Do Liquidity Proxies Based on Daily Prices and Quotes Really Measure Liquidity?

Entropy (Basel). 2020 Jul 17;22(7):783. doi: 10.3390/e22070783.

Abstract

This paper examines whether liquidity proxies based on different daily prices and quotes approximate latent liquidity. We compare percent-cost daily liquidity proxies with liquidity benchmarks as well as with realized variance estimates. Both benchmarks and volatility measures are obtained from high-frequency data. Our results show that liquidity proxies based on high-low-open-close prices are more correlated and display higher mutual information with volatility estimates than with liquidity benchmarks. The only percent-cost proxy that indicates higher dependency with liquidity benchmarks than with volatility estimates is the Closing Quoted Spread based on the last bid and ask quotes within a day. We consider different sampling frequencies for calculating realized variance and liquidity benchmarks, and find that our results are robust to it.

Keywords: correlation coefficient; liquidity benchmark; liquidity proxy; mutual information; partial determination; volatility estimate.