Competition on the London Stock Exchange
研究伦敦证券交易所订单驱动市场中竞争水平的决定因素，发现用户存在跟风行为，竞争在美国交易时段更激烈，且与买卖价差正相关，这些效应随股票流动性变化。
This paper investigates the determinants of the level of competition on the order–driven market organised by the London Stock Exchange. In contrast to previous empirical market microstructure studies, we treat the level of competition as an endogenous variable. The statistical nature of the measures of competitive activity used in this paper necessitate use of a count regression model. Using a sample 50 stocks, we find that users of the system tend to follow the lead of other users (termed the ‘herding effect’) and that competition is greater during the period when the US exchanges are open (termed the ‘US effect’). In addition, the level of competition is positively related to the bid–ask spread pertaining to a particular stock (termed the ‘spread effect’). The latter result is most likely due to traders following a strategy where trade immediacy is traded off against price advantage. Finally, we find that the magnitude of the herding effect, the spread effect, and the fit of the count regression models (termed the ‘fit effect’) vary in a predictable manner across the liquidity of stocks.