How To Calculate Recombination Rate From R^2 Data?

Question

[Adrian Pelin]

If all I have is NGS and a few isolates, is there any way to calculate recombination rate? Based on allele frequencies?

[kumar.vinod81]

Have you tried LDHAT?

[Adrian Pelin]

I know it is able to do it, I am however interested in the theory behind it. What does r^2 actually mean? I know it's association of different genotype frequencies, but what does it mean when it is very high or very low in terms of recombination?