Examining the effect of rural roads expansion on the rural poverty index in Iranian provinces

Introduction
Poverty means the inability to meet one's basic needs and necessities of life such as food, clothing, housing, etc. The concept of basic needs varies based on time and place, and it includes the minimum needs to survive with an average standard of living. Poverty limits human development and has long-term and extensive harmful consequences (Arzerum Chiller, 2005). The poverty phenomenon has long accompanied mankind and has been one of the basic socio-economic issues of humans. In recent decades, despite the expansion of the implementation of economic reform, poverty and inequality are still seen in most countries. Also, due to their comprehensive consequences, poverty and inequality are nowadays the focus of international organizations, government officials, economists, and of course sociologists more than ever. The significance of poverty reduction has always been focused on in religious teachings. Besides, elimination of poverty and deprivation of members of society and ensuring their well-being has strong theoretical foundations in the Holy Quran and Islamic teachings. Therefore, reducing poverty and respecting human dignity must be operationally considered in economic and social plans (Hekmati Farid, 2013). Given these teachings and the importance of poverty reduction in the country's development, paying attention to the poor and supporting them can be seen in Articles 2, 3, 21, and 29 of the Constitution, as well as Article 43, which pays particular attention to erase poverty and deprivation from society.
Data and methodology
The general econometric model used for examining the impact of variables and factors affecting the rural poverty index with a focus on rural roads is described as follows:
 
i=1,2,…,28                     t=1,2,…,15
Where the variables are:
Sen = Amartya Sen poverty index (rural); calculation of the Sen index for rural areas of Iranian provinces
RAH = Existing rural road (km) of the Roads and Transportation Organization
El = Number of villages receiving electricity recorded by the Statistics Center of Iran
He = Number of rural health centers recorded by the Statistics Center of Iran
Educ = literacy rate of the rural population
AB = Number of villages with drinking water recorded by the Statistics Center of Iran
In = average rural household income
khc = Food expenditure of rural households
AGG = Agricultural sector growth rate
It must be mentioned that the model was estimated in two modes to examine the short-term and long-term effects of rural road development on the rural poverty index. Mode one occurs with the Rah and DRah variables, which represented the total number of the rural roads in the province in each year and the difference of rural roads in the province in each year, respectively. Mode one showed whether or not the development of rural roads each year has affected poverty. Also, the model was estimated in different modes with different variables to avoid the collinearity problem. This model was designed based on panel data and its coefficients were estimated using conventional panel data econometric methods.
Analysis of findings and conclusion
As mentioned earlier, in addition to the transportation of agricultural products, roads reduce the time of transportation and the final price of the produced goods. Safe and proper roads and transportation networks are essential for accessing other important centers of the country. Besides, according to many experts, the effect of this factor on the expansion of other developmental factors is undeniable and it paves the way for significant development in various ways.
Providing physical infrastructures plays an important role in the economic development process and facilitates accessing infrastructures such as education and health facilities, water supply, supply of electricity, and transportation, which in turn enhances welfare. Because it seems that the development of infrastructures such as investments in healthcare services, electricity and water supply, development of irrigation and drainage networks, construction of rural roads, and establishment of educational centers in rural areas improve income distribution and decrease the poverty rate.
According to the statistics of the National Roads and Transportation Organization, the length of rural roads (asphalt and dirt) was 100316 km in 2005, and it was increased to 128139 in 2016. Evidence obtained from comparing rural road expansion and poverty reduction showed that the development of rural roads can have a positive impact on poverty reduction.
Based on the research findings, it could be concluded that the expansion of rural roads affected rural poverty.
Results and Discussion
According to the results of estimations, the expansion of rural roads could not influence poverty in short term, but it could have a diverse influence on poverty, in the long run, meaning that it could reduce poverty.
The negative value of the constructed rural road coefficient indicated the negative effect of this variable on the Sen poverty index. In other words, an increase in the constructed rural road led to a reduction in rural poverty.
The coefficient associated with the average rural income had a negative value and significance, which indicated that the increase in the income of rural households throughout the studied years reduced rural poverty.
The coefficient related to investments in water resources had a negative value and was insignificant, which indicated that this type of investment did not have a direct effect on poverty reduction.
The coefficient associated with the variable of the number of villages supplied with electricity was significant and had a negative value, which was an indication of the inverse effect of this variable on poverty.
The coefficient of the effect of agricultural sector growth rate on rural poverty was insignificant, which was indicative of the direct effect of this variable on poverty.