On a number of instances, I have hyperventilated here about the misuse of the Calvo pricing hypothesis, which is an analytically convenient but empirically wrong hypothesis that a only fixed proportion of firms can change prices in any given period, and that price changes are not history or state dependent. There is a very limited set of circumstances where this is a reasonable assumption, and the following paper is by far not in that set.
Willem Van Zandweghe and Alexander Wolman study monetary policy in a Calvo world. The only thing that is endogenous is the money supply. This implies in particular that the share of firms adjusting prices is constant no matter what the money supply or its growth rate are. One would have thought that firms, when faced with a larger money growth rate and thus inflation, would increase the frequency at which they adapt prices. Also, money velocity is assumed to be constant, while we know very well that it is not.
The worse is that the paper is trying to determine what the optimal monetary policy is, and even worse, it is trying to give quantitative answers. There is no way any of the results can be credible.