ETF Competition and Market Quality
研究持有几乎相同证券组合的交易所交易基金之间的竞争，发现新基金加入会降低原有基金的流动性，且跟踪同一基准时影响更大，同时新竞争者的到来并未降低管理费。
Abstract This paper examines competition between exchange traded funds (ETFs) that hold nearly identical portfolios of securities. We provide evidence that incumbent‐fund liquidity is negatively affected when a new ETF is added to an asset class. The degradation in liquidity is even more severe whenever both funds follow the same benchmark. We also document a decline in primary‐market activity for the incumbent ETFs after the arrival of new competitors. Furthermore, increasing the number of funds in an asset class does not put downward pressure on fund management fees. Thus, the deterioration in market quality may not be offset by decreasing costs of fund ownership.