An increasing awareness of biased patterns in natural language processing resources, like BERT, has motivated many metrics to quantify `bias' and `fairness'. But comparing the results of different metrics and the works that evaluate with such metrics remains difficult, if not outright impossible. We survey the existing literature on fairness metrics for pretrained language models and experimentally evaluate compatibility, including both biases in language models as in their downstream tasks. We do this by a mixture of traditional literature survey and correlation analysis, as well as by running empirical evaluations. We find that many metrics are not compatible and highly depend on (i) templates, (ii) attribute and target seeds and (iii) the choice of embeddings. These results indicate that fairness or bias evaluation remains challenging for contextualized language models, if not at least highly subjective. To improve future comparisons and fairness evaluations, we recommend avoiding embedding-based metrics and focusing on fairness evaluations in downstream tasks.

调查表明，对于预训练语言模型的公平度和偏见进行度量的大量指标之间的比较以及使用这些指标进行评估的工作仍然困难，如果不是完全不可能的。建议避免基于嵌入的指标，并专注于下游任务中的公平度评估，以提高未来的公平度比较和评估。

使用有偏尺度衡量公平性：对预训练语言模型中偏差量化的调查