bijan bidabad

The relationship between nominal interest rates and inflation is one of the most important issues in macroeconomic issues. Knowing this relationship and knowing the direction of this relationship will have many benefits for all economic and monetary policymakers. In this study, by expanding the theory of quantity of money, we examine the relationship between nominal interest rates and inflation rates and test this relationship using the gentle transition regression approach during 1352-96. The results show that as interest rates rise (especially when the interest rate exceeds its threshold), its impact on inflation increases. Also, the effect of interest rates on the general level of prices does not have a severe effect and changes in parameters are slow. Therefore, it can be concluded that interest rate instruments cannot be used to control high inflation and the use of policies that reduce the speed of money circulation can be more effective in controlling the general level of prices. This result shows in general terms that in the long run, interest rate income that enters the economy from payment to the factors of production is practically compensated and eliminated by reducing the purchasing power of money due to the increase in the general level of prices in society. Perhaps this can be considered as one of the wisdoms that God Almighty has said in the Holy Qur'an about the sanctity of usury: "God forbid usury" means that God eliminates usury; cited.

Markowitz's model which determines the weight of each stock in the portfolio is based on the optimal choice of stocks in order to maximize the expected returns. However, this theory through paying special attention to the concept of total risk reaches to an efficient frontier which undoubtedly the portion of unsystematic risk that the market doesn’t reward will not stand in the minimum level. Besides, Sharpe’s theory presents a model using some simplifying assumptions which attains a new efficient frontier in which although the concept of systematic risk governs it, its fundamental defect will absolutely be applying market portfolio in the case of investing. This article aims to combine the theories of Markowitz and Sharpe to introduce a new model. This new model is much better and more efficient in comparison to Markowitz’s efficient frontier. Moreover, it reforms the exiting defect in Sharpe’s model The superiority of proposed model over Markowitz and Sharpe's traditional models from the view point of theory is definitely proven through paying attention to unsystematic risk, eliminating some assumptions of the traditional models and finally through finding the optimal portfolio of stocks for large cement corporations in Tehran stock exchange market.

In this paper, the relationship between exchange rate and interest rate is re-examined through a theoretical expansion and reformulating of the quantitative theory of money. Fisher's theory is expanded to include both internal and external monetary sectors to be considered simultaneously. A framework for studying the relationship between interest and exchange rate is offered by relating export, import and capital account, net domestic and foreign assets of banking system in a generalized framework of quantitative theory of money and using the theories of interest rate parity and monetary approach to balance of payments. This paper concludes that there is a negative relationship between interest rate and exchange rate, ceteris paribus. A significant contribution in this paper is the adaptation of transaction value to aggregate supply concepts using United Nations System of National Accounts (1993). This clarification actually removes the vogues of critical issues of the transaction value in macroeconomic analysis. The proposed theoretical framework is tested for Iran's data. It is concluded that there is a negative relationship between exchange rate and interest rate again.

The present article assesses the existence of synchronization among the OPEC members’ business cycles. For the purposes of assessing system of simultaneous equations a "central model” due to Helbling and Brodo in the study of synchronization of business cycles, have been used. This way Synchronization between business cycles of OPEC member countries by means of synchronization between their business cycles with core country (that in this study for key role of this country in OPEC as the largest oil producer and exporter, is Saudi Arabia) is assessed. By making use of measure of residuals (which are representation of nonsynchronization) and classifying of the countries into homogenous groups by using taxonomy method, synchronization between business cycles of OPEC member countries were assessed. For being accurate on the subject, results have been controlled by stepwise regressions method with consideration of trade variable. For filtering effect of quality transitions of two countries, Kuwait and Indonesia in 1990 and 1998, these tests are accomplished without/with dummy variables. Results indicated strong synchronization between the OPEC members’ business cycles. Therefore due to effect of external dummy variables, this article concludes that their business cycles are synchronous, if OPEC member countries can protect them against external shocks and the precondition of common economic coordination (i. e., synchronization of business cycles) between them will be accomplished.

In this paper, we are going to consider assets and liabilities management (ALM) structure and instrument in Islamic banking. Since in Islamic banking depositors take partnership in benefits of bank, Islamic banking follows to maximizing benefits of beneficiaries such as depositors. Therefore, there are dissimilarities between ALM approaches in Islamic banking and conventional banking. First, this dissimilarity comes from differences on accounting system in Islamic banking in comparison to conventional banking. Secondly, usury illegalness and its related jurisprudence specifications indicate that time is not a sole effective factor on increasing equity (deposited capital) return. Therefore, profit and loss sharing resulted from investment in real economy sector is the essential base in monetary transactions in this system. These two important factors are significant factors in the Islamic ALM structure. In this paper we consider the influences of these factors in two banking approaches for creating economic value added (EVA). Comparison of financial indices for the two type of banking, the results lead us to conclude that Islamic banking is more efficient than conventional banking.

This study recognizes and analyzes the basic main factors influencing demand and supply of petroleum; also in addition, with the use of analysis of supply surplus impact on global petroleum market, designs a model for simulation and prediction of oil price. In this model, through the use of modification method of Dynamic Disequilibrium Adjustment Model (DDAM), natural gas price variables, global gross domestic product (GDP),GDP of oil producing countries, production capacity of petroleum, oil supply surplus in market and global oil price, demand and supply of petroleum are being presented. The behaviour of natural gas market are transferred meaningfully to theoil market and cause changes in oil price. In the dynamic simulations of model, the impacts of various shocks on supply and demand of oil prices are investigated and it will be predicted for the years 2008 till 2010. So, the designed model indicates that is has proved to have the ability to analyze political shocks and to predict oil prices and can be used in policy making and oil price prediction too. As a result, the model prediction shows that in the years 2008-2010 the oil price will partly go downward, frontier 100$, however this reduction will not reach to the price fall in the 1990 decade.

This paper introduces a new ICT master solution to improve the non-usury banking performance. It is proposed that with some ICT solutions, it is possible to fulfill worldly requirement by use of ICT systems without any incredulity. Since depositors are shareholders of Non-Usury Bank Corporation (NUBankCo), integrated information systems can provide suitable infrastructure for transactions recording and management done by all participant's chains; and the end of process the yields of investment capital of depositors that invest in real economy can be distributed by safe delivery channels such as branches, ATM, WEB, and Meaningful WEB IT (i. e. BPR, ERP, CRM, SCM, MES, MEX, HRM, and WFM) uses single and integrated data warehouses accompanying with standardization in all processes. It prepares PLS mechanism as main difference between conventional and non-usury banking and also simplifies risk management and decline operational risk in comparison with conventional non-usury banking. This paper aims to find a solution to the question: is it possible to connect depositors, bank, and investors in an integrated ICT system to bring out PLS mechanism? Accordingly, a new kind of bank named by "Non-Usury Bank Corporation (NubankCo)" is used to fulfill PLS criterion. Foundation of real non-usury banking can be based on an integrated ICT system that links depositors, NUBankCo, business partners, investors, stock exchange agencies, social security organizations, and certificate authorities (CA). Therefore, all related sectors may access the working flow of capital, ICT processes, and investment returns and this causes stability in financial markets and achieve social justice establishment.