Essays on sluggishness in macroeconomics

My dissertation studies sluggishness in macroeconomics. It consists of three essays.; The first essay (Chapter 1) develops a model which can explain the hump-shaped impulse response of inflation to a monetary shock. A standard New Keynesian (NK) model is augmented to include a dynamic externality as well as sticky wages and variable capital utilization. In simulations, I assume purely forward-looking nominal rigidities in nominal prices and wages a la Calvo. Nevertheless, we can show that inflation is hump-shaped under a reasonable range of parameters. It will be also shown that, in order for inflation to be hump-shaped, sticky wages and variable capital utilization are important as well as a dynamic externality.; The second essay (Chapter 2) studies the role of the information updating scheme in the sticky information model. I compare the predictions of the sticky information model under two different information updating schemes: Mankiw and Reis' original updating scheme and an updating scheme where all firms do so deterministically. On the surface, both models are reasonable a priori. However, the sticky information model under our alternative scheme suffers from diminished persistence and a reduced hump-shape in its impulse response function for inflation. The attractive results in Mankiw and Reis critically depend on their information updating scheme.; Third essay (Chapter 3) extends the sticky information model by Mankiw and Reis. They apply the sticky information assumption to a model in which everything is originally static and the optimal choice is made in a static manner. In contrast, this essay considers a dynamic model in which the optimal choice is originally made dynamically due to adjustment costs. This essay applies the sticky information assumption to this type of dynamic model. A useful aggregation result with sticky information is shown. Using the neoclassical model of investment, fixed investment tends to have a hump-shaped response to a shock to profitability and to have additional persistence notwithstanding the model's simplicity.