The choice of age groups of 40-49, and 60-69 are peculiar, but understandable. I thought Japan's baby boomer generation is about the same as American ( not sure), though Japan has more aged people (not sure relative to which group). It is clearly Japan's stock market reached pieak 10 years earlier than the U.S. A few European counties' data may worth the analysis.
There is no doubt that the amount of moeny poured into the market affects the market valuation. With the computer/internet age, the access to the market is much easier for average Joes. I wonder whether there are some other indictor better than the M/O ratio, which has only 61% prediction rate.
