Search Results for author: Ophir Frieder

Found 20 papers, 7 papers with code

TBD3: A Thresholding-Based Dynamic Depression Detection from Social Media for Low-Resource Users

1 code implementation LREC 2022 Hrishikesh Kulkarni, Sean MacAvaney, Nazli Goharian, Ophir Frieder

To complement this evaluation, we propose a dynamic thresholding technique that adjusts the classifier’s sensitivity as a function of the number of posts a user has.

Depression Detection

Lexically-Accelerated Dense Retrieval

no code implementations31 Jul 2023 Hrishikesh Kulkarni, Sean MacAvaney, Nazli Goharian, Ophir Frieder

We introduce 'LADR' (Lexically-Accelerated Dense Retrieval), a simple-yet-effective approach that improves the efficiency of existing dense retrieval models without compromising on retrieval effectiveness.

Retrieval

Caching Historical Embeddings in Conversational Search

no code implementations25 Nov 2022 Ophir Frieder, Ida Mele, Cristina Ioana Muntean, Franco Maria Nardini, Raffaele Perego, Nicola Tonellotto

Our achieved high cache hit rates significantly improve the responsiveness of conversational systems while likewise reducing the number of queries managed on the search back-end.

Conversational Search Document Embedding +1

Self-supervised Representation Learning on Electronic Health Records with Graph Kernel Infomax

no code implementations1 Sep 2022 Hao-Ren Yao, Nairen Cao, Katina Russell, Der-Chen Chang, Ophir Frieder, Jeremy Fineman

We propose Graph Kernel Infomax, a self-supervised graph kernel learning approach on the graphical representation of EHR, to overcome the previous problems.

Contrastive Learning Data Augmentation +1

TAR on Social Media: A Framework for Online Content Moderation

1 code implementation29 Aug 2021 Eugene Yang, David D. Lewis, Ophir Frieder

Content moderation (removing or limiting the distribution of posts based on their contents) is one tool social networks use to fight problems such as harassment and disinformation.

Active Learning Retrieval +1

Certifying One-Phase Technology-Assisted Reviews

no code implementations29 Aug 2021 David D. Lewis, Eugene Yang, Ophir Frieder

Technology-assisted review (TAR) workflows based on iterative active learning are widely used in document review applications.

Active Learning TAR +1

On Minimizing Cost in Legal Document Review Workflows

1 code implementation18 Jun 2021 Eugene Yang, David D. Lewis, Ophir Frieder

Technology-assisted review (TAR) refers to human-in-the-loop machine learning workflows for document review in legal discovery and other high recall review tasks.

Active Learning TAR

Heuristic Stopping Rules For Technology-Assisted Review

no code implementations18 Jun 2021 Eugene Yang, David D. Lewis, Ophir Frieder

Technology-assisted review (TAR) refers to human-in-the-loop active learning workflows for finding relevant documents in large collections.

Active Learning TAR

Goldilocks: Just-Right Tuning of BERT for Technology-Assisted Review

no code implementations3 May 2021 Eugene Yang, Sean MacAvaney, David D. Lewis, Ophir Frieder

We indeed find that the pre-trained BERT model reduces review cost by 10% to 15% in TAR workflows simulated on the RCV1-v2 newswire collection.

Active Learning Language Modelling +4

The Analysis from Nonlinear Distance Metric to Kernel-based Drug Prescription Prediction System

no code implementations4 Feb 2021 Der-Chen Chang, Ophir Frieder, Chi-Feng Hung, Hao-Ren Yao

Distance metrics and their nonlinear variant play a crucial role in machine learning based real-world problem solving.

Cross-Global Attention Graph Kernel Network Prediction of Drug Prescription

no code implementations4 Aug 2020 Hao-Ren Yao, Der-Chen Chang, Ophir Frieder, Wendy Huang, I-Chia Liang, Chi-Feng Hung

We present an end-to-end, interpretable, deep-learning architecture to learn a graph kernel that predicts the outcome of chronic disease drug prescription.

Graph Classification Metric Learning

Interaction Matching for Long-Tail Multi-Label Classification

no code implementations18 May 2020 Sean MacAvaney, Franck Dernoncourt, Walter Chang, Nazli Goharian, Ophir Frieder

We present an elegant and effective approach for addressing limitations in existing multi-label classification models by incorporating interaction matching, a concept shown to be useful for ad-hoc search result ranking.

Classification General Classification +1

Training Curricula for Open Domain Answer Re-Ranking

1 code implementation29 Apr 2020 Sean MacAvaney, Franco Maria Nardini, Raffaele Perego, Nicola Tonellotto, Nazli Goharian, Ophir Frieder

We show that the proposed heuristics can be used to build a training curriculum that down-weights difficult samples early in the training process.

Re-Ranking

Expansion via Prediction of Importance with Contextualization

1 code implementation29 Apr 2020 Sean MacAvaney, Franco Maria Nardini, Raffaele Perego, Nicola Tonellotto, Nazli Goharian, Ophir Frieder

We also observe that the performance is additive with the current leading first-stage retrieval methods, further narrowing the gap between inexpensive and cost-prohibitive passage ranking approaches.

Language Modelling Passage Ranking +2

Topical Result Caching in Web Search Engines

no code implementations9 Jan 2020 Ida Mele, Nicola Tonellotto, Ophir Frieder, Raffaele Perego

The results of queries characterized by a topic are kept in the fraction of the cache dedicated to it.

Information Retrieval Retrieval

Content-Based Weak Supervision for Ad-Hoc Re-Ranking

1 code implementation1 Jul 2017 Sean MacAvaney, Andrew Yates, Kai Hui, Ophir Frieder

One challenge with neural ranking is the need for a large amount of manually-labeled relevance judgments for training.

Information Retrieval Re-Ranking

Effects of Sampling on Twitter Trend Detection

no code implementations LREC 2016 Andrew Yates, Alek Kolcz, Nazli Goharian, Ophir Frieder

In this work we use a larger feed to investigate the effects of sampling on Twitter trend detection.

A Framework for Public Health Surveillance

no code implementations LREC 2014 Andrew Yates, Jon Parker, Nazli Goharian, Ophir Frieder

With the rapid growth of social media, there is increasing potential to augment traditional public health surveillance methods with data from social media.

Information Retrieval

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