Estimating the Lorenz Curves Using Alternative Parametric Models The Case of Iranian Rural and Urban Population

The main purpose of this study is to estimate the Lorenz curves of Iran rural and urban income distributions, using alternative parametric models. Alternative parametric Lorenz curves are fitted to income grouped data of Iranian family expenditure surveys in 1999, 2004 and 2009. Then the best fitting models are chosen based on Theil index for goodness of fit, for every year and area. Results show that, for urban population, Chotikapanich, Ortega and Rasche are the best fitting models in 1999, 2004 and 2009 respectively. With respect to rural population, Rasche model is the best in every studying year. Moreover, the comparison of income distribution among rural and urban populations illustrates that, while the income inequality is improving for both populations over time, rural population has a better situation than urban in 2009, in contrast to its situation in other given years.