We present both theory and evidence that increased competition may decrease rather than increase consumer welfare in subprime credit markets. We present a model of lending markets with imperfect competition, adverse selection and costly lender screening. In more competitive markets, lenders have...

Using a novel dataset where all traders are identifiable, we examine trading in the shares of a major company on the London Stock Exchange before 1920. Our main finding is that bid-ask spreads increased in the presence of informed trades. However, we also find that spreads narrowed during...