When does the tail wag the dog? Curvature and market making

Guillermo Angeris; Alex Evans; Tarun Chitra

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arXiv · 2012.08040

When does the tail wag the dog? Curvature and market making

Guillermo Angeris·Alex Evans·Tarun Chitra

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Abstract

Liquidity and trading activity on constant function market makers (CFMMs) such as Uniswap, Curve, and Balancer has grown significantly in the second half of 2020. Much of the growth of these protocols has been driven by incentivized pools or 'yield farming', which reward participants in crypto assets for providing liquidity to CFMMs. As a result, CFMMs and associated protocols, which were historically very small markets, now constitute the most liquid trading venues for a large number of crypto assets. But what does it mean for a CFMM to be the most liquid market? In this paper, we propose a basic definition of price sensitivity and liquidity. We show that this definition is tightly related to the curvature of a CFMM's trading function and can be used to explain a number of heuristic results. For example, we show that low-curvature markets are good for coins whose market value is approximately fixed and that high-curvature markets are better for liquidity providers when traders have an informational edge. Additionally, the results can also be used to model interacting markets and explain the rise of incentivized liquidity provision, also known as 'yield farming.'

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Guillermo Angeris, Alex Evans, Tarun Chitra. 2020-12-15. When does the tail wag the dog? Curvature and market making. https://arxiv.org/abs/2012.08040

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