WASHINGTON (AP) — Defending a costly plan to revitalize the economy, Vice President Biden said Thursday the government’s sweeping stimulus effort “is in fact working” despite steady Republican criticism and public skepticism. “The recovery act has played a significant role in changing the trajectory of our economy and changing the conversation in this country,” Biden said. Nearly 200 days into the effort, Biden delivered an upbeat report card about the $787 billion rescue effort that President Obama pushed through Congress.