The IMF Working Papers series is designed to make IMF staff research available to a wide audience. Almost 300 Working Papers are released each year, covering a wide range of theoretical and analytical topics, including balance of payments, monetary and fiscal issues, global liquidity, and national and international economic developments.
Using the ARFIMA-FIGARCH model, this paper studies the efficiency of the Japanese equity market by examining the statistical properties of the return and volatility of the Nikkei 225. It shows that both follow a long range dependence, which stands against the efficient market hypothesis (EMH). The result is valid for all sample periods, suggesting that the recent equity market reform has not produced major efficiency gains.