James D. Dana, Jr. & Kathryn E. Spier, Bundling and Quality Assurance, 49 Rand J. Econ. 128 (2018).
Abstract: With imperfect private monitoring, a firm selling two experience goods can increase both producer and consumer surplus by bundling. Bundling constrains consumers to buy two products, making consumers better informed and ensuring that they use tougher punishment strategies. Both increased monitoring and increased punishment benefit other consumers, so bundling overcomes a free‐rider problem. The social value of bundling is even larger if consumers cannot attribute a negative signal to the specific product that generated it, or if one of the two goods is a durable and the other is a complementary nondurable. Our results are robust to mixed bundling.