求翻译：Lu Ming, Chen Chong used from 1987 to 2001 at the provincial level panel data estimation results show that inter-regional population, household registration transformation, economic openness, non-nationalization and government participation in economic activities are widening the income gap between urban and rural residents of the factor.是什么意思？

待解决 悬赏分：1 - 离问题结束还有