Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
We present a model in which some goods trade in “customer markets” and advertising facilitates long‐lived relationships. We estimate the model on U.S. data and find a large congestion externality in the pricing of customer market goods. This motivates the analysis of optimal policy. Under a complete set of taxes, fiscal policy eliminates the externalities with large adjustments in tax rates on customer markets goods, while labor tax volatility remains low. Constraining the instruments to the interest rate and labor tax, the optimal labor tax displays large and procyclical fluctuations, but monetary policy is little changed compared to a model with no customer markets.