Amirhosein Najafzadeh - PhD Student, Department of Economics, Qom Branch, Mofid University, Qom, Iran
Sayad Ziaaddin Kiaalhosseini - Assistant Professor, Department of Economics, Qom Branch, Mofid University, Qom, Iran

In this Research the empirical relationship between output growth and output growth uncertainty has been examined for the Islamic Republic of Iran by using quarterly data over the period 1960 – 2015. The econometric methodology employs GARCH models and Full Information Maximum Likelihood (FIML) method and proxies output uncertainty by the conditional variance of shocks to output growth. According to the results Keynes hypothesis is accepted, as a proof of an inverse relationship between these two variables

output variability, output growth, economic growth, Volatility, GARCH models