Selection of the most relevant terms based on a max-min ratio metric for text classification.

•We Illustrated weaknesses of balanced accuracy and normalized difference measures.•We proposed a new feature ranking metric called max-min ratio (MMR).•MMR better estimates the true worth of a term in high class skews.•We tested MMR against 8 well-known metrics on 6 datasets with 2 classifiers.•MMR statistically outperforms metrics in 76% macro F1 cases and 74% micro F1 cases.