activity
20172026
most citedCurse of "Low" Dimensionality in Recommender Systems

9 citations · 34 across the 18 of their papers we have counts for

collaborators

18 papers

cs.LG2026

Beyond Match Maximization and Fairness: Retention-Optimized Two-Sided Matching

Ren Kishimoto, Rikiya Takehi, Koichi Tanaka +4

On two-sided matching platforms such as online dating and recruiting, recommendation algorithms often aim to maximize the total number of matches. However, this objective creates a…

cs.CV2025

Instance-wise Supervision-level Optimization in Active Learning

Shinnosuke Matsuo, Riku Togashi, Ryoma Bise +2

Active learning (AL) is a label-efficient machine learning paradigm that focuses on selectively annotating high-value instances to maximize learning efficiency. Its effectiveness c…

cs.CV2024

LTSim: Layout Transportation-based Similarity Measure for Evaluating Layout Generation

Mayu Otani, Naoto Inoue, Kotaro Kikuchi +1

We introduce a layout similarity measure designed to evaluate the results of layout generation. While several similarity measures have been proposed in prior research, there has be…

cs.IR2024★ 4 cited

Scalable and Provably Fair Exposure Control for Large-Scale Recommender Systems

Riku Togashi, Kenshi Abe, Yuta Saito

Typical recommendation and ranking methods aim to optimize the satisfaction of users, but they are often oblivious to their impact on the items (e.g., products, jobs, news, video)…

cs.IR2023

Fast and Examination-agnostic Reciprocal Recommendation in Matching Markets

Yoji Tomita, Riku Togashi, Yuriko Hashizume +1

In matching markets such as job posting and online dating platforms, the recommender system plays a critical role in the success of the platform. Unlike standard recommender system…

cs.IR2023

Safe Collaborative Filtering

Riku Togashi, Tatsushi Oka, Naoto Ohsaka +1

Excellent tail performance is crucial for modern machine learning tasks, such as algorithmic fairness, class imbalance, and risk-sensitive decision making, as it ensures the effect…

cs.IR2023★ 1 cited

A Critical Reexamination of Intra-List Distance and Dispersion

Naoto Ohsaka, Riku Togashi

Diversification of recommendation results is a promising approach for coping with the uncertainty associated with users' information needs. Of particular importance in diversified…

cs.IR2023★ 9 cited

Curse of "Low" Dimensionality in Recommender Systems

Naoto Ohsaka, Riku Togashi

Beyond accuracy, there are a variety of aspects to the quality of recommender systems, such as diversity, fairness, and robustness. We argue that many of the prevalent problems in…

cs.CV2023★ 3 cited

Toward Verifiable and Reproducible Human Evaluation for Text-to-Image Generation

Mayu Otani, Riku Togashi, Yu Sawai +5

Human evaluation is critical for validating the performance of text-to-image generative models, as this highly cognitive process requires deep comprehension of text and images. How…

cs.IR2022★ 3 cited

Fair Matrix Factorisation for Large-Scale Recommender Systems

Riku Togashi, Kenshi Abe

Recommender systems are hedged with various requirements, such as ranking quality, optimisation efficiency, and item fairness. Item fairness is an emerging yet impending issue in p…

cs.MM2022★ 3 cited

DMS: Deep Multi-Modal Sequence Sets with Hierarchical Modality Attention

Shunsuke Kitada, Yuki Iwazaki, Riku Togashi +1

There is increasing interest in the use of multimodal data in various web applications, such as digital advertising and e-commerce. Typical methods for extracting important informa…

cs.IR2022★ 8 cited

Matching Theory-based Recommender Systems in Online Dating

Yoji Tomita, Riku Togashi, Daisuke Moriwaki

Online dating platforms provide people with the opportunity to find a partner. Recommender systems in online dating platforms suggest one side of users to the other side of users.…

cs.CV2022

AxIoU: An Axiomatically Justified Measure for Video Moment Retrieval

Riku Togashi, Mayu Otani, Yuta Nakashima +3

Evaluation measures have a crucial impact on the direction of research. Therefore, it is of utmost importance to develop appropriate and reliable evaluation measures for new applic…

cs.CV2022

Optimal Correction Cost for Object Detection Evaluation

Mayu Otani, Riku Togashi, Yuta Nakashima +3

Mean Average Precision (mAP) is the primary evaluation measure for object detection. Although object detection has a broad range of applications, mAP evaluates detectors in terms o…

cs.LG2021

Scalable Personalised Item Ranking through Parametric Density Estimation

Riku Togashi, Masahiro Kato, Mayu Otani +2

Learning from implicit feedback is challenging because of the difficult nature of the one-class problem: we can observe only positive examples. Most conventional methods use a pair…

cs.IR2021★ 1 cited

Density-Ratio Based Personalised Ranking from Implicit Feedback

Riku Togashi, Masahiro Kato, Mayu Otani +1

Learning from implicit user feedback is challenging as we can only observe positive samples but never access negative ones. Most conventional methods cope with this issue by adopti…

cs.IR2020★ 2 cited

Alleviating Cold-Start Problems in Recommendation through Pseudo-Labelling over Knowledge Graph

Riku Togashi, Mayu Otani, Shin'ichi Satoh

Solving cold-start problems is indispensable to provide meaningful recommendation results for new users and items. Under sparsely observed data, unobserved user-item pairs are also…

cs.IR2017

Relevance Score of Triplets Using Knowledge Graph Embedding - The Pigweed Triple Scorer at WSDM Cup 2017

Vibhor Kanojia, Riku Togashi, Hideyuki Maeda

Collaborative Knowledge Bases such as Freebase and Wikidata mention multiple professions and nationalities for a particular entity. The goal of the WSDM Cup 2017 Triplet Scoring Ch…