Portfolio Preferences, Relative Entropy, and Post-Trade Elasticity
A liquidity pool is a portfolio. Its reserve and price updates define an investment strategy: which assets it accumulates, which it releases, and the terms on which it changes its composition.
Multiswap's post-trade elasticity model expresses that strategy with one elasticity parameter, while retaining a rich accounting and safety structure. A natural extension is to give the portfolio an explicit preferred composition. The question is whether that preference can enter through a coherent valuation rule, preserve the post-trade framework, and strengthen the response to scarce inventory.
This article develops one such candidate. Its central result is an exact identity: the composition-sensitive part of portfolio valuation equals reference-priced holdings discounted by relative entropy from the preferred composition. The resulting prices favor acquiring underrepresented assets, retain exact invariance under uniform reserve scaling, and develop stronger elasticity near depletion.
