[how_gauche]

Similar dynamic programming idea from Zhang + Shasha 1992: http://www.cs.nyu.edu/shasha/papers/treebook3.pdf

[dahart]

I think this is the same Zhang with a later paper. This is the most direct mapping of edit distance from strings onto trees that I know of, and uses dynamic programming: http://www.sciencedirect.com/science/article/pii/03043975958...