Market microstructure approach: A review of basic concepts and practices

Abstract

The article gives an overview of the market microstructure approach, where modern financial infrastructure (trading, clearing and settlement) has for the first time become an object of dedicated research, contrary to traditional microeconomic models dealing with abstract demand, supply etc. apart from market realities. The market microstructure approach focuses on analysis of market frictions impacting on how new equilibriums are being come upon. Market frictions exist due to fragmented market structure and information asymmetries. Respectively, the article (Part 1) compares "market microstructure" and "market structure"; reveals drivers of spatial and temporal fragmentation (including breakdown of modern trading protocols and participation models); analyzes information (self-) lear ning of market and adverse selection; makes distinctions between "market quality", "market efficiency" and "market liquidity"; and traces how the market efficiency and equilibrium concepts were evolving when market frictions drew attention. How the market microstructure approach may work is demonstrated in the course of a high-frequency trading (HFT) case study in Part 2 of the article. HFT has brought new evidence that market structure matters-both as an environment where tech innovations are only possible and as mechanisms to be adjusted to new challenges-and has outlined directions for further elaborations on basic microstructural concepts. The article associates HFT with market fragmentation, describes the impact of HFT on participation structure and market quality, summarizes predatory and similar practices of HFT and instruments to mitigate them, and clarifies the specifics of information asymmetry and adverse selection within the HFT framework.