Interactive dense pixel visualizations for time series and model attribution explanations
Udo Schlegel, Daniel A. Keim
TL;DR
The paper tackles interpretability in time-series XAI by introducing DAVOTS, a dense-pixel visualization that places raw time series, neural activations, and attributions in a single row augmented with histograms. It leverages hierarchical clustering with multiple distance metrics to order samples, enabling pattern discovery across large datasets. Demonstrated on a CNN trained on the FordA dataset, DAVOTS reveals how different data types reveal complementary patterns and how clustering choice affects pattern visibility. The work outlines concrete future directions to enhance interactivity and clustering methods for deeper model understanding in time-series contexts.
Abstract
The field of Explainable Artificial Intelligence (XAI) for Deep Neural Network models has developed significantly, offering numerous techniques to extract explanations from models. However, evaluating explanations is often not trivial, and differences in applied metrics can be subtle, especially with non-intelligible data. Thus, there is a need for visualizations tailored to explore explanations for domains with such data, e.g., time series. We propose DAVOTS, an interactive visual analytics approach to explore raw time series data, activations of neural networks, and attributions in a dense-pixel visualization to gain insights into the data, models' decisions, and explanations. To further support users in exploring large datasets, we apply clustering approaches to the visualized data domains to highlight groups and present ordering strategies for individual and combined data exploration to facilitate finding patterns. We visualize a CNN trained on the FordA dataset to demonstrate the approach.
