Positive and negative externalities: An interesting situation occurs when there is a positive externality. This is interesting because economists state this is a result of market inefficiency or failure. Combine the lesson notes with some of your own research and your own experiences to describe when you were part of a transaction that resulted in a positive externality and why the transaction would be considered inefficient. To answer this question, a) describe the transaction, b) describe the positive externality, and c) state why, from an economist's viewpoint, this would be considered market inefficiency.