In September 2011, more than two years after Congress and the Obama administration had enacted the 2009 stimulus package, a poll conducted by the Washington Post and ABC News found that only 17 percent of those polled thought that the “Obama economic program” was “making the economy better.” Thirty-four percent thought it was making the economy worse, and 47 percent thought it was having no effect.

a. How can economists judge whether the stimulus program was effective? 

b. Might most people responding to the poll have believed that the stimulus package wasn’t helping the economy—even if it was? Briefly explain.