What are some good ways of estimating 'approximate' semantic similarity between sentences?

Question

I have been looking at the nlp tag on SO for the past couple of hours and am confident I did not miss anything but if I did, please do point me to the question.

In

Answer 1

Latent Semantic Modeling could be useful. It's basically just yet another application of the Singular Value Decomposition. The SVDLIBC is a pretty nice C implementation of this approach, which is an oldie but a goodie, and there are even python binding in the form of sparsesvd.