As you may know, there is no general procedure to "reverse engineer" a LaTeX document.
I would proceed as follow:
- Is this article published? If so, is the journal / conference / proceedings imposing a style?
In that case, this paper was an abstract to 2011 NIPS Workshop on Bayesian Nonparametrics. It was accepted, and lead to a poster presentation, but no style was imposed (from what I saw).
- What is the department of the authors? Do they propose a LaTeX template ?
In that case, it seems that neither the Department of Mathematics of the Massachusetts Institute of Technology, neither the Department of Engineering of the University of Cambridge offer a template.
- Can I find similar documents?
In that case, I could'nt find anything (except maybe this paper and another paper by Jacob Steinhardt).
This leads to the conclusion that it looks like a custom style. Contact one of the two author, people are generally glad to share their tips and tricks concerning LaTeX.
articlewithgeometryto set the margins,titlingto customize the title (or do it completely on your own, packagetgheros(for the diagrams) andtgtermes(and its math font) to get the fonts in the document (well, actually better alternatives). – Johannes_B Feb 09 '15 at 18:05