I finally got around to reading Ralph Vince’s latest The Leverage Space Trading Model (for a brief summary see this magazine article in Futures), and I’m happy to say that the book was very helpful in approach and example. I especially enjoye...

Recently, the good folks at Infochimps.com rolled out a series of new APIs to add to their already impressive set of data resources. I have been in a perpetual state of catch-up since the new year, so I have only now got around to adding some of these new APIs to the infochimps R package. Here

In my last two posts I talked about Ordinary Least Squares, then extended this discussion to the multiple predictor case and briefly talked about some of the problems that may arise. These problems can include omitted variable bias, heteroskedasticity, non-normality, and multicollinearity. Most of these problems are relatively minor in practice and have easy fixes,...