We formulate a stylized model that admits volatility ambiguity to the Lucas framework. The model specifies an economically motivated ambiguity penalty function that makes volatility ambiguity quantifiable with χ2-statistics, and allows for analytical solutions. The addition of volatility...

This paper proposes a new time-deformation model for stock returns sampled in transaction time and directed by a generalized duration process. Stochastic volatility in this model is driven by an observed duration process and a latent autoregressive process. Parameter estimation in the model is...