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The aim of this paper is to consider the effects of monetary policy on production and prices through asset price channel (the housing price index) in Iran during 1368Q1 to 1387Q4. By Vector Error Correction (VEC) Model, the effect of monetary policy has been considered through this channel. In general, the results show that the debt of banks to the central bank as instruments of monetary policy through the housing price index, at least in the short run could increase the production level and decreases prices. Thus central bank with given facilities to banks can directly and through the housing price index strengthen production level and control prices in the short run. Also we found that shock of the required reserve ratio in general, directly affects production levels and don’t have any effect on production level and prices through the housing price index. Therefore, in using of these tool as instruments of monetary policy, the housing price index channel in monetary transmission policy, has a little effect and only on the production.

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According to Taylor (1993) rule, the monetary authority responds to deviations of output and of inflation from their targets through nominal interest rate fluctuations regarded as policy instrument. Another specification that has received considerable attention is that policymakers may have asymmetric preferences with regard to their objectives during recessions and expansions. Since according to Law for Usury (Interest) Free Banking of Iran, the objective of the central bank is not the control of interest rate, instead it is money growth rate which is used as an instrument, in this study we introduce a money growth rate reaction function and we use it to test the asymmetry in central bank behavior during recessions and expansions. The estimation results of a Markov Switching model for the period 1367:1 to 1387:2 show that the central bank sensitivity toward output is more during the recessions while its sensitivity toward inflation is more during the expansions.

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The commitment and forward-looking behavior of central bank is of great importance. Commitment imposes less social costs on the central bank and the public. However, while there is wide agreement on the importance of commitment, there is much less consensus on how to implement commitment through targeting or instrumental rules. In this paper, we have estimated a basic New Keynesian model in Iran economy based on quarterly data over a sample period for 1990-2010. Then, we introduced a kind of instrumental rules that is called Speed Limit rule. The main feature of this rule is that the output gap is replaced by the changes in the output gap in the central bank's loss function. Then, by calculating appropriate weights under alternative targeting rules, we showed that this rule has the lowest social costs. Then, assuming the use of interest rate as primary monetary policy by the central bank, it is optimal to consider the role of the changes in the output gap (i.e. speed limit rule) in addition to the role of inflation and the output gap. As we expected, the estimation results of this instrumental rule in Iran economy showed that this rule has not been used for determining the interest rate. In other words, among the variables considered, only inflation rate has a positive and significant relationship with the interest rate, and the output gap and the changes in the output gap are not used in determining the interest rate.