Disambiguation of morpho-syntactic features of African American English -- the case of habitual be
Harrison Santiago, Joshua Martin, Sarah Moeller, Kevin Tang
TL;DR
The paper tackles NLP bias against African American English by addressing the rare and ambiguous habitual 'be' in AAE. It introduces a two-stage pipeline—rule-based syntactic filters to prune non-habitual instances and data augmentation to balance habitual ones—enabling unbiased classifiers trained on CORAAL data. On a corpus with about $477$ habitual and $4{,}656$ non-habitual cases, the ensemble classifier reaches approximately $F_1=0.65$, with reduced variance when using the balanced data. This approach demonstrates a practical strategy to mitigate low-resource, dialect-specific features in NLP and could extend to other AAE morphosyntactic phenomena and future transformer-based models as data availability increases.
Abstract
Recent research has highlighted that natural language processing (NLP) systems exhibit a bias against African American speakers. The bias errors are often caused by poor representation of linguistic features unique to African American English (AAE), due to the relatively low probability of occurrence of many such features in training data. We present a workflow to overcome such bias in the case of habitual "be". Habitual "be" is isomorphic, and therefore ambiguous, with other forms of "be" found in both AAE and other varieties of English. This creates a clear challenge for bias in NLP technologies. To overcome the scarcity, we employ a combination of rule-based filters and data augmentation that generate a corpus balanced between habitual and non-habitual instances. With this balanced corpus, we train unbiased machine learning classifiers, as demonstrated on a corpus of AAE transcribed texts, achieving .65 F$_1$ score disambiguating habitual "be".
