DL-1-VS (Table 9) uses smoothed precision, but unlike DL-0, DL-1-VS does not use a fixed smoothing constant ; rather varies from feature to feature.
y-1/DL-EM reduces H; the others reduce K. y-1/DL-EM-Λ EM inner loop that uses labeled examples only y-1/DL-EM-X EM inner loop that uses all examples y-1/DL-1-R Near-original yarowsky inner loop, no smoothing y-1/DL-1-VS Near-original yarowsky inner loop, "variable smoothing" yS-P Sequential update, "antismoothing" yS-R Sequential update, no smoothing yS-FS Sequential update, original yarowsky smoothing restricts the data sets on which the algorithm can be shown effective, but also for additional internal reasons.