Two book reviews

I've had both of these on my shelf for some time, but haven't found time to write detailed reviews.


Google's PageRank and Beyond, Langville and Meyer (Princeton University Press).

Written by two math professors, this is the best technical account I could find of search algorithms. The math (mainly linear algebra and a little graph theory) is accessible and introduced in a self-contained way in a separate chapter. The coverage isn't limited to beautiful algorithmic ideas (the primary one being to find the dominant eigenvector of the matrix representing the graph of hyperlinks) -- the discussion includes nitty gritty details like how to treat dangling nodes, how to accelerate computations, etc. There's also a running historical summary of Google's development up to and including the IPO.

If you're wondering why I have this book, it's not just academic curiosity -- the PageRank algorithm in its basic form can be understood pretty quickly from overviews available online. I'm interested in understanding the current state of the art and the possibility of improvements ;-)


An Engine, Not a Camera, D. MacKenzie (MIT Press)

This is the best history of modern finance and options pricing theory I have yet read. MacKenzie has a sufficient understanding of the theory and of the subtle sociological issues involved (strangely, he is not an economist but a sociologist). Figures like Mandelbrot (the mathematician), Thorp (perhaps the real inventor of Black-Scholes) and Osborne (a physicist) appear along with better known economists like Samuelson, Fama, Miller, Sharpe, Black, Scholes, Merton, etc. The section on Mandelbrot and Levy distributions is especially good, as is the account of LTCM. The title is from Milton Friedman, who (controversially) characterized economic theory as an "engine to analyze the world, not a photographic reproduction of it".