Enhancing Plausibility of Text Classifier Explanations Using Human Rationales

Core Concepts

Incorporating human-annotated rationales into text classification models enhances the plausibility of post-hoc explanations without substantially degrading model performance.

Abstract

The paper presents a methodology for incorporating human rationales, which are text annotations explaining human decisions, into text classification models. This approach aims to enhance the plausibility of post-hoc explanations while preserving their faithfulness. The key highlights are: The authors introduce a novel contrastive-inspired loss function that effectively integrates rationales into the model training process. This loss function does not require modifying the model architecture or assuming a specific type of explanation function. The authors employ a multi-objective optimization framework to explore the trade-off between model performance and explanation plausibility. This allows them to generate a Pareto-optimal frontier of models that balance these two objectives. Through extensive experiments involving diverse models, datasets, and explainability methods, the authors demonstrate that their approach significantly enhances the quality of model explanations without causing substantial (sometimes negligible) degradation in the original model's performance. The authors compare their methodology with a previous method from the literature, reinforcing the effectiveness of their approach in improving explanation plausibility while maintaining faithfulness. The authors discuss the social and ethical implications of "teaching" explanations to text classification models, arguing that these concerns are mitigated when the explanations remain faithful to the model's decision-making process.

Stats

"This is such a great movie !" "ugh i hate d*kes"

Quotes

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Key Insights Distilled From

Exploring the Trade-off Between Model Performance and Explanation Plausibility of Text Classifiers Using Human Rationales

by Lucas E. Res... at arxiv.org 04-05-2024

https://arxiv.org/pdf/2404.03098.pdf

Deeper Inquiries

How can the proposed methodology be extended to handle longer text inputs, such as documents, without compromising performance and explanation quality?

To extend the proposed methodology to handle longer text inputs, such as documents, without compromising performance and explanation quality, several strategies can be implemented: Chunking and Aggregation: Divide the longer text inputs into smaller chunks or segments and process them individually. After obtaining explanations for each segment, aggregate the results to provide an overall explanation for the entire document. This approach ensures that the model can handle longer texts while maintaining explanation quality. Hierarchical Models: Implement hierarchical models that can process text at different levels of granularity. For instance, a model could first analyze the document at the paragraph level, then at the sentence level, and finally at the word level. This hierarchical approach allows for a more detailed analysis of longer texts. Attention Mechanisms: Utilize attention mechanisms that focus on relevant parts of the text at different levels of abstraction. By incorporating attention mechanisms, the model can effectively capture the most important information in longer documents while providing interpretable explanations for its decisions. Memory-Augmented Networks: Implement memory-augmented networks that can store and retrieve relevant information from longer texts. These networks can maintain context across the document and improve the model's understanding of the text, leading to more accurate explanations. Data Augmentation: Augment the training data with longer text samples to improve the model's ability to handle such inputs. By exposing the model to a diverse range of text lengths during training, it can learn to process longer texts more effectively. By incorporating these strategies, the proposed methodology can be extended to handle longer text inputs, such as documents, while preserving performance and explanation quality.

How can the potential limitations of relying on human-annotated rationales be addressed, and how can the methodology be adapted to handle cases where such annotations are not available?

Addressing the potential limitations of relying on human-annotated rationales and adapting the methodology for cases where such annotations are not available can be achieved through the following approaches: Weak Supervision: Implement weak supervision techniques, such as distant supervision or self-training, to generate pseudo-annotations for training the model in the absence of human-annotated rationales. These methods leverage existing knowledge sources or model predictions to provide supervision signals. Unsupervised Learning: Explore unsupervised learning approaches, such as clustering or autoencoders, to learn representations from the text data itself without the need for human annotations. By extracting meaningful patterns and structures from the data, the model can still generate explanations without explicit human guidance. Semi-Supervised Learning: Combine a small amount of human-annotated rationales with a larger set of unlabeled data to train the model in a semi-supervised manner. This approach leverages the available annotations while maximizing the utilization of unlabeled data for learning. Transfer Learning: Utilize transfer learning techniques to adapt pre-trained models to new tasks or domains where human-annotated rationales are scarce. By fine-tuning models on related tasks with available annotations, the model can generalize to tasks with limited supervision. Active Learning: Implement active learning strategies to intelligently select instances for human annotation, focusing on the most informative samples that can improve the model's performance and explanation quality. This iterative process optimizes the use of human resources for annotation. By incorporating these strategies, the methodology can be adapted to handle cases where human-annotated rationales are not available, ensuring robust performance and explanation quality in various scenarios.

How can the insights from this work on enhancing explanation plausibility be applied to other domains beyond text classification, such as image recognition or tabular data analysis?

The insights from enhancing explanation plausibility in text classification can be applied to other domains beyond text, such as image recognition or tabular data analysis, through the following approaches: Interpretable Models: Develop interpretable models for image recognition and tabular data analysis that provide transparent explanations for their predictions. Techniques like attention mechanisms, saliency maps, and feature visualization can enhance explanation plausibility in these domains. Rationale Extraction: Incorporate human-annotated rationales or explanations into the training process of models for image recognition and tabular data analysis. By guiding the model with human insights, the explanations provided by the model can align better with human intuition. Multi-Objective Optimization: Apply multi-objective optimization techniques to balance model performance and explanation plausibility in image recognition and tabular data analysis. By exploring the trade-off between accuracy and interpretability, models can provide more trustworthy explanations. Attention Mechanisms: Utilize attention mechanisms in image recognition to highlight important regions in an image that contribute to the model's decision. In tabular data analysis, attention mechanisms can focus on relevant features or columns that influence the output. Data Augmentation: Augment image datasets with diverse examples and tabular data with varied instances to improve the model's generalization and explanation quality. By exposing the model to a wide range of scenarios during training, it can provide more robust explanations. By applying these insights to image recognition and tabular data analysis, models in these domains can offer more interpretable and trustworthy explanations, enhancing their utility and transparency in real-world applications.