Hi:I am building a model to evaluate treasury butterfly trades. The basic idea is for the model to run every night and go through a number of triplets of possible outstanding treasuries; for each possible triplet picked, calculate the weights for 50/50, regression weighted, and pca butterflies; calculate the butterfly spread; and then apply a number of heuristics to rank the triplets to present to the analysts the next day.Has anyone done something like this before and can recommend the best way to approach this in terms of software selection? I don't know any of the statistical packages to start with, so am looking to learn one and am looking to use MatLab just because I have access to a copy to use. Any other ones and I will have to buy a license, I guess, and since am doing this on my own, don't want to spend too much money.Thanks!

Have a look at R (www.r-project.org). It's the free clone of S+ and it's very powerful. You'll have to learn it but it's really worth the effort. HTH