35 citations · 90 across the 12 of their papers we have counts for
12 papers
CatalogAgent: A Supervisor-mediated Self-Learning System Enabling Context Engineering for GenAI Models
Zhu Cheng, Zhenming Wang, Yu +14
Product catalogs are the backbone of e-commerce sites, yet a large number of structured attributes (SAs) -- such as material, color, and shape -- often have missing values. Typical…
SAGE: Structured Attribute Value Generation for Billion-Scale Product Catalogs
Athanasios N. Nikolakopoulos, Swati Kaul, Siva Karthik Gade +3
We introduce SAGE; a Generative LLM for inferring attribute values for products across world-wide e-Commerce catalogs. We introduce a novel formulation of the attribute-value predi…
Trust your neighbors: A comprehensive survey of neighborhood-based methods for recommender systems
Athanasios N. Nikolakopoulos, Xia Ning, Christian Desrosiers +1
Collaborative recommendation approaches based on nearest-neighbors are still highly popular today due to their simplicity, their efficiency, and their ability to produce accurate a…
Projection techniques to update the truncated SVD of evolving matrices
Vassilis Kalantzis, Georgios Kollias, Shashanka Ubaru +3
This paper considers the problem of updating the rank-k truncated Singular Value Decomposition (SVD) of matrices subject to the addition of new rows and/or columns over time. Such…
Random Surfing Revisited: Generalizing PageRank's Teleportation Model
Athanasios N. Nikolakopoulos
We revisit the Random Surfer model, focusing on its--often overlooked--Teleportation component, and we introduce NCDawareRank; a novel ranking framework designed to exploit network…
Boosting Item-based Collaborative Filtering via Nearly Uncoupled Random Walks
Athanasios N. Nikolakopoulos, George Karypis
Item-based models are among the most popular collaborative filtering approaches for building recommender systems. Random walks can provide a powerful tool for harvesting the rich n…
Fast Decentralized Optimization over Networks
Meng Ma, Athanasios N. Nikolakopoulos, Georgios B. Giannakis
The present work introduces the hybrid consensus alternating direction method of multipliers (H-CADMM), a novel framework for optimization over networks which unifies existing dist…
Adaptive Diffusions for Scalable Learning over Graphs
Dimitris Berberidis, Athanasios N. Nikolakopoulos, Georgios B. Giannakis
Diffusion-based classifiers such as those relying on the Personalized PageRank and the Heat kernel, enjoy remarkable classification accuracy at modest computational requirements. T…
Kernel-based Inference of Functions over Graphs
Vassilis N. Ioannidis, Meng Ma, Athanasios N. Nikolakopoulos +2
The study of networks has witnessed an explosive growth over the past decades with several ground-breaking methods introduced. A particularly interesting -- and prevalent in severa…
EigenRec: Generalizing PureSVD for Effective and Efficient Top-N Recommendations
Athanasios N. Nikolakopoulos, Vassilis Kalantzis, Efstratios Gallopoulos +1
We introduce EigenRec; a versatile and efficient Latent-Factor framework for Top-N Recommendations that includes the well-known PureSVD algorithm as a special case. EigenRec builds…
Top-N recommendations in the presence of sparsity: An NCD-based approach
Athanasios N. Nikolakopoulos, John D. Garofalakis
Making recommendations in the presence of sparsity is known to present one of the most challenging problems faced by collaborative filtering methods. In this work we tackle this pr…
Random Surfing Without Teleportation
Athanasios N. Nikolakopoulos, John D. Garofalakis
In the standard Random Surfer Model, the teleportation matrix is necessary to ensure that the final PageRank vector is well-defined. The introduction of this matrix, however, resul…