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 Personal Assistant Systems


FedRKG: A Privacy-preserving Federated Recommendation Framework via Knowledge Graph Enhancement

arXiv.org Artificial Intelligence

Federated Learning (FL) has emerged as a promising approach for preserving data privacy in recommendation systems by training models locally. Recently, Graph Neural Networks (GNN) have gained popularity in recommendation tasks due to their ability to capture high-order interactions between users and items. However, privacy concerns prevent the global sharing of the entire user-item graph. To address this limitation, some methods create pseudo-interacted items or users in the graph to compensate for missing information for each client. Unfortunately, these methods introduce random noise and raise privacy concerns. In this paper, we propose FedRKG, a novel federated recommendation system, where a global knowledge graph (KG) is constructed and maintained on the server using publicly available item information, enabling higher-order user-item interactions. On the client side, a relation-aware GNN model leverages diverse KG relationships. To protect local interaction items and obscure gradients, we employ pseudo-labeling and Local Differential Privacy (LDP). Extensive experiments conducted on three real-world datasets demonstrate the competitive performance of our approach compared to centralized algorithms while ensuring privacy preservation. Moreover, FedRKG achieves an average accuracy improvement of 4% compared to existing federated learning baselines.


Beyond RMSE and MAE: Introducing EAUC to unmask hidden bias and unfairness in dyadic regression models

arXiv.org Artificial Intelligence

This research paper delves into three interrelated aspects: regression over dyadic data, the evaluation of such tasks, and the pervasive issue of unfairness biases in AI. Dyadic data systems play a significant role in our data-driven world, being at the core of recommendation engines, personalized content delivery, and countless applications which involve understanding complex relationships between entities like products, movies, or even potential job candidates. In these contexts, regression over dyadic data becomes the process of predicting values for a given pair of entities, such as user ratings for specific products or evaluating the suitability of a job applicant. These predictions can influence anything, from purchasing decisions to employment opportunities. However, within these critical tasks, the presence of biases related to unfairness can have profound implications, such as disparate impacts on minority or vulnerable groups, unequal access to opportunities, and discriminatory decision-making processes [1] [2]. From a legal perspective, regulations and guidelines are emerging globally to ensure fairness and ethics in AI systems. For instance, the European Union's AI Act will regulate that AI systems must


Matching of Users and Creators in Two-Sided Markets with Departures

arXiv.org Artificial Intelligence

Many online platforms of today, including social media sites, are two-sided markets bridging content creators and users. Most of the existing literature on platform recommendation algorithms largely focuses on user preferences and decisions, and does not simultaneously address creator incentives. We propose a model of content recommendation that explicitly focuses on the dynamics of user-content matching, with the novel property that both users and creators may leave the platform permanently if they do not experience sufficient engagement. In our model, each player decides to participate at each time step based on utilities derived from the current match: users based on alignment of the recommended content with their preferences, and creators based on their audience size. We show that a user-centric greedy algorithm that does not consider creator departures can result in arbitrarily poor total engagement, relative to an algorithm that maximizes total engagement while accounting for two-sided departures. Moreover, in stark contrast to the case where only users or only creators leave the platform, we prove that with two-sided departures, approximating maximum total engagement within any constant factor is NP-hard. We present two practical algorithms, one with performance guarantees under mild assumptions on user preferences, and another that tends to outperform algorithms that ignore two-sided departures in practice.


SAGE: Smart home Agent with Grounded Execution

arXiv.org Artificial Intelligence

The common sense reasoning abilities and vast general knowledge of Large Language Models (LLMs) make them a natural fit for interpreting user requests in a Smart Home assistant context. LLMs, however, lack specific knowledge about the user and their home limit their potential impact. SAGE (Smart Home Agent with Grounded Execution), overcomes these and other limitations by using a scheme in which a user request triggers an LLM-controlled sequence of discrete actions. These actions can be used to retrieve information, interact with the user, or manipulate device states. SAGE controls this process through a dynamically constructed tree of LLM prompts, which help it decide which action to take next, whether an action was successful, and when to terminate the process. The SAGE action set augments an LLM's capabilities to support some of the most critical requirements for a Smart Home assistant. These include: flexible and scalable user preference management ("is my team playing tonight?"), access to any smart device's full functionality without device-specific code via API reading "turn down the screen brightness on my dryer", persistent device state monitoring ("remind me to throw out the milk when I open the fridge"), natural device references using only a photo of the room ("turn on the light on the dresser"), and more. We introduce a benchmark of 50 new and challenging smart home tasks where SAGE achieves a 75% success rate, significantly outperforming existing LLM-enabled baselines (30% success rate).


The loves and lives ruined by the Ashley Madison dating site hack

The Guardian

If you listened to Stephen Fry's recent podcast, it might have left you puzzled. The recording of MS Singh's The Missing Lines cut off after just two minutes and 48 seconds – leaving the next nine chapters in silence. But this was no mistake; it was a trick to raise awareness for the people who go missing every 90 seconds. This isn't the first time a podcast has been used as a stunt. Joe Lycett recently announced Turdcast – a podcast in which celebrities talk about their poo, such as Gary Lineker and his great pitch poo at the 1990 World Cup.


Enhancing Scalability in Recommender Systems through Lottery Ticket Hypothesis and Knowledge Distillation-based Neural Network Pruning

arXiv.org Artificial Intelligence

This study introduces an innovative approach aimed at the efficient pruning of neural networks, with a particular focus on their deployment on edge devices. Our method involves the integration of the Lottery Ticket Hypothesis (LTH) with the Knowledge Distillation (KD) framework, resulting in the formulation of three distinct pruning models. These models have been developed to address scalability issue in recommender systems, whereby the complexities of deep learning models have hindered their practical deployment. With judicious application of the pruning techniques, we effectively curtail the power consumption and model dimensions without compromising on accuracy. Empirical evaluation has been performed using two real world datasets from diverse domains against two baselines. Gratifyingly, our approaches yielded a GPU computation-power reduction of up to 66.67%. Notably, our study contributes to the field of recommendation system by pioneering the application of LTH and KD.


Improving One-class Recommendation with Multi-tasking on Various Preference Intensities

arXiv.org Artificial Intelligence

In general, implicit feedback is easier to obtain than explicit feedback. Thus, making recommendations with only implicit feedback is indispensable. This type of problems are referred to as one-class recommendation [6]. There are several efforts proposed to solve one-class recommendation problems. For example, model-based methods [2, 7] aim to learn a vector representation for each user and item and apply some kernel, such as inner product for matrix factorization (MF) [5], to measure similarity. On the other hand, graph-based methods [11] construct a user-item bipartite graph from historical interactions and utilize random walk on it to explore user interests and make recommendations. In recent years, hybrid approaches [4, 10] combining model-based and graph-based methods have been developed. They explore high-order relationships on the bipartite graph and encode this information into learned entity representations, resulting in remarkable improvements in one-class recommendation tasks. Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page.


Clickbait vs. Quality: How Engagement-Based Optimization Shapes the Content Landscape in Online Platforms

arXiv.org Artificial Intelligence

Online content platforms commonly use engagement-based optimization when making recommendations. This encourages content creators to invest in quality, but also rewards gaming tricks such as clickbait. To understand the total impact on the content landscape, we study a game between content creators competing on the basis of engagement metrics and analyze the equilibrium decisions about investment in quality and gaming. First, we show the content created at equilibrium exhibits a positive correlation between quality and gaming, and we empirically validate this finding on a Twitter dataset. Using the equilibrium structure of the content landscape, we then examine the downstream performance of engagement-based optimization along several axes. Perhaps counterintuitively, the average quality of content consumed by users can decrease at equilibrium as gaming tricks become more costly for content creators to employ. Moreover, engagement-based optimization can perform worse in terms of user utility than a baseline with random recommendations, and engagement-based optimization is also suboptimal in terms of realized engagement relative to quality-based optimization. Altogether, our results highlight the need to consider content creator incentives when evaluating a platform's choice of optimization metric.


Leveraging Negative Signals with Self-Attention for Sequential Music Recommendation

arXiv.org Artificial Intelligence

Music streaming services heavily rely on their recommendation engines to continuously provide content to their consumers. Sequential recommendation consequently has seen considerable attention in current literature, where state of the art approaches focus on self-attentive models leveraging contextual information such as long and short-term user history and item features; however, most of these studies focus on long-form content domains (retail, movie, etc.) rather than short-form, such as music. Additionally, many do not explore incorporating negative session-level feedback during training. In this study, we investigate the use of transformer-based self-attentive architectures to learn implicit session-level information for sequential music recommendation. We additionally propose a contrastive learning task to incorporate negative feedback (e.g skipped tracks) to promote positive hits and penalize negative hits. This task is formulated as a simple loss term that can be incorporated into a variety of deep learning architectures for sequential recommendation. Our experiments show that this results in consistent performance gains over the baseline architectures ignoring negative user feedback.


Chat Failures and Troubles: Reasons and Solutions

arXiv.org Artificial Intelligence

This paper examines some common problems in Human-Robot Interaction (HRI) causing failures and troubles in Chat. A given use case's design decisions start with the suitable robot, the suitable chatting model, identifying common problems that cause failures, identifying potential solutions, and planning continuous improvement. In conclusion, it is recommended to use a closed-loop control algorithm that guides the use of trained Artificial Intelligence (AI) pre-trained models and provides vocabulary filtering, re-train batched models on new datasets, learn online from data streams, and/or use reinforcement learning models to self-update the trained models and reduce errors.