GECOBench: A Gender-Controlled Text Dataset and Benchmark for Quantifying Biases in Explanations
This addresses the issue of quantifying biases in AI explanations for researchers and practitioners in NLP, though it is incremental as it builds on existing XAI methods and bias studies.
The authors tackled the problem of gender bias in feature attributions from explainable AI (XAI) techniques by creating GECOBench, a gender-controlled dataset and benchmark, and found that fine-tuning embedding layers significantly improves explanation performance, with clear dependencies on the number of fine-tuned layers.
Large pre-trained language models have become a crucial backbone for many downstream tasks in natural language processing (NLP), and while they are trained on a plethora of data containing a variety of biases, such as gender biases, it has been shown that they can also inherit such biases in their weights, potentially affecting their prediction behavior. However, it is unclear to what extent these biases also affect feature attributions generated by applying "explainable artificial intelligence" (XAI) techniques, possibly in unfavorable ways. To systematically study this question, we create a gender-controlled text dataset, GECO, in which the alteration of grammatical gender forms induces class-specific words and provides ground truth feature attributions for gender classification tasks. This enables an objective evaluation of the correctness of XAI methods. We apply this dataset to the pre-trained BERT model, which we fine-tune to different degrees, to quantitatively measure how pre-training induces undesirable bias in feature attributions and to what extent fine-tuning can mitigate such explanation bias. To this extent, we provide GECOBench, a rigorous quantitative evaluation framework for benchmarking popular XAI methods. We show a clear dependency between explanation performance and the number of fine-tuned layers, where XAI methods are observed to benefit particularly from fine-tuning or complete retraining of embedding layers.