Stochastic Volatility and DSGE Models

This paper argues that a specification of stochastic volatility commonly used to analyze the Great Moderation in DSGE models may not be appropriate, because the level of a process with this specification does not have conditional or unconditional moments. This is unfortunate because agents may as a result expect productivity and hence consumption to be inifinite in all future periods. This observation is followed by three ways to overcome the problem.