We model how ETFs compete and set fees. We show that ETF secondary market liquidity plays a key role in determining fees and leads to liquidity clienteles. More liquid ETFs charge higher fees in equilibrium and attract shorter horizon investors that are more sensitive to liquidity than to fees....

With the demise of traditional market makers and proliferation of trade execution algorithms that mix market and limit orders, it is no longer clear who provides liquidity in limit order book markets and what determines their liquidity provision decisions. To examine these issues, we develop and...

We examine the welfare costs of informed trade in a new sequential trade model with elastic uninformed traders. Welfare losses occur when the liquidity costs of executing a trade exceed the potential gains from the trade. With long-lived private information, more informed traders lead to better...

Despite the significant attention that market manipulation has received in recent years many aspects of it are poorly understood. This article identifies from the theoretical and empirical literature what we do and do not know about market manipulation, and suggests directions for future...