  Classifiers tend to learn a false causal relationship between an
over-represented concept and a label, which can result in over-reliance on the
concept and compromised classification accuracy. It is imperative to have
methods in place that can compare different models and identify over-reliances
on specific concepts. We consider three well-known abusive language classifiers
trained on large English datasets and focus on the concept of negative
emotions, which is an important signal but should not be learned as a
sufficient feature for the label of abuse. Motivated by the definition of
global sufficiency, we first examine the unwanted dependencies learned by the
classifiers by assessing their accuracy on a challenge set across all decision
thresholds. Further, recognizing that a challenge set might not always be
available, we introduce concept-based explanation metrics to assess the
influence of the concept on the labels. These explanations allow us to compare
classifiers regarding the degree of false global sufficiency they have learned
between a concept and a label.
