Regional inequality measurement:methods and evaluations

Regional inequality is one of the major subjects of research on China,and is a major concern to the Chinese government.On the basis of analyzing the structure differences of some major indexes for measuring regional inequality,the rural regional inequality changes in China at provincial level from 1980 to 2002 is described by different methods respectively.It is found that the changes of different indexes show the same trend in a longer period of time,but some in a shorter period.All the methods showed that China's rural regional inequality has an overall increasing trend with a short period of decreasing in the whole process of reform.However,the decomposition of the Theil's regional inequality reveals that since 1987,the interregional inequalities among the eastern,central and western regions have been more serious than the provincial inequality within regions.The further factor decomposition of the Gini index shows that farmers' wage component contributes more than 66% to the total inequality index and is the most important factor resulting in rural total regional inequality.It is proposed that any conclusions from a short period of data analysis are inadeguate.When analyzing driving forces of regional inequality,long-term data should be used.The further decomposing analysis of different indexes shows that each method has its own advantages and disadvantages.The Gini index is suitable for factor analysis but cannot be decomposed by regions.The greatest advantage of the Theil's index is that it can be decomposed by different levels of regions and is very useful for different spatial scale analyses of regional inequality.Standard Deviation is more suitable for simple analysis of regional inequality in China.Compared with the above three indexes,the Atkinson index is rarely used.But when regional inequality is very small,it is the only one that can be used for analysis.