SiBBlInGS: Similarity-driven Building-Block Inference using Graphs across States
This addresses the need for interpretable analysis of multi-state time series in scientific domains, offering a method that improves over existing approaches by better modeling real-world data complexities, though it appears incremental as an enhancement to dictionary learning techniques.
The paper tackles the problem of identifying interpretable building blocks in time series data across distinct states, presenting SiBBlInGS, a graph-based dictionary learning framework that captures inter- and intra-state variability, handles missing samples and variable session durations, and demonstrates robustness in synthetic and real-world examples like web search and neural data.
Time series data across scientific domains are often collected under distinct states (e.g., tasks), wherein latent processes (e.g., biological factors) create complex inter- and intra-state variability. A key approach to capture this complexity is to uncover fundamental interpretable units within the data, Building Blocks (BBs), which modulate their activity and adjust their structure across observations. Existing methods for identifying BBs in multi-way data often overlook inter- vs. intra-state variability, produce uninterpretable components, or do not align with properties of real-world data, such as missing samples and sessions of different duration. Here, we present a framework for Similarity-driven Building Block Inference using Graphs across States (SiBBlInGS). SiBBlInGS offers a graph-based dictionary learning approach for discovering sparse BBs along with their temporal traces, based on co-activity patterns and inter- vs. intra-state relationships. Moreover, SiBBlInGS captures per-trial temporal variability and controlled cross-state structural BB adaptations, identifies state-specific vs. state-invariant components, and accommodates variability in the number and duration of observed sessions across states. We demonstrate SiBBlInGS's ability to reveal insights into complex phenomena as well as its robustness to noise and missing samples through several synthetic and real-world examples, including web search and neural data.