  In this paper we examine inefficiencies and information disparity in the
Japanese stock market. By carefully analysing information publicly available on
the internet, an `outsider' to conventional statistical arbitrage
strategies--which are based on market microstructure, company releases, or
analyst reports--can nevertheless pursue a profitable trading strategy. A large
volume of blog data is used to demonstrate the existence of an inefficiency in
the market. An information-based model that replicates the trading strategy is
developed to estimate the degree of information disparity.
