جستجوی مقالات مرتبط با کلیدواژه « Agricultural Prices » در نشریات گروه « اقتصاد کشاورزی »

Price stability of agricultural products is related to the stability and development of the agricultural products market. Inflation in Iran, despite the intense fight against it, is increasing at a worrying rate, and has become the most important economic problem in the country. This study investigates the relationship between inflation and expected inflation with price fluctuations of agricultural products in Iran using self-explanatory method and Granger causality test during the period 1991-2019 in the form of quarterly data.The results showed that the inflation rate has a positive and significant effect on price fluctuations of agricultural products during the study period. Expected inflation variable also has a positive and significant effect on price fluctuations in agricultural products. The results of Granger causality test also showed that there is a two-way cause and effect relationship between expected inflation and price fluctuations in agricultural products. There is also a two-way causality relationship between inflation and expected inflation. There is also a one-way causal relationship between inflation and agricultural price fluctuations.

 Today, the food-energy nexus is a vital issue. Energy in the food production chain is an essential feature of agricultural development and a critical factor in achieving food security. Energy use in the agricultural sector has increased to respond to the growing demand of the population, as well the limited supply of cultivated lands, and the desire for high standards of living. Therefore, the agricultural sector is heavily dependent on energy that affects agricultural prices. Agricultural price fluctuations are one of the most critical challenges for policymakers. The rapid rise in food prices has a significant negative impact on social welfare, especially the poor in developing countries, which is an issue that is more critical in developing countries than in developed countries. According to the Food and Agriculture Organization (FAO) report in 2018, the food world price index increased from 89.6 to 229.9 during the period from 2002 to 2011. Our literature review shows a distinct lack of research on modeling and analyzing the linkage between agricultural input price shock, especially energy and agricultural commodity prices in Iran.

The Markov Switching model is a popular non-linear time-series model that involves multiple equations and can characterize the time-series behaviors in different regimes. This model is suitable for describing correlated data that exhibit distinct dynamic patterns during different periods. So, considering the sensitivity of food security and the impact of agricultural input, the main objective of this paper is to develop an econometric model to gain reliable insight into the impact of energy consumption on agricultural inflation, using the Markov Switching approach. To estimate this equation, we will run a MS-AR model, some preliminary tests, such as unit root test and stability test, are employed to ensure the reliability of MS-AR estimation results.

Due to use of time series data, it is necessary to check the stationary status of variables. We performed a common non-linear unit root test (Kapetanios, Shin and Shell (KSS), Zivot and Andrews, Lee and Strazicich). These results reveal that we can significantly reject the null hypothesis of unit root for API, PPI, FPI, and EC, implying that all four variables considered in this study are stationary with structural breaks at levels. The Markov-Switching model has the various types that each of these is a particular component of the regime-dependent equation. Therefore, to choose the best type, the Akaike information criterion was used, and the model with the minimum value was selected as the optimal one. After model estimation and selection, the LR test indicated that the hypothesis of linearity could be rejected in favor of a Markov switching model. According to this model, the period of the Markov switching model estimation is classified into two regimes. Approximately, all the estimated coefficients of the MSIAH (2) - AR (5) model are found to be significant at the conventional level.

The estimation results are consistent with theoretical foundations illustrating the importance of input prices and energy consumption on agricultural commodity prices. As with most experimental studies reviewed, this study has also shown energy consumption has a negative impact on agricultural commodity prices. In other words, it can be contended that during the study period, agricultural input prices have been influential factors on agricultural commodity prices. The findings revealed that the low inflation rate and high inflation rate regimes are stable and that only extreme events can switch regimes. The results of the MS model showed that the effect of input prices on agricultural inflation is different in regimes. In the case of energy, the impact of energy consumption on agricultural commodity prices in the high inflation rate regime is less than the low inflation rate regime because the elimination of energy subsidies policy has been applied in the second regime (high inflation rate). Thus, the results indicate the asymmetric impact of energy consumption shocks on agricultural commodity prices. The effect of agricultural input prices on agricultural commodity prices indicates that Iranian agriculture is significantly affected by changes in input prices. In this study, changes in input prices were caused by various shocks, such as the elimination of energy subsidies and drought. Therefore, it can be concluded that the elimination of energy subsidies and drought were, directly and indirectly, able to affect agricultural inflations through the price of inputs. In conclusion, planners and policymakers must pay attention to this asymmetry in agricultural commodity prices volatility to increase the price stability in agriculture as much as possible by appropriate policy tools.

Considering the effect of money supply increase on agricultural prices، Identification of the relationships between variables plays an important role in the implementation of appropriate economic policies. This research attempts to probe the equilibrium relationship between money supply increase and the prices of economic sectors focusing on Iran’s agricultural sector based on the quarterly time series data set during the period of 1991-2010. For this reason the relationship between variables is analyzed using Johansen’s cointegration test along with a vector error correction model (VECM) and later the relationship between variables is extracted using the impulse response functions (IRF). Estimation results indicate that supply money increase has a stronger influence on agricultural prices in the short-run، while industrial and services prices are fixed. In addition، the changes of supply of money in the long-run has direct effect on agriculture، industry and services price، but the strongest impact on agricultural prices is caused by industrial price variability.

Detection of structural changes and shocks in time series is a topic that has been discussed for many decades. Ignoring these change points in time series can lead to serious problems with economic models of time series. the purpose of this paper is investigation of multiple structural breakdate in prices of milk, egg, hen meat, sheep meat and beef for the period from January 1380 to December 1391 by means of QLR statistics. The results showed that there are one breakdate in price of milk, 2 braekdate in egg and 2, 0 and 2 breakdate in hen meat, sheep meat and beef, respectively. Some of macroeconomic policies such as unified exchange rate policies, targeted subsidies have been the effective factors on the occurrence of structural breaks in the series of prices.