1 code implementation • 8 Aug 2024 • Masoud Mansoury, Bamshad Mobasher, Herke van Hoof
In this paper, we study exposure bias in a class of well-known contextual bandit algorithms known as Linear Cascading Bandits.
1 code implementation • 16 May 2024 • Kun Lin, Masoud Mansoury, Farzad Eskandanian, Milad Sabouri, Bamshad Mobasher
Calibration in recommender systems is an important performance criterion that ensures consistency between the distribution of user preference categories and that of recommendations generated by the system.
no code implementations • 5 Sep 2023 • Masoud Mansoury, Bamshad Mobasher
However, less work has been done on addressing exposure bias in a dynamic recommendation setting where the system is operating over time, the recommendation model and the input data are dynamically updated with ongoing user feedback on recommended items at each round.
no code implementations • 4 Sep 2022 • Masoud Mansoury, Bamshad Mobasher, Herke van Hoof
This is especially problematic when bias is amplified over time as a few items (e. g., popular ones) are repeatedly over-represented in recommendation lists and users' interactions with those items will amplify bias towards those items over time resulting in a feedback loop.
no code implementations • 1 Jul 2022 • Arman Dehpanah, Muheeb Faizan Ghori, Jonathan Gemmell, Bamshad Mobasher
Competitive online games use rating systems for matchmaking; progression-based algorithms that estimate the skill level of players with interpretable ratings in terms of the outcome of the games they played.
no code implementations • 24 May 2022 • Payam Pourashraf, Bamshad Mobasher
With this subscription model, there is a need to increase user engagement and personalization, and recommender systems are one way for these news companies to accomplish this goal.
no code implementations • 29 Nov 2021 • Arman Dehpanah, Muheeb Faizan Ghori, Jonathan Gemmell, Bamshad Mobasher
We then use the created models to predict ranks for different groups of players in the data.
no code implementations • 2 Sep 2021 • Muheeb Faizan Ghori, Arman Dehpanah, Jonathan Gemmell, Hamed Qahri-Saremi, Bamshad Mobasher
Recommender systems have become a ubiquitous part of modern web applications.
no code implementations • 7 Aug 2021 • Masoud Mansoury, Himan Abdollahpouri, Bamshad Mobasher, Mykola Pechenizkiy, Robin Burke, Milad Sabouri
This is especially problematic when bias is amplified over time as a few popular items are repeatedly over-represented in recommendation lists.
no code implementations • 7 Jul 2021 • Masoud Mansoury, Himan Abdollahpouri, Mykola Pechenizkiy, Bamshad Mobasher, Robin Burke
Fairness is a critical system-level objective in recommender systems that has been the subject of extensive recent research.
no code implementations • 21 Jun 2021 • Arman Dehpanah, Muheeb Faizan Ghori, Jonathan Gemmell, Bamshad Mobasher
Rating systems leverage statistical estimation to rate players' skills and use skill ratings to predict rank before matching players.
no code implementations • 28 May 2021 • Arman Dehpanah, Muheeb Faizan Ghori, Jonathan Gemmell, Bamshad Mobasher
It alleviated most of the challenges faced by the other metrics while adding the freedom to adjust the focus of the evaluations on different groups of players.
no code implementations • 11 Mar 2021 • Himan Abdollahpouri, Edward Malthouse, Joseph Konstan, Bamshad Mobasher, Jeremy Gilbert
This paper proposes a vision and research agenda for the next generation of news recommender systems (RS), called the table d'hote approach.
no code implementations • 10 Mar 2021 • Himan Abdollahpouri, Masoud Mansoury, Robin Burke, Bamshad Mobasher, Edward Malthouse
In this paper, we show the limitations of the existing metrics to evaluate popularity bias mitigation when we want to assess these algorithms from the users' perspective and we propose a new metric that can address these limitations.
no code implementations • 21 Aug 2020 • Himan Abdollahpouri, Masoud Mansoury, Robin Burke, Bamshad Mobasher
Moreover, we show that the more a group is affected by the algorithmic popularity bias, the more their recommendations are miscalibrated.
no code implementations • 15 Aug 2020 • Arman Dehpanah, Muheeb Faizan Ghori, Jonathan Gemmell, Bamshad Mobasher
However, less attention has been given to the evaluation metrics of these systems.
no code implementations • 25 Jul 2020 • Masoud Mansoury, Himan Abdollahpouri, Mykola Pechenizkiy, Bamshad Mobasher, Robin Burke
Recommendation algorithms are known to suffer from popularity bias; a few popular items are recommended frequently while the majority of other items are ignored.
no code implementations • 23 Jul 2020 • Himan Abdollahpouri, Masoud Mansoury, Robin Burke, Bamshad Mobasher
The effectiveness of these approaches, however, has not been assessed in multistakeholder environments where in addition to the users who receive the recommendations, the utility of the suppliers of the recommended items should also be considered.
no code implementations • 5 Jun 2020 • Farzad Eskandanian, Bamshad Mobasher
In particular, our results show that the proposed solution is quite effective in increasing aggregate diversity and item-side utility while optimizing recommendation accuracy for end users.
no code implementations • 21 May 2020 • Nasim Sonboli, Farzad Eskandanian, Robin Burke, Weiwen Liu, Bamshad Mobasher
In this paper, we present a re-ranking approach to fairness-aware recommendation that learns individual preferences across multiple fairness dimensions and uses them to enhance provider fairness in recommendation results.
no code implementations • 3 May 2020 • Masoud Mansoury, Himan Abdollahpouri, Mykola Pechenizkiy, Bamshad Mobasher, Robin Burke
That leads to low coverage of items in recommendation lists across users (i. e. low aggregate diversity) and unfair distribution of recommended items.
no code implementations • 18 Feb 2020 • Masoud Mansoury, Himan Abdollahpouri, Jessie Smith, Arman Dehpanah, Mykola Pechenizkiy, Bamshad Mobasher
The proliferation of personalized recommendation technologies has raised concerns about discrepancies in their recommendation performance across different genders, age groups, and racial or ethnic populations.
no code implementations • 13 Oct 2019 • Himan Abdollahpouri, Masoud Mansoury, Robin Burke, Bamshad Mobasher
In this paper, we use a metric called miscalibration for measuring how a recommendation algorithm is responsive to users' true preferences and we consider how various algorithms may result in different degrees of miscalibration.
no code implementations • 13 Sep 2019 • Kun Lin, Nasim Sonboli, Bamshad Mobasher, Robin Burke
Recommender systems are personalized: we expect the results given to a particular user to reflect that user's preferences.
1 code implementation • 2 Aug 2019 • Masoud Mansoury, Bamshad Mobasher, Robin Burke, Mykola Pechenizkiy
Research on fairness in machine learning has been recently extended to recommender systems.
3 code implementations • 31 Jul 2019 • Himan Abdollahpouri, Masoud Mansoury, Robin Burke, Bamshad Mobasher
Recommender systems are known to suffer from the popularity bias problem: popular (i. e. frequently rated) items get a lot of exposure while less popular ones are under-represented in the recommendations.
no code implementations • 10 Jul 2019 • Masoud Mansoury, Robin Burke, Bamshad Mobasher
This transformation flattens the rating distribution, better compensates for differences in rating distributions, and improves recommendation performance.
no code implementations • 14 May 2019 • Farzad Eskandanian, Nasim Sonboli, Bamshad Mobasher
Like other social systems, in collaborative filtering a small number of "influential" users may have a large impact on the recommendations of other users, thus affecting the overall behavior of the system.
no code implementations • 14 May 2019 • Farzad Eskandanian, Bamshad Mobasher
In a variety of online settings involving interaction with end-users it is critical for the systems to adapt to changes in user preferences.
no code implementations • 22 Jan 2019 • Himan Abdollahpouri, Robin Burke, Bamshad Mobasher
Many recommender systems suffer from popularity bias: popular items are recommended frequently while less popular, niche products, are recommended rarely or not at all.
no code implementations • 29 Sep 2018 • Farzad Eskandanian, Bamshad Mobasher
In the second approach the HMM is used directly to generate recommendations taking into account the identified change points.
no code implementations • 15 Feb 2018 • Himan Abdollahpouri, Robin Burke, Bamshad Mobasher
Many recommender systems suffer from the popularity bias problem: popular items are being recommended frequently while less popular, niche products, are recommended rarely if not at all.