Over the past two decades, the marketing of fish has recognized the importance of quality. Yet empirical analysis of market transactions could give us little insight into the value of different qualities of fish because market data are typically aggregated. We exploit a dataset on the auction...

In this paper we develop a count data model for consumer demand which explicitly allows for a large number of zero observations for the dependent variable, and separation of the participation versus quantity decisions. The advantages of the model over traditional censored and count demand models...