Publications associées à Collaborative Filtering Under a Sybil Attack: Similarity Metrics do Matter!

Optimization Algorithms for Decentralized, Distributed and Collaborative Machine Learning

Distributed learning is the key for enabling training of modern large-scale machine learning models, through parallelising the learning process. Collaborative learning is essential for learning from privacy-sensitive data that is distributed across various ...

EPFL2024

Smaller, Faster & Lighter KNN Graph Constructions

Rachid Guerraoui, Anne-Marie Kermarrec, Olivier Ruas

We propose GoldFinger, a new compact and fast-to-compute binary representation of datasets to approximate Jaccard’s index. We illustrate the effectiveness of GoldFinger on the emblematic big data problem of K-Nearest-Neighbor (KNN) graph construction and s ...

2020

On the Limitations of Cross-lingual Encoders as Exposed by Reference-Free Machine Translation Evaluation

Maxime Jean Julien Peyrard, Robert West, Wei Zhao, Yang Gao

Evaluation of cross-lingual encoders is usually performed either via zero-shot cross-lingual transfer in supervised downstream tasks or via unsupervised cross-lingual textual similarity. In this paper, we concern ourselves with reference-free machine trans ...

ASSOC COMPUTATIONAL LINGUISTICS-ACL2020

Towards a Point Cloud Structural Similarity Metric

Touradj Ebrahimi, Evangelos Alexiou

Point cloud is a 3D image representation that has recently emerged as a viable approach for advanced content modality in modern communication systems. In view of its wide adoption, quality evaluation metrics are essential. In this paper, we propose and ass ...

IEEE2020

Context-based Quality of Experience in Immersive Multimedia

Anne-Flore Nicole Marie Perrin

Since 1895, when the Lumière brothers came out with the projected cinematograph, motion pictures and more generally multimedia contents have considerably improved and are still experiencing a very dynamic development. Advances involved improving various mo ...

EPFL2019

Unified and Scalable Incremental Recommenders with Consumed Item Packs

Rachid Guerraoui, Rhicheek Patra

Recommenders personalize the web content using collaborative filtering to relate users (or items). This work proposes to unify user-based, item-based and neural word embeddings types of recommenders under a single abstraction for their input, we name Consu ...

Springer2019

Towards Scalable Personalization

Rhicheek Patra

The ever-growing amount of online information calls for Personalization. Among the various personalization systems, recommenders have become increasingly popular in recent years. Recommenders typically use collaborative filtering to suggest the most releva ...

EPFL2018

Text Similarity in Vector Space Models: A Comparative Study

Omid Shahmirzadi, Kenneth Younge, Adam Lugowski

Automatic measurement of semantic text similarity is an important task in natural language processing. In this paper, we evaluate the performance of different vector space models to perform this task. We address the real-world problem of modeling patent-to ...

2018

A novel methodology for quality assessment of voxelized point clouds

Touradj Ebrahimi, Evangelos Alexiou

Recent trends in multimedia technologies indicate a significant growth of interest for new imaging modalities that aim to provide immersive experiences by increasing the engagement of the user with the content. Among other solutions, point clouds denote an ...

SPIE-INT SOC OPTICAL ENGINEERING2018

Online Efficient Bio-Medical Video Transcoding on MPSoCs Through Content-Aware Workload Allocation

David Atienza Alonso, Ali Pahlevan, Marina Zapater Sancho, Arman Iranfar

Bio-medical image processing in the field of telemedicine, and in particular the definition of systems that allow medical diagnostics in a collaborative and distributed way is experiencing an undeniable growth. Due to the high quality of bio-medical videos ...

IEEE and ACM Press2018

Capturing the Moment: Lightweight Similarity Computations

Rachid Guerraoui, Rhicheek Patra, Georgios Damaskinos

Similarity computations are crucial in various web activities like advertisements, search or trust-distrust predictions. These similarities often vary with time as product perception and popularity constantly change with users' evolving inclination. The hu ...

IEEE2017

On the performance of metrics to predict quality in point cloud representations

Touradj Ebrahimi, Evangelos Alexiou

Point clouds are a promising alternative for immersive representation of visual contents. Recently, an increased interest has been observed in the acquisition, processing and rendering of this modality. Although subjective and objective evaluations are cri ...

Spie-Int Soc Optical Engineering2017

Recommender Systems for Healthy Behavior Change

Onur Yürüten

Sedentary lifestyles and bad eating habits influence the onset of many serious health problems. Healthy behavior change is an arduous task, and requires a careful planning. In this thesis, we propose that behavior recommenders can help their users achieve ...

EPFL2017

Towards subjective quality assessment of point cloud imaging in augmented reality

Touradj Ebrahimi, Evgeniy Upenik, Evangelos Alexiou

Recently, there has been an increased interest in capture, processing and rendering of visual content in form of point clouds. Among other challenges, subjective and objective quality evaluation of point clouds are still open problems. Most proposed subjec ...

2017

Adaptive relevance feedback for large-scale image retrieval

François Fleuret, Nicolae Suditu

Content-based image retrieval aims at substituting traditional indexing based on manual annotation by using automatically-extracted visual indexing features. Novel techniques are needed however to efficiently deal with the semantic gap (i.e. the partial ma ...

2016

Quality of Experience in Immersive Video Technologies

Philippe Hanhart

Over the last decades, several technological revolutions have impacted the television industry, such as the shifts from black & white to color and from standard to high-definition. Nevertheless, further considerable improvements can still be achieved to pr ...

EPFL2016

Cross-lingual Linking of Multi-word Entities and their corresponding Acronyms

Maud Ehrmann

This paper reports on an approach and experiments to automatically build a cross-lingual multi-word entity resource. Starting from a collection of millions of acronym/expansion pairs for 22 languages where expansion variants were grouped into monolingual c ...

European Language Resources Association (ELRA)2016

A Method for Record Linkage with Sparse Historical Data

Yannick Rochat, Giovanni Colavizza, Maud Ehrmann

Massive digitization of archival material, coupled with automatic document processing techniques and data visualisation tools offers great opportunities for reconstructing and exploring the past. Unprecedented wealth of historical data (e.g. names of perso ...

2016

Subjective and Objective Evaluation of HDR Video Coding Technologies

Touradj Ebrahimi, Philippe Hanhart, Martin Rerabek

This paper reports the details and results of a subjective and objective quality evaluation assessing responses to an MPEG call for evidence (CfE) on high dynamic range (HDR) and wide color gamut video coding. Five HDR video contents, compressed at four bi ...

Ieee2016

Clustering of heterogeneous networks with directional flows based on “Snake” similarities

Nikolaos Geroliminis, Mohammadreza Saeedmanesh

Aggregated network level modeling and control of traffic in urban networks have recently gained a lot of interest due to unpredictability of travel behaviors and high complexity of physical modeling in microscopic level. Recent research has shown the exist ...

Elsevier2016