Abstract:
Literature review of business cycle in economic studies is very old. The economist’s viewpoints are focused on two directions. Recognition of effective factors، and statistical characteristics of business cycle. In this paper، the business cycle of Iran’s economy is investigated for 1959-2001. The methodology consists of four steps: the firs، to estimate the long-run trend of real GDP in linear form، the second، to measure deviation of real GDP from long-run trend، this gaps means، there are periods of recession and boom in economy، the third، to investigate that، the gaps of GDP are stochastic or there is a serial correlation model، we answered this question by Run-Test method. And the fourth، if serial correlation model is confirm how many years length of time a period of business cycle in Iran economics? We estimate by Box-Piers statistic. As a result: There are serial corelations in business cycle of Iran and the period of one cycle is a bout 11 years. In addition: oil incomes، investment، budget deficit and liquidity are the most important factors in forming business cycle of Iran’s economy. Long-run Economic policies for modified business cycles by this paper are obvious.
Machine summary:
Some economists emphasize determining the nature and origin of economic booms and busts, while others, while separating a period from the long-term trend, examine the fluctuations resulting from business cycles in terms of dimensions such as scope, extent, domain, duration, etc.
The second question is, if the above hypothesis is confirmed, can the fluctuations of real GDP around its long-term trend be analyzed in the form of an approximate pattern, and can the length of each complete business cycle in the Iranian economy be estimated?
83 The gap between real GDP and the long-term trend line indicates the occurrence of economic recession and boom, or in other words, the formation of business cycles.
(4) TRGDP- GDPr = GAP In connection with the existing fluctuations in the economy, the question arises: Is the gap between real GDP and the long-term trend line over time T merely random, or is there a serial correlation between the values of the gap confirmed?
In other words, it can be concluded that business cycles in the Iranian economy are not determined by random deviations around the long-term trend, and if production is less or more than its natural level in one year, this situation will continue for several periods.
Therefore, the designed model is defined as follows GAP =f (OIL , IPR , MP , BD) where GAP is the gap between actual GDP and the trend variable, whose values are positive or negative during the periods of business cycles.
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