DP11469 A Dynamic Equilibrium Model of ETFs
I develop a dynamic general equilibrium model of exchange traded funds (ETFs) that accounts for the two-tier ETF market structure with both a centralized exchange (secondary market) and a creation/redemption mechanism (primary market) operating through market-making firms known as Authorized Participants (APs). The model is tractable and allows for any number of ETFs and basket securities. I show that the creation/redemption mechanism serves as a shock propagation channel through which temporary demand shocks may have long-lasting impacts on future prices. In particular, they may lead to a momentum in asset returns and a persistent ETF pricing gap. Improving liquidity in the primary market stimulates creation/redemption and therefore strengthens the shock propagation channel. As a result, it may
amplify the volatility of both the underlying assets and the ETF pricing gap. At the same time, introducing new ETFs may reduce both the volatility and co-movement in the returns and may improve the liquidity of the underlying securities.