Abstract Sensitivity analysis is a popular feature selection approach employed to identify the important features in a dataset. In sensitivity analysis, each input feature is perturbed one-at-a-time and the response of the machine learning model is examined to determine the feature's rank. Note that the existing perturbation techniques may lead to inaccurate feature ranking due to their sensitivity to perturbation parameters. This study proposes a novel approach that involves the perturbation of input features using a complex-step. The implementation of complex-step perturbation in the framework of deep neural networks as a feature selection method is provided in this paper, and its efficacy in determining important features for real-world datasets is demonstrated. Furthermore, the filter-based feature selection methods are employed, and the results obtained from the proposed method are compared. While the results obtained for the classification task indicated that the proposed method outperformed other feature ranking methods, in the case of the regression task, it was found to perform more or less similar to that of other feature ranking methods.
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Validation, Robustness, and Accuracy of Perturbation-Based Sensitivity Analysis Methods for Time-Series Deep Learning Models
This work undertakes studies to evaluate Interpretability Methods for Time Series Deep Learning. Sensitivity analysis assesses how input changes affect the output, constituting a key component of interpretation. Among the post-hoc interpretation methods such as back-propagation, perturbation, and approximation, my work will investigate perturbation-based sensitivity Analysis methods on modern Transformer models to benchmark their performances. Specifically, my work intends to answer three research questions: 1) Do different sensitivity analysis methods yield comparable outputs and attribute importance rankings? 2) Using the same sensitivity analysis method, do different Deep Learning models impact the output of the sensitivity analysis? 3) How well do the results from sensitivity analysis methods align with the ground truth?
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- Award ID(s):
- 2151597
- PAR ID:
- 10583572
- Editor(s):
- Michael, Wooldridge; Dy, Jennifer; Natarajan, Sriraam
- Publisher / Repository:
- ACM Digital Library
- Date Published:
- Journal Name:
- Proceedings of the AAAI Conference on Artificial Intelligence
- Edition / Version:
- 1
- Volume:
- 38
- Issue:
- 21
- ISSN:
- 2159-5399
- Page Range / eLocation ID:
- 23768 to 23770
- Subject(s) / Keyword(s):
- perturbation sensitivity analysis time-series deep learning
- Format(s):
- Medium: X Size: 67 KB Other: pdf
- Size(s):
- 67 KB
- Sponsoring Org:
- National Science Foundation
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