University of Isfahan Spatial Planning 2228-7485 1 4 2012 03 20 Investigating parks equality distribution in Tehran urban zones using Theil index Investigating parks equality distribution in Tehran urban zones using Theil index 133 144 15930 FA Nasrin Ghobadi Master of Science in Economics Journal Article 2016 06 14 Parks and green areas play an important role in urban development. In fact, parks are a key element in clean environment that create opportunities for improving quality of life and making it happier and healthier.  In this case, in addition to considering for making new parks and enlarging existing ones, the fragmentation of them in different zones and urban distinct is important and should come to account, Since the equal distribution in parks and other urban services and facilities could result sustainable urban development. The Tehran Five Year Plan Law has paid attention both in equality in distribution and also green areas development. Hence, in this article the equality of parks distribution in 22 Tehran Municipality distinctions is investigated by Theil index. This index is used to measure inequality which is the maximum possible entropy of the data minus the observed entropy. It is a special case of the generalized entropy index. In this article, at first all 22 distinct of Tehran Municipality are compared respect to their park area. The results show that there is a large gap between distinct in the case of relative park areas to total area of the distinct. However, the total per capita park area has had increasing trend during the period. According to Theil index for per capita park area, there has been improving equal distribution during the period, as the index has decreasing trend so that the least value is seen in last year of the period. Parks and green areas play an important role in urban development. In fact, parks are a key element in clean environment that create opportunities for improving quality of life and making it happier and healthier.  In this case, in addition to considering for making new parks and enlarging existing ones, the fragmentation of them in different zones and urban distinct is important and should come to account, Since the equal distribution in parks and other urban services and facilities could result sustainable urban development. The Tehran Five Year Plan Law has paid attention both in equality in distribution and also green areas development. Hence, in this article the equality of parks distribution in 22 Tehran Municipality distinctions is investigated by Theil index. This index is used to measure inequality which is the maximum possible entropy of the data minus the observed entropy. It is a special case of the generalized entropy index. In this article, at first all 22 distinct of Tehran Municipality are compared respect to their park area. The results show that there is a large gap between distinct in the case of relative park areas to total area of the distinct. However, the total per capita park area has had increasing trend during the period. According to Theil index for per capita park area, there has been improving equal distribution during the period, as the index has decreasing trend so that the least value is seen in last year of the period. https://sppl.ui.ac.ir/article_15930_64b6158dc7dfece29b6390217f6ae427.pdf