THE cheques are in the post. Last month, the US government began mailing tax rebates to over 130 million households. The payments, many worth hundreds of dollars, are designed to get consumers spending and breathe new life into the country’s stagnating economy.

But the plan is unlikely to have much impact, according to two economists. Their research suggests that people are much more likely to spend such rebates if they are divided into monthly payments rather than given as a lump sum.

To test the effectiveness of the government’s “economic stimulus payments”, Valrie Chambers and Marilyn Spencer at Texas A&M …