8. An apparatus, comprising: a memory configured to store a classifier, a training dataset comprising training instances having respective training features, and a production dataset comprising production instances; and a processor configured: to apply a classifier to the training dataset, thereby generating a training classification that assigns, to each of the training instances, one of a plurality of categories, the classifier having an expected classification, to detect a classification bias in the training classification relative to the expected classification, to define, in response to the classification bias, a calibration matrix based on conditional probabilities of features of the production dataset given occurrences of corresponding training features; to apply the classifier and the calibration matrix to the production dataset, thereby generating a production classification quantification that assigns, to each of the production instances, one of the plurality of categories.
8. An apparatus, comprising: a memory configured to store a classifier, a training dataset comprising training instances having respective training features, and a production dataset comprising production instances; and a processor configured: to apply a classifier to the training dataset, thereby generating a training classification that assigns, to each of the training instances, one of a plurality of categories, the classifier having an expected classification, to detect a classification bias in the training classification relative to the expected classification, to define, in response to the classification bias, a calibration matrix based on conditional probabilities of features of the production dataset given occurrences of corresponding training features; to apply the classifier and the calibration matrix to the production dataset, thereby generating a production classification quantification that assigns, to each of the production instances, one of the plurality of categories. 10. The apparatus according to claim 8 , wherein the calibration matrix comprises multiple matrix entries, each of the matrix entries comprising a given feature and an adjustment factor.