Key research themes
1. How can structural balance theory be extended to directed signed social networks to better model real-world communications?
Structural balance theory traditionally applies to undirected social networks, assuming triads tend toward stable configurations with positive or negative edges. However, many real-world social and communication networks have directed edges with sign (positive or negative), reflecting asymmetric relations such as trust or sentiment. Extending structural balance theory to signed digraphs allows simultaneous consideration of transitivity and sign consistency in triads, improving the modeling of communication dynamics and organizational interactions. This research theme focuses on developing metrics and empirical analyses to validate balance in signed directed social networks.
2. What computational methods can be developed for community detection and friend recommendation in signed social networks that account for the duality of positive and negative ties?
Community detection in signed social networks is complicated by the presence of both positive (friendly, trust) and negative (hostile, distrust) edges. Effective clustering requires objective functions that simultaneously maximize positive intra-community ties and negative inter-community ties to capture real-world social structures. Moreover, for directed signed networks, friend recommendation systems need to consider not only link sign but also directionality and node status. This research theme explores multi-objective optimization algorithms, genetic algorithms, and status theory to uncover overlapping community structures and generate meaningful friend recommendations, thus reflecting the nuanced nature of signed social relations.
3. How can influence maximization and information diffusion in signed social networks be modeled considering trust and distrust links?
Information diffusion and viral influence in social networks are critical for marketing, opinion formation, and rumor dynamics. Traditional influence maximization models typically consider only positive (trust) relationships. However, signed social networks include both trust and distrust links, whose interplay significantly affects diffusion. This research theme investigates models that incorporate distrust propagation schemes alongside trust, characterizes the non-monotonicity and NP-hardness of maximizing influence in such settings, and proposes algorithms to more accurately predict influence spread. The work seeks to better represent real-world influence phenomena by integrating antagonistic social relations into diffusion frameworks.
4. What methods improve prediction of negative links and privacy-preserving anonymization in signed social networks?
Negative links in signed social networks—representing distrust, hostility, or dislike—are challenging to predict due to their rarity, asymmetric propagation, and complexity. Accurate negative sign prediction enhances applications such as recommender systems and trust evaluation. Concurrently, anonymizing signed social network graphs while preserving graph utility and controlling information loss is crucial for privacy. This research theme explores feature-based models integrating diverse negative-sign-related indicators to improve prediction accuracy, and proposes algorithms to optimally determine anonymization levels (k-degree anonymity) tailored to graph structural properties, balancing privacy and data utility.