Here is the paper the conclusions are coming from: http://economics.sas.upenn.edu/~jesusfv/comparison_languages.... I linked to this blog post instead because it gives a better summary of the paper for people who don't want to read the whole thing.

The author of the blog post raised a few points that I thought were interesting and that I'll provide my own answers to here. Feel free to comment if you disagree with me.

> Why would anyone prefer Python, given that there is a much faster, free alternative in Julia, which is just as easy a language to program in?

I've used Julia a bit and the lack of libraries was frustrating. It is getting better now, but you'll still have to write a lot of stuff from scratch if you decide to use it.

> What justification is there for preferring R to Matlab, other than cost?

R makes it very easy to perform exploratory analysis on a dataset. Matlab might be similar, but I don't have experience with it.

> Why does anyone bother with Java? If speed is the critical issue, there are faster alternatives. If you like the relative simplicity of the syntax, Julia is cleaner, simpler and just as fast in execution.

I agree with this. I've never enjoyed programming in Java, but some people seem to like the large number of libraries available.