4 papers
Nondiagonal Mixture of Dirichlet Network Distributions for Analyzing a Stock Ownership Network
Wenning Zhang, Ryohei Hisano, Takaaki Ohnishi +1
Block modeling is widely used in studies on complex networks. The cornerstone model is the stochastic block model (SBM), widely used over the past decades. However, the SBM is limi…
Identifying the Hierarchical Influence Structure Behind Smart Sanctions Using Network Analysis
Ryohei Hisano, Hiroshi Iyetomi, Takayuki Mizuno
Smart sanctions are an increasingly popular tool in foreign policy. Countries and international institutions worldwide issue such lists to sanction targeted entities through financ…
Prediction of ESG Compliance using a Heterogeneous Information Network
Ryohei Hisano, Didier Sornette, Takayuki Mizuno
Negative screening is one method to avoid interactions with inappropriate entities. For example, financial institutions keep investment exclusion lists of inappropriate firms that…
Learning Topic Models by Neighborhood Aggregation
Ryohei Hisano
Topic models are frequently used in machine learning owing to their high interpretability and modular structure. However, extending a topic model to include a supervisory signal, t…