Objective: This study is trying to analyze the behavior of monetary policymakers with using Taylor's rule. policy rules express how monetary policy tools respond to changes in state variables. In recent decades, has been one of the main and mental preoccupations of monetary economists  hat how monetary policymakers react to key economic variables and has led to more studies on the formulation and evaluation of monetary policy rules.Method: Since it is not expected to have a linear relationship between the variables of the model due to the existence of successive structural changes and changes in the political regime, therefore, the smooth transition threshold regression model (STR) has been used for respect to the variables of oil price changes, official exchange rate changes, inflation gap and production gap in the annual period from 2002 to 2019. It should be noted that the variables used in estimating the models are based on the degree of stationarity of the variables. According to the econometric literature, before any estimation, in order to prevent the occurrence of false regressions, it is necessary to ensure that the variables are stationary. For this purpose, the generalized Dickey-Fuller unit root test (ADF) has been used. The results obtained in table (1) show that in all the studied countries, the production gap variables, official exchange rate changes, inflation gap, oil price changes and nominal interest rate changes (for Iran; real interest rate changes) in The surface is static. In the next step, to estimate an STR model, it is necessary to determine the optimal interval for the model variables. After determining the optimal interval for the research variables, the type of model is determined in terms of linearity or non-linearity. For this purpose, the F test statistic was used. In the following, the appropriate transfer variable should be selected for the nonlinear model. To select the transition variable, any potential explanatory variable can be tested, but priority is given to the transition variable that rejects the null hypothesis of the f-test more strongly. Before estimation, model parameters using Newton-Raphsen algorithm are first checked for the existence or non-existence of collinearity between the variables of the model using the collinearity test of the variance inflation factor (Vif). In the following, the mentioned models are estimated and an attempt is made to analyze the models in which the variables have the greatest impact on the monetary policy maker and Taylor's principle is observed in them.Results: The results showed that, firstly, the reaction function of monetary policy makers in 16 selected countries is non-linear. Secondly; The findings from the estimation of the specified policy rule based on models (1), (2), (3) and (4) have shown that in all the investigated countries, by entering the variables of oil price changes and the official exchange rate into Taylor's model (model 1), the targeting of monetary policy makers is stable. Meanwhile, for the country of Iran, with the inclusion of the variables of oil price changes and official exchange rate in the Taylor model, inflation targeting is changed to production targeting. Thirdly; Based on the results obtained from the estimation of models, it can be seen that the variable of oil price changes in the countries of Algeria, Qatar, Kazakhstan, Ecuador, Colombia, Malaysia, Mexico, Belarus and Bulgaria affects the reaction function of monetary policy makers through the production gap channel and in Iran, Russia, Angola, Nigeria, Brazil, Tunisia and Azerbaijan through the official exchange rate gap channel.Conclusion: It is suggested that the central banks of the countries use key and influential variables such as: changes in oil prices, stock prices, housing prices, exchange rates, etc., because the selection of inappropriate policy goals damages the credibility of the central bank and invalidates the targeting framework.

This study investigates whether monetary and fiscal policies are consistent in reaction to the demand pressure and inflationary conditions. To answer this question, the coordination between monetary and fiscal policies was examined for the period 1988: 1-2021: 4, based on Demid’, s approach (2018) and using a model with time-varying parameters (TVP). Following the study of Kuttner (2016) in the framework of game theory, Nash equilibrium, scenarios for the interaction of these two policies were extracted in the policy matrix. The results confirm that two periods, from the first quarter of 1992 to the second quarter of 1992 (two seasons) and also from the second quarter of 2011 to the third quarter of 2011 (two seasons), were the only ones in which monetary and fiscal policymakers simultaneously and consistently tried to reduce the inflation gap. Also, in the first three seasons of 2006 and the second quarter of 2008 to the end of 2009 (7 seasons), the monetary and fiscal authorities reacted positively to the negative output gap simultaneously and had a counter-cyclical reaction to reduce the output gap in a coordinated manner. Based on these results and in the framework of the policy matrix, the Central Bank of Iran has been submissive to fiscal policies for most of the years. Therefore, it is suggested that to strengthen coordination between fiscal and monetary policymakers, establishment of some institutional arrangements and legal frameworks should be on the agenda, including the implementation of both fiscal rules and inflation targeting, and setting a legal framework for strengthening the central bank independence.

The reaction function of the monetary policy maker can provide insight into the factors influencing monetary policy decisions. Empirical estimates indicate the existence of differences among countries, whether monetary policy only reacts to expected inflation or takes into account expected production developments. This study investigates the reaction function of the Iranin central bank, focusing on the variation in nominal interest rate as the main instrument for monetary policy. For this purpose, we analyzed  the reaction function of the monetary policy authority for the annual time series period from 2002 to 2019 using nonlinear Taylor rule.Evaluating the behavior of monetary policy makers in response to changes in situational variables; Oil price changes, official exchange rate changes, inflation gap and production gap using smooth transition regression (STR) model have shown that, firstly: the reaction function of the monetary policymaker in Iran is non-linear and secondly; It can be seen that by entering the variables of official exchange rate changes and oil price changes into the model, with the increase of the production gap coefficient compared to the inflation coefficient, the inflation targeting scenario changes towards the targeting of production stabilization, and thirdly; The variable influence channel of oil price changes on the reaction function of the monetary policymaker is the official exchange rate gap.

The ultimate goal of monetary policy in Islamic economics is the most important component of the theory of monetary policy, because it governs all the principles, rules and policy tools. These goals must, in addition to being consistent and coherent in their internal and interrelationship, be in line with the ultimate goals of the Islamic economic system. In this research, based on theoretical foundations of monetary policy and the teachings of Islamic economics and explaining the main functions of money in an economy based on the theory of exchange, the expansion of Islamic monetary policy theory in the field of ultimate goals was addressed and three goals of inflation control, guidance and appropriation Money and the stabilization of the real sector in the economy were extracted and introduced as the ultimate goal of monetary policy in Islamic economics. In equilibrium, the full realization of all three ultimate ends may be because there is no theoretical conflict between the three goals, and the approach of these goals is to stabilize, balance, and create the context and the basis for economic growth. At the same time, due to special circumstances or imbalances in the economy, it may come from the realization of another goal and another purpose of interpenetration or deflection, in which case the position of a monetary policeman should be based on the criteria of preferential interest in the important and the criteria: circle The impact of politics on the general public, the degree and degree of policy impact, permanent (long-term) or temporary (short-term) policy and the positive or positive nature of the policy in question.

The purpose of this research is investigating the reaction function of the monetary policy maker in the framework of Taylor's laws and production targeting during the seasonal the period of 1370:1-1398:4, with using the Dynamic Stochastic General Equilibrium (DSGE) method and Bayesian techniques. Therefore, at first, a new Keynesian Dynamic Stochastic General Equilibrium (DSGE) model with investment adjustment costs, prices and real wage stickiness, public sector and imperfect competition, along with various shocks is designed and then with using Bayesian methods, we estimate and compare these models on the data of Iran. The results have shown that first; The impact of monetary policy shocks on the variables used in the models is in the same direction. Secondly; The effectiveness of production variables and inflation rate from monetary shocks of nominal GDP targeting law is more than Taylor's law and mainly this law is preferred by the data of Iran. Third: With the occurrence of a monetary shock within the framework of the aforementioned rules, the variables of inflation rate and interest rate have decreased simultaneously, which indicates the suitability of the variable of interest rate as a tool for the monetary policy maker. . . .

Estimates of instrumental rules can be utilized to describe central bank's behavior and monetary policy stance. In the last decade, considerable attention has been given to time-varying parameter (TVP) specification of monetary policy rules. Constant-parameter reaction functions likely ignore the impact of model uncertainty, shifting preferences and nonlinearities of policymaker's choices. This paper examines the evolution of monetary policy reaction function in Iran via estimating a time-varying parameter (TVP) specification in the 1990: 2-2014: 4 period. We try to find out whether there is a significant time variation in coefficient of CBI (the Central Bank of Iran) reaction function. The main findings are threefold. First, monetary policy rules changed over time, hence making relevant the application of a time-varying estimation framework. Second, the monetary instrument smoothing parameter is much lower than typically reported by previous time-invariant estimates of policy rules. Third, CBI does not systematically follow instrumental rule to fight inflation. During the whole sample, there is no quarter in which the inflation gap coefficient is negative and significant; therefore, monetary policy has not counteracted inflationary pressures.