Several environmental goods and services are not traded in markets. This has serious consequences for private decision making. Economists have used methods for valuing goods and services provided by the environment. In this paper we have applied a method named Hedonic Price to estimate the household's Marginal Willingness to Pay (MWTP) of for air quality improvement in metropolitan Tabriz. Results of a survey of 1023 households show that the technique works satisfactorily. Air pollution has a significant negative effect on property values in the polluted areas. The average households MWTP for a unit decrease in air pollutant is estimated about 110000 Rials. This shows that rent of houses located in relatively pollutd areas is less than those located in non polluted area.

In many plains of Hamedan province, free distribution and low water subsidies paid by farmers have led to its overexploitation at the fields, which can threat the existing water resources and agricultural sustainable development in the region. Undoubtedly, one of the most important tools for optimal allocation of water resources is economic valuation, which emphasizes the long-term development strategy of the country. In this regard, the purpose of this study was to determine the economic value of agricultural water in potato fields in Razan-Ghahavand plain of Hamedan province using two approaches; production function and Willingness to Pay farmers using conditional valuation method (CVM). The required information was collected by completing a questionnaire from 150 potato farmers using a two-stage cluster sampling method in 2015-2016. In order to achieve the research objectives, the estimation of various forms of production functions was used, and the best form of the function was determined according to the results obtained by the transcendental production function. The results of the production function method showed that the average economic value of water producing potato crops was 2461 Rials per cubic meter. Also, the average Willingness to Pay farmers of this product after estimating the Logit model was 3452 Rials per cubic meter. Regarding the reported results, better achievements can be derived, if the water pricing policy is depended on effective factors, including the Willingness to Pay farmers, as well as the farmers' participation in decision-making.

Low gasoline prices in Iran, as well as the high rate of car ownership, have been the main reasons behind increased air pollution, network congestion and other relevant problems in Iranian large cities for a number of years. As it is clear that relevant changes would affect individual mode of life choices and their resulted demand, the effects on the supply side are also noticeable. In this research, an attempt has been made to analyze the "Willingness to Pay" concept for gasoline prices and to investigate the effect on the fuel demand function. The stated preference data, gathered through a post-back method questionnaire, provided the required data for modeling the "Willingness to Pay" for gasoline prices for the city of Tehran. A one-stage ordered Probit and a two-stage (binary and ordered) Probit model have been calibrated in an extensive model development process. From the results of the developed models, one can determine the society's Willingness to bear the new gasoline price. The results of the "Willingness to Pay" models showed that high levels of education, professional status, age and ownership of expensive car models have positive effects on "Willingness to Pay". The distance between origin and destination is the major variable that negatively affects a higher fuel price. The results also indicate a rather higher "Willingness to Pay" in Iran (Tehran) compared with other countries. No significant difference was observed between the one-stage and the two-stage modeling processes.

Waste is a by-product of human life. Nowadays, municipal solid waste is being produced in excessive amounts and in this way, both developing and developed countries are facing challenges regarding generation of waste. Economic development, urbanization and improved living standards in cities have contributed to increasing the amount and complexity of solid waste produced. The present study was conducted in the residential area of main Boulevard Gulberg, Lahore to determine the present methods and efficiency of current solid waste management facility and to estimate the Willingness of the selected households to Pay for the improvement of solid waste management through a questionnaire survey. It was found that current solid waste management system in the area is fair but needs more improvement in terms of improved collection efficiency and rates, recycling bins, and segregation of waste at storage. According to the questionnaire survey, the majority of the respondents despite belonging to middle-class incomes are willing to Pay an amount less than USD 4.8 for the improvement of waste management facility in the area. The area lacks a frequent collection of waste containers. Therefore, there is a need for up gradation of storage and collection facilities in terms of increase in collection efficiency and rates, an introduction of the recycling facility and segregation of waste at source. Waste storage and collection sites of the area should be monitored periodically and waste should be disposed of in a scientific manner in sanitary landfills.