well the realistic FDFs can be reconstructed and how precisely the characteristic quantities such as the dispersion, skewness and kurtosis can be obtained by RM synthesis and other sophisticated methods [@and11; @fri11; @bec12; @aka13]. We will pursue these issues in near future.

K.T. is supported in part by the Grant-in-Aid from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan, No. 23740179, No. 24111710 and No. 24340048. T.A. acknowledges the supports of the Japan Society for the Promotion of Science (JSPS). D.R. acknowledges the supports of National Research Foundation of Korea through grant 2007-0093860.

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