Perplexity in Markov N-Gram Models

While implementing the perplexity function on Markov n-gram models as it is described on page 14 of PDFJurafsky & Martin's SLP to appear, I came across some floating point overflow, underflow issues and had to come up with equations to avoid them.

Here is PDFmy solution in detail and C#its bigram implementation.

It took me a lot of whiteboarding and a few hours to figure this one out but the resulting libcorsis code is %100 foreign intellectual property free ^_^.

I am now looking for ways to analyze distributions graphically and testing different encapsulations of probability values and their interaction with the public API.

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