  We report on a method for compiling decision trees into weighted finite-state
transducers. The key assumptions are that the tree predictions specify how to
rewrite symbols from an input string, and the decision at each tree node is
stateable in terms of regular expressions on the input string. Each leaf node
can then be treated as a separate rule where the left and right contexts are
constructable from the decisions made traversing the tree from the root to the
leaf. These rules are compiled into transducers using the weighted rewrite-rule
rule-compilation algorithm described in (Mohri and Sproat, 1996).
