NBER Working Papers by Pengfei Wang

We construct a model to capture the Keynesian idea that production and employment decisions are based on expectations of aggregate demand driven by sentiments, and that realized demand follows from the production and employment decisions of firms. We cast the Keynesian idea into a simple model with imperfect information about aggregate demand and we characterize the rational expectations equilibria of this model. We find that the equilibrium is not unique despite the absence of any non-convexities or strategic complementarity in the model. In addition to multiple fundamental equilibria, there can be serially correlated stochastic equilibria driven by self-fulfilling consumer sentiments. Furthermore, these sentiment-driven equilibria are not based on randomizations of the fundamental equili...

We formalize the Keynesian insight that aggregate demand driven by sentiments can generate output fluctuations under rational expectations. When production decisions must be made under imperfect information about aggregate demand, optimal decisions based on sentiments can generate stochastic self-fulfillng rational expectations equilibria in standard economies without aggregate shocks, externalities, persistent informational frictions, or even any strategic complementarity. Our general equilibrium model is deliberately simple, but could serve as a benchmark for more complicated equilibrium models with additional features.

We show that self-fulfilling equilibria and indeterminacy can easily arise in a simple financial accelerator model with reasonable parameter calibrations and without increasing returns in production. A key feature for generating indeterminacy in our model is the countercyclical markup due to the procyclical loan to output ratio. We illustrate, via simulations, that our financial accelerator model can generate rich business cycle dynamics, including hump-shaped output in response to demand shocks as well as serial autocorrelation in output growth rates.

We argue that positive co-movements between land prices and business investment are a driving force behind the broad impact of land-price dynamics on the macroeconomy. We develop an economic mechanism that captures the co-movements by incorporating two key features into a DSGE model: We introduce land as a collateral asset in firms' credit constraints and we identify a shock that drives most of the observed fluctuations in land prices. Our estimates imply that these two features combine to generate an empirically important mechanism that amplifies and propagates macroeconomic fluctuations through the joint dynamics of land prices and business investment.