MNB uses add-1 smoothing to estimate the conditional probability of the word "resources" in each class as θ + w = 1+1 216+33504 = 5.93e-5, and implying that "resources" is a negative indicator of the Earnings class.
mNB-Fm attempts to improve the noisy estimates θ + w and θ − w utilizing the robust estimate for P (w) computed over unlabeled data.