Using proprietary institutional trade data, we construct a price impact measure that represents the costs faced by institutional investors. We show that many widely used liquidity measures do not adequately capture institutional trading costs. We then find that institutional trading costs are not dramatically impacted by decimalization, casting doubt on the widely used identification strategy that employs decimalization as an exogenous shock to liquidity, particularly institutional liquidity. Indeed, we find that conclusions from prior research are significantly altered when we measure liquidity using institutional trading data.

This paper constructs and analyzes various measures of trading costs in US equity markets covering the period 1926–2015. These measures contain statistically and economically significant predictive signals for stock market returns and real economic activity. We decompose illiquidity proxies into a component capturing aggregate volatility and a residual. The predictive content of these components differs in important ways. Specifically, we find strong evidence that the component of illiquidity uncorrelated with volatility forecasts stock market returns. Both the volatility and residual components of illiquidity contain information regarding future economic activity.

Using unique data, this paper examines investment banks’ choice of peers in comparable companies analysis in mergers and acquisitions. We find strong evidence that product market space is amongst the most important factors in peer selection, but Standard Industrial Classification (SIC) codes, particularly three and four digit codes, do a poor job of categorizing related firms in this setting. Banks strategically select large, high growth peers with high valuation multiples, factors that are also positively related to premiums. Our evidence is consistent with target-firm advisors selecting peers with high valuation multiples to negotiate higher takeover prices.

We study brokerage platform outages to examine the impact of retail investors on financial markets. We contrast outages at Robinhood, which caters to inexperienced investors, with outages at traditional retail brokers. For stocks with high retail interest, we find that negative shocks to Robinhood investor participation are associated with reduced market order imbalances, increased market liquidity, and lower return volatility, whereas the opposite relations hold following outages at traditional retail brokerages. The findings suggest that herding by inexperienced investors can create inventory risks that harm liquidity in stocks with high retail interest, while other retail trading improves market quality.