recent clinical phenotyping project and discuss their implication on prev ailing views regarding language model robustness in clinical applications. Finally\, we will showcase ongoing efforts to proactively address systemi c inequality in healthcare by identifying and characterizing stigmatizing language in medical records.
\n X-TAGS;LANGUAGE=en-US:2024\,February\,Harrigian END:VEVENT BEGIN:VEVENT UID:ai1ec-24511@www.clsp.jhu.edu DTSTAMP:20240329T044324Z CATEGORIES;LANGUAGE=en-US:Student Seminars CONTACT: DESCRIPTION: DTSTART;TZID=America/New_York:20240412T120000 DTEND;TZID=America/New_York:20240412T131500 LOCATION:Hackerman Hall B17 @ 3400 N. Charles Street\, Baltimore\, MD 21218 SEQUENCE:0 SUMMARY:Sonal Joshi (JHU) URL:https://www.clsp.jhu.edu/events/sonal-joshi-jhu/ X-COST-TYPE:free X-TAGS;LANGUAGE=en-US:2024\,April\,Joshi END:VEVENT END:VCALENDAR