The evolution of regional income distribution in Japan

Using data on per capita income of Japan's 47 prefectures between 1955 and 1997, this paper shows that one of the most popular measurements of convergence, σ-convergence, is not invariant with both transformation and definition of dispersion. Measured by the standard deviation, the actual per capita income has diverged, whereas measured by the coefficients of variation, it has converged since 1955. The log of per capita income and relative income of all prefectures to Tokyo, however, have converged regardless of the measurement of dispersion. In addition, through the estimation of density function and transition matrix, the intradistribution dynamics of each prefecture's per capita income is identified.