送交者: xj 于 2007-04-06, 13:54:05:
回答: 这不就是 marginal decreasing uitility 吗? 由 插一腿 于 2007-04-06, 13:45:41:
There is a myth saying that poor people can get rich if they are more frugal. This study shows that poor people are frugal anyway, but they cannot become rich simply being frugal.