Antonio Anastasio Bruto da Costa

Priyanka Sinha, Pabitra Mitra, Antonio Anastasio Bruto da Costa et al.

Multi-party dialogues are common in enterprise social media on technical as well as non-technical topics. The outcome of a conversation may be positive or negative. It is important to analyze why a dialogue ends with a particular sentiment from the point of view of conflict analysis as well as future collaboration design. We propose an explainable time series mining algorithm for such analysis. A dialogue is represented as an attributed time series of occurrences of keywords, EMPATH categories, and inferred sentiments at various points in its progress. A special decision tree, with decision metrics that take into account temporal relationships between dialogue events, is used for predicting the cause of the outcome sentiment. Interpretable rules mined from the classifier are used to explain the prediction. Experimental results are presented for the enterprise social media posts in a large company.

Antonio Anastasio Bruto da Costa, Pallab Dasgupta

We aim to mine temporal causal sequences that explain observed events (consequents) in time-series traces. Causal explanations of key events in a time-series has applications in design debugging, anomaly detection, planning, root-cause analysis and many more. We make use of decision trees and interval arithmetic to mine sequences that explain defining events in the time-series. We propose modified decision tree construction metrics to handle the non-determinism introduced by the temporal dimension. The mined sequences are expressed in a readable temporal logic language that is easy to interpret. The application of the proposed methodology is illustrated through various examples.

Antonio Anastasio Bruto da Costa, Goran Frehse, Pallab Dasgupta

In current practice a formal analysis of hybrid system models is assertion-based. The work presented here is based on features that look beyond functional correctness toward a quantitative evaluation of behavioral attributes. A feature defines a real-valued evaluation function over a specific set of traces. This paper describes an improved method for the interpretation of features over hybrid automata models. It further demonstrates how satisfiability modulo theory solvers can be used for extracting behavioral traces corresponding to corner cases of a feature. Results are demonstrated on examples from the control and circuit domains.