عنوان مقاله [English]
The main objective of this research is to estimate the demand model for crude oil and natural gas in the country during the period from 1988 to 2015 and also to predict crude oil and natural gas demand functions in Iran during the sixth development plan with the aim of studying the effect of important variables affecting their consumption in the country. VAR - VECM model is used to investigate the relationship and the effects of variables and the short-run and long-run relationship between variables, and finally, extracted model has been used to predict crude oil and natural gas demand in the country at 1400 horizon. The results indicate that: (1) income elasticity is low and the sensitivity of oil consumption to changes in income (here, per capita income) is small. (2) There are no long-term causal relationship between intrinsic independent variables and exogenous independent variables, such as oil price and natural gas prices, towards natural gas consumption and per capita income. (3) In the short term, there is no causal relationship from natural gas consumption, natural gas prices, oil prices, and per capita income towards crude oil consumption. (4) Variance decomposition for oil consumption variable indicates that in the long run, natural gas consumption has a significant contribution to explaining changes in crude oil consumption.