Williams, John

"Should large-scale asset purchases be a standard tool of monetary policy at the [zero-lower bound], and, if so, how should they be implemented?" Mr. Williams asked in the paper, which he was scheduled to present and discuss Thursday at an event organized by the Hutchins Center on Fiscal and Monetary Policy at the Brookings Institution, a Washington think tank.

He said this and other questions need more study because being stuck at the so-called zero-lower bound is a serious problem that policymakers are likely to confront again.