Risky arbitrage and collateral policies

We construct a dynamic model economy in which investors from segmented markets have varying financial asset demands. Intermediaries make arbitrage profits by exploiting the price spreads across markets. Meanwhile, they are required to separately post collateral to support arbitrage trades. We show that with volatile asset demands, arbitrage becomes risky. With information frictions, a looser collateral policy might render the economy more vulnerable to extremely large demand shocks, while a tighter collateral constraint helps maintain the stability at the cost of market liquidity supply