Given the key role of liquidity in finance research, identifying high quality proxies based on daily (as opposed to intraday) data would permit liquidity to be studied over relatively long timeframes and across many countries. Using new measures and widely employed measures in the literature, we run horseraces of annual and monthly estimates of each measure against liquidity benchmarks. Our benchmarks are effective spread, realized spread, and price impact based on both Trade and Quote (TAQ) and Rule 605 data. We find that the new effective/realized spread measures win the majority of horseraces, while the Amihud [2002. Illiquidity and stock returns: cross-section and time-series effects. Journal of Financial Markets 5, 31–56] measure does well measuring price impact.

Chinese interbank foreign exchange trading was originally conducted through a centralized, anonymous limit order book (LOB). We determine the impact of the introduction of a parallel decentralized over-the-counter (OTC) market. We find that: (1) most trading migrated to the OTC, (2) the LOB price function is upward-sloping versus the OTC price function is downward-sloping, and (3) the LOB market has a single price function versus the OTC market has multiple price functions. Next, we develop a theoretical model of parallel markets that can simultaneously explain all of these empirical findings. We test a new model prediction and find support.