Measurement of Poverty Intensity in Iran: Applying Sen-Shorrocks-Thon(SST) Index

SST Index is an appropriate instrument to measure the poverty intensity. This index can measure the poverty intensity considering number of the poor people and depth of poverty and inequality among them and allows us to decompose poverty into three aspects: Is there an increase in the number of the poor? Atlas the poor become poorer? And is there higher inequality among the poor? In this paper through SST Index the poverty intensity in Iran during the years 2003 and 2004 has been calculated for urban and rural areas using the data obtained from the Household Income and Expenditure Survey conducted by the Statistical Center of Iran and considering the absolute poverty line of 2300 calories with the percentage of changes compared over the two years. Also, the portion of factors constituting SST Index over the said years is specified. In order to determine the statistical reliability of the estimations made, the confidence interval of the index has been calculated with the application of Bootstrap Method. The findings reveal that the poverty intensity in 2004 compared with that in 2003 increased up to 1.7 percent in urban areas and reduced to 1.8 percent in rural areas and the changes are significant at level of 90 percent confidence. In addition, the poverty intensity over these two years has been higher in urban areas than in rural areas.