رضا محسنی

This study aims to estimate the demand function for recycled paper in the Iranian economy during the seasonal period of 2000 to 2021. The Johansen-Juselius cointegration method was used to identify the factors influencing demand in both the long and short term. Quarterly data were generated from annual figures using the Denton method, and the model was specified in a linear logarithmic form. The model’s variables include per capita consumption of recycled paper, its price, the price of virgin paper, the percentage of internet users, and Gross Domestic Product (GDP). A dummy variable was also included to account for the removal of the import tariff in 2018. The results indicate that recycled paper is a necessary and inelastic good. In the long term, it becomes an inferior good, meaning that as income and welfare increase, consumers and producers shift towards higher-quality virgin paper. In the short term, demand is influenced by changes in GDP, the price of recycled paper, and the internet. The price elasticity of demand is very low (0.012%), suggesting that price changes have a negligible impact on the quantity demanded. The error correction model (ECM) coefficient of -0.51 indicates that half of the short-term disequilibrium is corrected in each period. These findings emphasize the importance of government policies in encouraging recycling and managing the market. Given Iran's limited forest resources, focusing on this sector can contribute to economic and environmental sustainability. Future research could explore the impact of tax and subsidy policies on the paper recycling industry.

This study examines the impact of NAFTA and USMCA free trade agreements on trade deficits and net agricultural trade between the United States, Canada, and Mexico, focusing on HS6-digit level agricultural commodities from 1994 to 2020. Using ARDL and gravity models, the results show that NAFTA led to increased trade volumes and improved net trade positions, particularly for Mexico, whose net agricultural trade surplus with the U.S. grew by approximately 24%. In contrast, the United States experienced a 15% increase in its agricultural trade deficit under USMCA, while Canada’s balance remained relatively stable, with fluctuations within a ±5% range. The ARDL model indicates that GDP (β = 0.47, p < 0.01), exchange rate (β = 0.82, p < 0.05), and government spending (β = -0.39, p < 0.1) significantly influenced bilateral trade deficits. In the gravity model, GDP per capita had the strongest positive effect on net agricultural trade (β = 1.75, p < 0.01), while agricultural value-added had a negative impact (β = -0.61, p < 0.05). These findings suggest that structural changes in trade agreements, combined with macroeconomic conditions, have measurable effects on national trade balances. For countries like Iran, the study highlights the importance of designing bilateral trade frameworks that promote agricultural competitiveness, maintain exchange rate stability, and protect vulnerable producers. Evidence-based trade policy can help Iran achieve greater trade resilience and improve its position in regional agricultural markets.