We discuss a class of markets for durable goods where efficiency (or approximate efficiency) is obtained despite the presence of information asymmetries. In the model, the number of times a good has changed hands (the vintage of the good) is an accurate signal of its quality, each consumer...

We propose a simple theoretical model of supervised learning that is potentially useful to interpret a number of empirical phenomena. The model captures a basic tradeoff between sheltering the child from the consequences of his mistakes, and allowing him to learn from experience. We characterize...